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  1. What kind of virus are herpesviruses?
    Enveloped double stranded linear DNA viruses
  2. Where do herpesviruses replicate
    Nucleus
  3. What is special about herpesviruses
    Remain latent inside body
  4. What is HSV
    Herpes Simplex Virus
  5. What family is herpes simplex virus from
    Herpesviruses
  6. What kind of virus is herpes simplex virus?
    Enveloped double stranded linear DNA virus
  7. Where does herpes simplex viruses replicate
    Nucleus
  8. What does herpes simplex DNA look like
    Double stranded linear
  9. What does herpes simplex virus look like under microscopy
    Host cells with cowdry bodies in their nuclei
  10. What are cowdry bodies
    • Big red eosinophilic intranuclear inclusion bodies that look like targets
    • Found in herpes virus infected cells
  11. What is the difference between herpesvirus inclusions and poxvirus inclusions in microscopy?
    • Cowdry bodies are intranuclear ? herpes virus
    • Cytoplasmic inclusions ? poxvirus
  12. How is herpes simplex transmitted
    • Sex
    • Saliva
    • Vertical transmission
  13. What are the TORCHeS infections?
    • Able to cross the placenta and infect the fetus in utero
    • Toxoplasma Gondi
    • Other (parvovirus B19, varicella zoster virus)
    • Rubella
    • Cytomegalovirus
    • Herpes simplex virus + Human immunodeficiency virus
    • Syphilis (Treponema pallidum)
  14. What strains of herpes simplex virus are there?
    1 and 2
  15. What is the difference between herpes simplex 1 and 2?
    • Herpes simplex 1 ? upper half of the body
    • Herpes simplex 2 ? lower half of the body
  16. What does herpes simplex 1 cause?
    • Initially presents as gingivostomatitis (aggressive and painful)
    • Later presents as recurring cold sores
    • Keratoconjunctivitis
    • Temporal lobe encephalitis
    • Herpetic whitlow
    • Erythema multiforme
  17. Who is most affected by gingivostomatitis caused by herpes simplex 1 infection
    Infants
  18. What is the clinical presentation of gingivostomatitis caused by herpes simplex 1 infection?
    Widespread inflammation of the lips and gums
  19. What are cold sores
    Herpes labialis = lip herpes caused by herpes simplex 1
  20. What is the most common viral infection of the mouth?
    Herpes labialis caused by herpes simplex 1 virus
  21. How do you examine keratoconjunctivitis?
    • Using fluorescein stained slit lamp exam of the eye
    • See serpiginous (snake like) ulcers on the cornea
  22. What is the clinical presentation of temporal lobe encephalitis caused by herpes simplex 1 virus?
    • Hemorrhage and necrosis of inferior and medial temporal lobes
    • Fever, headache, seizure, altered mental status
    • Personality changes
    • Bizarre behavior
    • Olfactory hallucinations
  23. What is the most common cause of sporadic encephalitis in the USA?
    Herpes simplex 1 virus
  24. Where does herpes simplex 1 virus remain latent
    Trigeminal ganglia
  25. What causes reactivation of herpes simplex 1 infection
    • Stress
    • Immunocompromisation
  26. What does the herpes simplex rash look like?
    • Dew drops on a rose petal appearance
    • Clear vesicles sitting on top of an erythematous base
  27. What is herpetic whitlow
    Herpes simplex infection on the finger
  28. Who is affected by herpetic whitlow
    • Dentists ? mouth --> hands
    • Genital --> hand contact too
  29. What causes herpetic whitlow
    Herpes simplex 1 and 2
  30. What causes Erythema multiforme
    Hypersensitivity reaction to different bacteria, viruses and drugs
  31. What is erythema multiforme commonly associated with
    herpes simplex 1 virus
  32. What is the clinical presentation of erythema multiforme?
    • Rash appearing 1-2 weeks after infection with herpes simplex 1 virus
    • Small target lesions usually on backs of hands and feet
  33. What does herpes simplex 2 virus infection cause?
    • Herpes genitalis
    • Aseptic meningitis in adolescents and adults
  34. What is the clinical presentation of herpes genitalis caused by herpes simplex 2?
    • Painful inguinal lymphadenopathy
    • Clusters of vesicles with red base
  35. Where does herpes simplex 2 virus remain latent
    Sacral ganglia
  36. Who is affected by aseptic meningitis caused by herpes simplex 2
    Adolescents and adults
  37. How do we diagnose herpes viruses?
    PCR
  38. How do we diagnose herpes simplex viruses?
    • PCR
    • Tzank smear
  39. How and why is Tzank smear performed
    • Diagnose herpes simplex virus infection
    • Scrape ulcer base and smear contents on slide, stain and analyze by microscopy
  40. What do you look for in a Tzank smear to diagnose herpes simplex virus infection?
    Multinucleated giant cells characteristic of herpes infection
  41. How do you treat herpes simplex virus infections?
    • No cure
    • Can prevent breakouts of vesicles though ? Acyclovir / Valcyclovir
  42. What do we use acyclovir and valcyclovir for in herpes simplex infection?
    Prevent breakouts
  43. What is VZV
    Varicella zoster virus
  44. What kind of virus is varicella zoster virus?
    Enveloped double stranded linear DNA virus
  45. What family does varicella zoster virus belong to?
    Herpesviruses
  46. What does varicella zoster virus cause?
    Chicken pox
  47. What does exanthema mean
    Widespread rash
  48. What is the clinical presentation of chicken pox caused by varicella zoster virus?
    • Exanthema = widespread itchy rash
    • Fever
    • Headache
  49. Who is most affected by chicken pox caused by varicella zoster virus
    Children
  50. How is varicella zoster virus transmitted?
    • Respiratory droplets
    • Or from the ruptured vesicles themselves
  51. What does chicken pox rash look like
    • Vesicular lesions on surrounding erythema = dewdrop on a rose
    • Lesions will be in different stages: blister --> healing scabs
  52. What causes dewdrop on a rose rash
    • Varicella zoster virus
    • Herpes simplex virus
  53. What is the difference between smallpox rash and chicken pox rash?
    • Smallpox rash ? smallpox virus ? rash has lesions all at the same stage
    • Chicken pox rash ? varicella zoster virus ? rash has lesions in many different stages
  54. How can we diagnose varicella zoster virus infection?
    Tzank smear shows multinucleated giant cells
  55. What can we use the Tzank smear to diagnose?
    • Varicella zoster virus infection
    • Herpes simplex virus infection
  56. Who is affected by complications of chicken pox caused by varicella zoster virus
    adults who are immunocompromised
  57. What are the possible complications of chicken pox caused by varicella zoster virus?
    • Pneumonia
    • Encephalitis
  58. What is a major cause of morbidity and mortality in adults with chicken pox caused by varicella zoster virus?
    Pneumonia
  59. How do we treat chicken pox caused by varicella zoster virus infection?
    • Acyclovir ? used in people over age of 12 and immunocompromised individuals
    • Vaccine
  60. What kind of vaccine is the chicken pox vaccine for varicella zoster virus?
    Live attenuated vaccine
  61. Who do we treat for varicella zoster virus infections?
    • People over 12
    • Immunocompromised
  62. Where does varicella zoster virus remain latent
    Dorsal root ganglia
  63. When does varicella zoster virus reactivate
    • Stress ? emotional too
    • Immunocompromised
    • Elderly
  64. What do we call reactivation of varicella zoster virus?
    • Herpes zoster
    • Shingles
  65. What is shingles
    • Reactivated varicella zoster virus
    • Extremely painful chick pox like rash
  66. What does shingles caused by reactivated varicella zoster virus look like
    • Dewdrop on a rose appearance of vesicles on erythematous base
    • Dermatomal distribution of rash
  67. Why is shingles seen in dermatomal distribution?
    • When varicella zoster virus reactivates it travels down from dorsal root ganglion through sensory nerve fibers until it reaches the skin
    • What is disseminated varicella zoster virus
    • Shingles that crosses the midline and affects more than one dermatome
    • Red flag that someone is immunocompromised
  68. What should you do if you see someone with disseminated varicella zoster virus
    • Ask about chemotherapy or other immunosuppression therapies
    • Test for HIV
  69. What is post herpetic neuralgia
    Pain that is felt in the dermatome affected by shingles after reactivation of varicella zoster virus even after the rash has gone away
  70. Which dermatomes are most affected by reactivation of varicella zoster virus
    • Thoracic dermatomes
    • Occasionally trigeminal nerve ? in immunocompromised people
  71. What is herpes zoster opthalmicus?
    • Loss of vision caused by reactivation of herpes zoster virus in the trigeminal nerve
    • Usually only one eye is affected
    • Often in immunocompromised hosts
  72. Who is affected by herpes zoster opthalmicus
    Immunocompromised hosts
  73. How do we treat shingles caused by herpes zoster virus reactivation?
    • Acyclovir
    • Famciclovir ? easier dosing
    • Valacyclovir
    • Zoster vaccine ? adults > 60
  74. Who should get the zoster vaccine
    Adults over 60
  75. What kind of vaccine is the zoster vaccine?
    Live attenuated vaccine
  76. Who cannot receive the varicella zoster vaccines (chicken pox and zoster) and why
    • Immunocompromised people because they are live attenuated so could overwhelm immune system
    • Pregnant women
    • People with leukemia / lymphoma
    • HIV patients with CD4 count <200
  77. What are the TORCHeS infections?
    • Infections that can pass through the placenta to the fetus in utero
    • Toxoplasma Gondi
    • Other (varicella zoster virus, parvovirus B19)
    • Rubella
    • Cytomegalovirus
    • Herpes simplex virus + Human immunodeficiency virus
    • Syphilis (Treponema pallidum)
  78. When is the highest risk moment during pregnancy to get varicella zoster virus infection?
    First 2 trimesters
  79. What does congenital varicella syndrome cause?
    • Limb hypoplasia
    • Cutaneous scarring in dermatomal pattern
    • Blindness
  80. What is EBV
    Epstein Barr Virus
  81. What family is Epstein Barr virus from
    Herpes viruses
  82. What kind of virus is Epstein Barr virus?
    Enveloped linear double stranded DNA virus
  83. What does Epstein Barr virus cause?
    • Infectious mononucleosis
    • Associated with some cancers
    • Oral harry leukoplakia
  84. What is the clinical presentation of infectious mononucleosis caused by Epstein Barr virus?
    • Pharyngitis with difficulty swallowing due to pain
    • Fever
    • Tender lymphadenopathy usually in posterior cervical region but could be generalized
    • Splenomegaly
  85. How is Epstein Barr virus transmitted?
    Saliva when sharing drink or kiss
  86. What distinguishes Epstein Barr virus from other causes of pharyngitis
    Generalized lymphadenopathy can occur in mononucleosis (Epstein Barr virus)
  87. Which T cells are CD8+
    Cytotoxic T cells
  88. What does mononucleosis caused by Epstein Barr virus look like under microscope
    • Reactive lymphocytosis on blood smear
    • Downy cells = atypical cells = reactive lymphocytes
  89. What are Downey cells and where do we find them?
    • Blood smear of patient infected with Epstein Barr virus (plus some other situations)
    • Reactive cytotoxic T lymphocytes or natural killer cells
  90. What do Downey cells look like?
    • Very large with lots of cytoplasm
    • Oval or indented or folded nucleus
  91. Why do we have lymphadenopathy and splenomegaly in mononucleosis caused by Epstein Barr virus
    Lymphocytes (cytotoxic T cells and natural killer cells) proliferate
  92. What is the pathogenesis of Epstein Barr virus?
    • Encounters new host
    • Epstein Barr virus envelope glycoprotein binds to CD21 in B cells
  93. What does Epstein Barr virus target?
    • B lymphocytes
    • CD21 receptors
  94. What is the role of B lymphocytes in the body?
    • Turn into plasma cells --> make antibodies
    • Remain dormant as memory cells
  95. Where does Epstein Barr virus remain latent
    In B cells
  96. What is CD21
    Receptor for compliment C3D
  97. What is the marker for B cells?
    CD21
  98. How do you distinguish strep throat from mono?
    • Strep throat ? streptococcus pyogenes ? seen in children and adolescents
    • Mono = Epstein Barr virus ? usually asymptomatic in young age
  99. What happens if you mistreat mononucleosis caused by Epstein Barr virus with ampicillin or amoxicillin
    • Might think it is strep throat --> use antibiotics
    • Maculopapular rash
  100. What cancers is Epstein Barr virus associated with
    • Mixed cellularity Hodgkin?s B cell lymphoma
    • Burkitt lymphoma
    • Nasopharyngeal carcinoma
  101. Who is at high risk of developing B cell lymphoma when infected with Epstein Barr virus
    Patients with weakened immune systems
  102. What types of B cell lymphoma are there?
    • Hodgkin?s lymphoma
    • Non-hodgkin?s lymphoma
  103. What is Hodgkin?s lymphoma characterized by?
    Reed Sternberg cells = owl eye cells
  104. What type of B cell lymphoma is Epstein Barr virus associated with?
    • Mixed cellularity Hodgkin?s lymphoma
    • Burkitt lymphoma
  105. What non-Hodgkin?s lymphoma is associated with Epstein Barr virus?
    Burkitt lymphoma
  106. What is the clinical presentation of endemic / African Burkitt lymphoma?
    Large lesion in the jaw with swelling
  107. What is the clinical presentation of non-endemic / sporadic Burkitt lymphoma?
    Ileocecal / peritoneum lesion
  108. Who is most affected by nasopharyngeal carcinoma
    Asians
  109. What is oral harry leukoplakia caused by Epstein Barr virus
    • NOT precancerous lesion and does not develop into squamous cell carcinoma
    • Lesions that appear on lateral portion of tongue
  110. Who is most affected by oral harry leukoplakia caused by Epstein Barr virus
    HIV patients
  111. How do you differentiate oral thrush and oral harry leukoplakia?
    • Oral thrush ? candida ? can scrape it off the tongue
    • Oral harry leukoplakia ? Epstein Barr virus ? cannot be scraped off the tongue
  112. How do we diagnose Epstein Barr virus infection?
    Mono spot test
  113. How does the Epstein Barr virus mono spot test work?
    • In acute infection Epstein Barr virus activated B cells to secrete heterophile anti-sheep red blood cell antibodies
    • Mix patient?s serum (with antibodies) with sheep or horse red blood cells --> agglutination
  114. How do you treat mononucleosis caused by Epstein Barr virus?
    Supportive therapy
  115. Why must patients who have had mononucleosis caused by Epstein Barr virus avoid contact sports
    Increased risk of splenic rupture due to splenomegaly
  116. How common is splenomegaly in patients infected with Epstein Barr virus?
    50-60% patients with mono
  117. what kind of virus is cytomegalovirus?
    enveloped double stranded linear DNA virus
  118. what family is cytomegalovirus part of
    herpesviruses
  119. what is CMV
    cytomegalovirus
  120. where does cytomegalovirus replicate
    inside the nucleus
  121. where does cytomegalovirus remain latent
    mononuclear leukocytes
  122. what are mononuclear cells
    • white blood cells with one nucleus
    • lymphocytes
    • monocytes
    • macrophages
  123. when does cytomegalovirus become reactivated
    when person becomes immunosuppressed
  124. how is cytomegalovirus transmitted
    • blood
    • sexually contact
    • breast milk
    • saliva
    • urine
  125. what are the TORCHeS infections?
    • infections that can pass through the placenta and infect fetus in utero
    • Toxoplasma Gondi
    • Other (varicella zoster, parvovirus B19)
    • Rubella
    • Cytomegalovirus
    • Herpes simplex virus + Human immunodeficiency virus
    • Syphilis (Treponema pallidum)
  126. What is the most common fetal viral infection?
    Congenital cytomegalovirus infection
  127. What is the clinical presentation of congenital cytomegalovirus infection?
    • Usually asymptomatic
    • Blueberry muffin rash due to thrombocytopenia --> petechial rash
    • Hepatosplenomegaly and jaundice
    • Sensorineural hearing loss
    • Structural abnormalities in the brain --> mental retardation / seizures
  128. What structural brain abnormalities can congenital cytomegalovirus cause?
    intracranial calcifications and ventriculomegaly
  129. What causes blueberry muffin rash
    • Thrombocytopenia --> petechial rash
    • Congenital Cytomegalovirus
    • Congenital Rubella
  130. Where do intracranial calcifications caused by congenital cytomegalovirus infection
    • Periventricularly
    • Parenchyma
  131. What congenital infections cause intracranial calcifications?
    • Congenital cytomegalovirus infection
    • Toxoplasma Gondi
  132. How often is congenital cytomegalovirus infection symptomatic
    • 10-20%
    • 15% develop unilateral progressive hearing loss
  133. Which trimester is associated with the highest risk of developing congenital cytomegalovirus infection
    2nd trimester
  134. What is hydrops fetalis
    • Heart failure in utero leading to sever edema with fluid accumulation in multiple compartments
    • Usually leads to spontaneous abortion
  135. What is the number one cause of mental retardation from a congenital viral infection?
    Cytomegalovirus
  136. What is the number one cause of sensoneural hearing loss?
    Cytomegalovirus
  137. What does cytomegalovirus infection cause?
    • Congenital cytomegalovirus
    • Pneumonia
    • Retinitis
    • Esophagitis
    • Colitis
    • Mononucleosis
  138. Who is most affected by cytomegalovirus infections
    • Immunosuppressed people
    • Transplant patients on immunosuppressant
    • HIV AIDS ? especially when CD4 count drops <50
  139. Who is most affected by cytomegalovirus pneumonia
    Transplant patients
  140. How can you detect cytomegalovirus in transplant patients?
    Buffy coat culture
  141. What is the buffy coat?
    Part of the blood that contains white blood cells and platelets
  142. What is a buffy coat culture and what is it used for?
    • Culturing cytomegalovirus
    • Incubated white blood cells and platelets (buffy coat cells) with fluorescent anti-CMV antibodies and detect presence of virus
  143. Who is most affected by cytomegalovirus retinitis
    HIV AIDs patients when CD4 count drops below 50
  144. What is cytomegalovirus retinitis
    • Full thickness retinal necrosis
    • Pizza pie retinopathy
  145. What is the clinical presentation of cytomegalovirus retinitis?
    • Blind sport
    • Flashing lights
    • Vision loss
    • Typically, unilateral
  146. What cytomegalovirus infections can HIV AIDs patients have
    • Retinitis
    • Esophagitis
    • Colitis
  147. What is the clinical presentation of cytomegalovirus esophagitis?
    Singular deep linear ulcerations in the esophagus
  148. What is the difference between cytomegalovirus esophagitis and herpes esophagitis?
    • Cytomegalovirus esophagitis has singular deep linear ulcers
    • Herpes esophagitis is usually multiple
  149. What is the clinical presentation of cytomegalovirus colitis?
    Ulcerations in colonic walls
  150. What does cytomegalovirus look like under the microscope?
    Owl eye inclusions in cells it has infected
  151. How do we treat cytomegalovirus infection?
    • Ganciclovir
    • Foscarnet ? when resistant
  152. How does cytomegalovirus become resistant to ganciclovir?
    UL97 gene mutation
  153. What do we use to treat resistant cytomegalovirus infections?
    Foscarnet
  154. What do non immunosuppressed patients develop when infected with cytomegalovirus
    CMV mononucleosis
  155. What is the clinical presentation of CMV mononucleosis?
    • Same symptoms as EBV mononucleosis
    • Generalized adenopathy
    • Sever painful sore throat
    • Fatigue
  156. How do you tell the difference between cytomegalovirus mono and Epstein Barr virus mono?
    • Mono spot test on pharyngeal swab is positive ? Epstein Barr virus
    • Mono spot test on pharyngeal swab is negative ? CMV
  157. What is HHV6
    Human Herpes Virus 6
  158. What kind of virus is human herpes virus 6?
    Enveloped double stranded linear DNA virus
  159. What family is human herpes virus 6 part of
    Herpesviruses
  160. What does human herpes virus 6 cause?
    • Roseola
    • Immunosuppression
  161. What are herpesviruses primary hosts
    Humans
  162. What is sixth disease
    Roseola caused by human herpes virus 6
  163. What kind of cells does human herpes virus 6 infect?
    CD4 helper T cells
  164. How can human herpes virus 6 infection cause immunosuppression?
    Infects CD4+ helper T cells and kills off this population
  165. What is exanthema subitum
    Roseola / sixth disease caused by human herpes virus 6
  166. What is the clinical presentation of roseola caused by human herpes virus 6?
    • Exanthema subitum
    • High fever (40oC) lasting 3-4 days --> seizures
    • Followed by diffuse macular rash ? lacy appearance that spares the face
  167. Who is most affected by roseola caused by human herpes virus 6 infection
    Children between 6 months-2 years old
  168. How long does fever last in roseola caused by human herpes virus 6
    3-4 days
  169. What causes seizures in roseola caused by human herpes virus 6
    Very high fever = febrile seizures
  170. What does roseola caused by human herpes virus 6 rash look like
    Lacy appearance that spares the face
  171. How do you differentiate roseola caused by HHV6 from other childhood viral rash producing illnesses?
    • Timing of fever in relationship to rash ? fever for 4 days and THEN rash appears
    • Very high fever lasts 4 days ? over 40oC ? can cause febrile seizures
  172. How do you differentiate between roseola and measles?
    • Roseola (HHV6) ? fever lasts 4 days THEN get rash that spares the face
    • Measles ? fever and rash occur together and rash does NOT spare face
  173. How do we treat human herpes virus 6 infection?
    Supportive treatment ? cooling and fluid replacement
  174. What kind of viruses are orthomyxoviruses?
    Enveloped negative sense RNA viruses
  175. What do the orthomyxoviruses cause
    Influenza
  176. Where do orthomyxoviruses replicate
    Nucleus
  177. What viruses are in the orthomyxovirus family
    Influenza virus
  178. What family does influenza virus belong to?
    Orthomyxoviruses
  179. What kind of virus is influenza virus?
    Enveloped negative sense RNA virus
  180. How many strains of influenza virus are there?
    A, B and C
  181. Where does influenza replicate
    In the nucleus
  182. How many segments of RNA are in orthomyxoviruses?
    8 segments of negative sense RNA
  183. Which viruses are segmented
    • BOAR
    • Bunyavirus
    • Orthomyxovirus
    • Arenavirus
    • Reovirus
  184. How can orthomyxoviruses mutate
    • Antigenic shift
    • Antigenic drift
  185. What is antigenic drift
    Point mutations in the viral genome leading to changes in the hemagglutinin or neuraminidase molecules
  186. What is antigenic shift
    • Occur when antigenic segments of RNA are shared between different species
    • hemagglutinins and neuraminidases can combine to form new virus that is a mixture of the surface antigens
  187. Why do we need a new flu shot every year?
    Antigenic drift point mutations slightly alter the influenza virus
  188. What is associated with epidemics
    Antigenic drift
  189. What is an epidemic
    • Disease outbreaks limited to one particular geographic area
    • e.g. seasonal flu outbreak
  190. What is associated with pandemics
    Antigenic shifts
  191. What is a pandemic
    Outbreak of a disease that occurs over multiple continents or world wide
  192. How do orthomyxoviruses exhibit antigenic variation?
    Through antigenic drifts and shift in their hemagglutinin and neuraminidase
  193. What and when was the swine flu pandemic
    H1N1 outbreak in 2009
  194. What is H1N1
    • Swine flu
    • Result of antigenic shift between human, avian, and swine influenza virus
  195. What does influenza A cause
    Epidemics and pandemic
  196. What does influenza B
    Endemic
  197. Which strain of influenza is associated with epidemic shifts
    Influenza A
  198. What are the important virulence factors of influenza virus?
    • hemagglutinin
    • neuraminidase
    • M2 protein
  199. What is HA
    • hemagglutinin
    • glycoprotein on the surface of influenza viruses
    • binds to sialic acid found on cell membranes in the upper respiratory tract and red blood cells
  200. where can we find sialic acid
    • in membranes of cells in upper respiratory tract
    • red blood cells
  201. what influenza virulence factor causes red blood cells to clump together in test tubes
    hemagglutinin
  202. what HA antigens are seen in influenza viruses that infect humans
    H1 H2 H3
  203. What does hemagglutinin do
    • Binds to sialic acid in membranes of upper respiratory cells and red blood cells
    • Determines which cells the influenza virus can bind to
  204. Why do certain strains of the flu not infect humans?
    The hemagglutinin is not able to bind to human cells
  205. What is the tropism
    The cells that a virus can infect
  206. What protects you from getting infected with the same strain of influenza twice
    Anti-HA antibodies
  207. How does influenza virus cause infection?
    • hemagglutinin on virus binds to sialic acid on the cell membrane
    • virus is endocytosed into cell
    • viral uncoating
    • replication inside the nucleus
    • viruses become bound to host cell after replication through hemagglutinin and sialic acid interactions as before
  208. what conditions must be present for influenza viral uncoating to occur
    pH must be just right
  209. what is the M2 protein of influenza virus
    proton channel
  210. what is the function of M2 protein in influenza virus?
    creates the ideal pH for viral uncoating
  211. how do amantadine and rimantadine work
    inhibit M2 protein to prevent viral uncoating
  212. how do you treat influenza infections?
    • amantadine / rimantadine ? block M2 protein
    • oseltamivir / anamivir (tami flu) ? inhibit neuraminidase
    • vaccine
  213. why don?t we use amantadine or rimantadine anymore?
    • high level of resistance that exists in current influenza viral strains
    • only work against influenza A because influenza B does not have an M2 protein
  214. why do we only use amantadine and rimantadine in treatment of influenza virus A
    influenza virus B does not have an M2 protein
  215. what else do we amantadine for
    • treatment of Parkinson?s disease
    • increases dopamine release in the CNS through an unknown mechanism
  216. what is NA
    neuraminidase
  217. what is the function of neuraminidase?
    cleaves sialic acid to release the newly formed virions from host cell
  218. how do oseltamivir and anamivir (tami flu) work
    • inhibit neuraminidase
    • prevent the release of newly formed virions
  219. when do we give oseltamivir and anamivir (tami flu)?
    first 72 hours of infection ? before virions are replicated and released
  220. how is influenza virus transmitted?
    respiratory droplets
  221. when is the ?flu season?
    December to February
  222. When do we give influenza vaccine?
    • Around October ? before flu season
    • After 6 months
  223. What kind of vaccine is influenza vaccine?
    • Live attenuated nasal spray
    • Killed injectable form
  224. What forms of killed injectable vaccine for influenza vaccine are available
    • Trivalent ? 2 A strains and 1 B strain
    • Quadrivalent ? 2 A strains and 2 B strain
  225. What is in the trivalent vaccine for influenza
    • 2A
    • 1B
  226. What is in the quadrivalent vaccine for influenza
    • 2A
    • 2B
  227. What is the clinical presentation of influenza?
    • Myalgia ? muscle pain
    • Fever
    • Nonproductive cough for about 7 days
  228. What is a major complication of influenza?
    • Pneumonia caused by staph aureus (or strep pneumo etc.)
    • Reye syndrome
  229. What is a common cause of bacterial superinfection in influenza?
    Staphylococcus aureus
  230. Why don?t we give children with influenza infection aspirin?
    Risk of developing Reye syndrome
  231. What is the clinical presentation of Reye syndrome?
    • Fatty liver and Liver failure
    • Encephalitis
    • Fever
    • Rash
    • Vomiting
  232. What causes Reye syndrome
    Aspirin uncouples oxidative phosphorylation in hepatic mitochondria
  233. What are uncoupling agents
    Things that disrupt the proton gradient along the electron transport chain
  234. What can you see in microscopic analysis in Reye syndrome?
    Extensive damage to hepatic mitochondria
  235. How do you prevent Reye syndrome?
    Avoid aspirin in children and teenagers who have a viral infection or are recovering from one
  236. What is guillain-barr? syndrome
    Ascending paralysis starting in the feet and moving upwards
  237. What causes guillain-barr? syndrome
    • Campylobacter
    • Influenza virus
  238. What do you find in the CSF in guillain-barr? syndrome?
    • High protein with low white blood cell counts
    • Albumino cytologic dissociation

    • What kind of viruses are togaviruses?
    • Enveloped positive sense RNA virus
  239. where do togaviruses replicate
    in the cytoplasm
  240. which viruses are in the togavirus family
    • arbovirus
    • rubella
  241. how are togaviruses replicated
    • using host RNA polymerase produce one long polyprotein precursor
    • polyprotein is cleaved by viral and host proteases
  242. What kind of virus is rubella virus?
    Enveloped positive sense RNA virus
  243. What family does rubella virus belong to?
    Togaviruses
  244. What is another name for rubella?
    German measles
  245. Who is most affected by rubella virus
    Children
  246. What does rubella virus cause?
    • Rubella = German measles
    • Congenital rubella
    • Rubella in childhood
    • Rubella in adulthood
  247. What is the clinical presentation of rubella in childhood?
    • Exanthema = maculopapular rash that begins on the face and spread downward and is present for 3 days
    • Tender post auricular and occipital lymphadenopathy
    • Mild fever and fatigue
  248. How do you tell the difference between rubella and measles just by clinical presentation?
    • Rash of rubella moves faster than the rash of measles
    • Rash of rubella does not darken or coalesce
  249. How long does rash of rubella last?
    3 days
  250. How is rubella transmitted
    Respiratory droplets
  251. What is the clinical presentation of congenital rubella?
    • Mental retardation
    • Microcephaly
    • Deafness
    • Blindness
    • Cataracts
    • Jaundice
    • Patent ductus arteriosus
    • Pulmonic stenosis
    • Purpuric blueberry muffin rash
    • Radiolucent bone lesions
  252. What pathogens cause the TORCHeS infections
    • T ? Toxoplasma Gondi
    • O ? Other (varicella zoster virus + parvovirus B19)
    • R ? Rubella
    • C ? Cytomegalovirus (CMV)
    • H ? Human Immunodeficiency Virus (HIV) + Herpes Simplex Virus (HSV)
    • S ? Syphilis
  253. What are the TORCHeS infections?
    Able to cross placenta and infect fetus in utero
  254. What do TORCHeS infections cause
    Congenital infections
  255. What is the main triad of symptoms for congenital rubella?
    • Congenital cataracts
    • Sensory neural deafness
    • Patent ductus arteriosus
  256. What is the clinical presentation of rubella in the adult?
    • Lymphadenopathy and fever
    • Arthralgia = pain in joints
    • Arthritis
  257. What is the treatment for rubella?
    • No treatment
    • MMR Vaccine
  258. What organisms are covered in the MMR vaccine
    • Measles
    • Mumps
    • Rubella
  259. What kind of vaccine is the MMR?
    • Live attenuated vaccine
    • Induces both humoral and cell mediated immunity
  260. Who should be vaccinated with MMR vaccine
    • Anyone
    • EXCEPT pregnant women and immunocompromised people (live vaccine)
  261. How long should women wait to get pregnant after getting MMR vaccine and why
    1 month reduce risk of transmission of the live organisms to fetus
  262. When can we vaccinate HIV patients with MMR
    Should wait until CD4 cell count is high enough (>200)
  263. Who is most affected by rubella virus
    • Immigrants who are not vaccinated
    • Antivaccers who believe MMR is linked to autism
  264. What kind of virus is parvovirus B19?
    Naked single stranded DNA virus
  265. What does parvovirus B19 cause
    • Slapped cheek disease in children = fifths disease = erythema infectiosum
    • Arthritis in adults
    • Transient aplastic anemia
  266. What is special about parvovirus B19
    • Smallest DNA virus
    • Single stranded DNA
  267. How is parvovirus B19 transmitted
    • Respiratory droplets
    • Vertical transmission from mother to baby
  268. What are the TORCHeS infections?
    • Infections that can pass through the placenta to the fetus in utero
    • Toxoplasma Gondi
    • Other (varicella zoster virus + Parvovirus B19)
    • Rubella
    • Cytomegalovirus
    • Herpes simplex virus + Human immunodeficiency virus
    • Syphilis (Treponema pallidum)
  269. What is fifth disease
    Erythema infectiosum = slapped cheek disease
  270. What is the clinical presentation of slapped cheek disease caused by parvovirus B19?
    • Low grade fever which lasts a week
    • Once the fever breaks a slapped cheek rash appears
    • This progresses to lacy reticular pattern that travels down the body
  271. How do you differentiate between fifth and sixth disease?
    • Fifth disease = slapped cheek disease (parvovirus B19) ? low grade fever for a week
    • Sixth disease = roseola (human herpes virus 6) ? high grade fever responsible for seizures
  272. What is the clinical presentation of adult infection with parvovirus B19?
    • Joint pain
    • Arthritis
    • Edema
  273. Who is at risk of infection caused by parvovirus B19
    • Children ? slapped cheek disease
    • School teachers ? arthritis
  274. Who is at risk of developing transient aplastic anemia when infected with parvovirus B19
    People with sickle cell disease
  275. How is transient aplastic anemia caused by parvovirus B19
    • Depletion of the bone marrow
    • Fades once virus clears out
  276. What does depletion of the bone marrow look like
    • Only adipocytes left as all other cell lines are depleted
    • Cobweb look
  277. How long does aplastic anemia caused by parvovirus B19 last
    Only as long as the virus is present
  278. What does congenital parvovirus B19 infection cause?
    Hydrops fetalis --> congenital heart failure --> death
  279. When is the highest risk trimester of pregnancy to get parvovirus B19 infection?
    First 2 trimesters ? hydrops fetalis
  280. What is hydrops fetalis caused by parvovirus B19
    • Severe fetal anemia leading to extremely sever fetal version of Congestive heart failure
    • Massive edema will eventually lead to fetal demise
  281. What can cause hydrops fetalis
    • Alpha thalassemia ? fetus only makes hemoglobin Bart?s
    • Congenital parvovirus B19 infection
  282. What kind of viruses are adenoviruses?
    Naked DNA virus
  283. Where do adenoviruses replicate
    In the nucleus
  284. What is the most common cause of infection of the adenoids and tonsils?
    Adenovirus
  285. What do adenoviruses cause
    • Tonsillitis
    • Hemorrhagic cystitis
    • Pink eye
  286. How is adenovirus transmitted
    • Respiratory droplets
    • Fecal oral route
  287. Who is most affected by adenoviruses
    • Little children ? don?t wash hands etc.
    • Military recruits ? close quarters
    • Public pools ? fecal oral
  288. What is hemorrhagic cystitis
    Bladder infection that leads to gross hematuria
  289. What is pink eye
    Viral conjunctivitis commonly caused by adenoviruses
  290. How do we treat adenovirus infection?
    Vaccine
  291. What kind of vaccine is the adenovirus vaccine?
    Live attenuated vaccine
  292. Who should be vaccinated against adenovirus
    Military recruits
  293. What kind of virus is Calicivirus?
    Naked positive sense RNA virus
  294. How do caliciviruses replicate
    • Uses host cells RNA polymerase to create one long polyprotein chain
    • This is processed and cleaved by viral proteases into smaller active constituents
  295. Where do caliciviruses replicate
    In the cytoplasm
  296. What viruses are in the calicivirus family
    Norovirus = Norwalk virus
  297. What is the most common type of calicivirus seen clinically?
    Norovirus = Norwalk virus
  298. Who is affected by norovirus
    • Anyone who lives in close quarters
    • Cruises
    • Children in daycare facilities / schools
  299. What is responsible for over 90% of diarrheal outbreaks on cruises
    Norovirus
  300. How is norovirus commonly transmitted
    • Close contact
    • Shellfish ? oysters
    • other foods that are handled and served raw (e.g. buffet)
  301. what does norovirus cause
    explosive viral gastroenteritis with watery diarrhea
  302. What kind of virus is poliovirus?
    Naked positive sense RNA virus
  303. What family is poliovirus from
    Picornaviruses
  304. What does poliovirus cause
    • Polio
    • Aseptic meningitis
  305. Where can we find polio
    • Diseases has been largely eradicated in most of the world
    • Some parts of Asia and Africa
  306. How have we reduced the incidence of polio throughout the world
    Vaccination efforts
  307. How is polio transmitted
    Fecal oral route
  308. What biochemical properties does poliovirus have?
    Acid stable
  309. What must viruses passed by fecal oral route be
    Acid stable
  310. Where does poliovirus replicate
    • Enters GI tract
    • Initially starts replicating in lymphoid tissue of tonsils / peyers patches
  311. What are peyers patches
    • Collection of lymphoid tissue similar to the tonsils
    • Located in submucosa of ilium
  312. How long does it take for poliovirus to replicate?
    2-3 weeks
  313. Where is the area where poliovirus causes the most damage?
    Anterior horn of lower motor neuron cell bodies
  314. What is the clinical presentation of polio?
    • Asymmetric ascending paralysis concentrated in lower legs 2-3 weeks following infection
    • Myalgia = muscle pain
    • Decreased deep tendon reflexes
    • Eventually respiratory insufficiency from the paralysis of the diaphragm
  315. What kind of paralysis does poliovirus cause?
    Asymmetric ascending paralysis
  316. Where is poliovirus paralysis most concentrated
    Lower legs
  317. What is the main cause of death in polio?
    Respiratory insufficiency when diaphragm gets paralyzed
  318. What is the number one cause of viral meningitis?
    Enteroviruses
  319. What is the treatment for poliovirus?
    • There is none
    • Prevention through vaccination
  320. What kind of vaccine is the polio vaccine?
    • Salk vaccine ? inactivated killed vaccine ? injection
    • Sabin vaccine ? live attenuated vaccine ? oral
  321. What kind of vaccine is the Salk polio vaccine?
    Inactivated killed vaccine
  322. How do we administer Salk polio vaccine?
    Parenteral injection
  323. What kind of vaccine is the Sabin polio vaccine?
    Live attenuated vaccine
  324. How do we administer Sabin polio vaccine?
    Orally
  325. What are the disadvantages to Salk polio vaccine?
    • Killed vaccine administered by injection
    • Bypasses gastrointestinal tract
    • Only IgG forms NO IgA antibodies
  326. What is the primary immunity in mucosal surfaces?
    IgA
  327. What are the disadvantages to the Sabin polio vaccine?
    • Live attenuated vaccine given orally
    • Can be shed in feces and possibly revert to a form that can cause paralysis in another person
  328. Why does the USA use the Salt polio vaccine?
    Killed vaccine has no risk of reverting and causing infection in another person after passage in feces
  329. What kind of immunity does the Salk polio vaccine create?
    • IgG only
    • Bypasses the gastrointestinal tract so can?t form IgA
  330. What kind of immunity does the Sabin polio vaccine create?
    • IgG and IgA
    • Oral administration means it goes through gastrointestinal tract and is targeted by IgA
  331. Which viruses are part of the enterovirus group
    • Poliovirus
    • Coxsakie A and B
    • Echovirus
  332. What family are Coxsakie viruses from
    Picornaviruses
  333. Which group of picornaviruses are Coxsakie viruses from
    Enteroviruses
  334. What kind of viruses are Coxsakie viruses?
    Naked positive sense RNA viruses
  335. What kinds of coxsakie viruses are there
    A and B
  336. What does Coxsakie A infection cause
    • Hand, Foot and Mouth disease
    • Meningitis
  337. What is the clinical presentation of hand foot and mouth disease caused by Coxsakie A virus infection?
    Red vesicular rash
  338. What causes rashes to appear on hands and feet
    • Rocky mountain spotted fever (Rickettsia rickettsii)
    • Syphilis (Treponema pallidum)
    • Hand foot and mouth (Coxsakie A virus)
  339. When do Coxsakie infections most commonly occur
    During summer months
  340. What does Coxsakie B infection cause
    • Dilated cardiomyopathy
    • Bornholm?s disease = pleurodynia = devil?s grip
  341. What is a devastating sequela of Coxsakie B infection?
    Dilated cardiomyopathy
  342. What is the clinical presentation of Bornholm?s disease caused by Coxsakie B infection?
    • Devils grip
    • Extreme sharp unilateral pain in lower chest
    • Difficulty breathing
  343. What does pleurodynia mean
    • Bornholm?s disease caused by Coxsakie B infection
    • Pleura of the lung
    • Dynia = pain
  344. How do we treat Coxsakie virus infections?
    Supportive treatment
  345. What kind of virus is arbovirus?
    Enveloped positive sense RNA virus
  346. What family is arbovirus from
    Togaviruses
  347. What is arbovirus short for
    Arthropod born virus
  348. What are common arthropod vectors
    Mosquitos
  349. What types of arboviruses are there?
    • Western equine encephalitis
    • Eastern equine encephalitis
    • Venezuelan equine encephalitis
  350. Where are the different arboviruses found?
    • Western equine encephalitis ? western USA
    • Eastern equine encephalitis ? eastern USA
    • Venezuelan equine encephalitis ? central and south America
  351. What do arboviruses cause
    Encephalitis
  352. What is encephalitis
    Inflamed brain
  353. What is the clinical presentation of encephalitis caused by arboviruses?
    • Headache
    • Fever
    • Altered mental status
    • Focal neuro deficits
  354. What is the treatment for arbovirus?
    No treatment
  355. How do you prevent arbovirus infection?
    • Netting
    • Bug spray
    • Protective coverings
  356. What is HPV
    Human Papillomavirus
  357. What kind of virus is papillomavirus?
    Naked double stranded DNA viruses
  358. What is the only single stranded DNA virus?
    Parvovirus
  359. What are the different types of human papillomavirus?
    • Over 100 different types
    • Most important are HPV 1-4, 6, 11, 16, 18, 31, 33
  360. What do human papillomaviruses 1-4 cause?
    Verruca vulgaris = cutaneous common wart on hands and feet of children
  361. Who is most affected by verruca vulgaris caused by human papillomaviruses 1-4
    Children
  362. How are human papillomaviruses 1-4 transmitted?
    Through physical contact
  363. What do human papillomaviruses 6 and 11 cause?
    • Laryngeal papillomatosis = recurrent respiratory papillomatosis
    • Condyloma acuminata =Ano-genital warts
  364. What is recurrent respiratory papillomatosis causes by human papillomaviruses 6 and 11
    • = laryngeal papillomatosis
    • Condition where tumors or papillomas develop in the airway
  365. Who is most affected by recurrent respiratory papillomatosis causes by human papillomaviruses 6 and 11
    Children
  366. How are human papillomaviruses 6 and 11 transmitted?
    • acquired during vaginal birth --> laryngeal papillomatosis
    • sexually transmitted --> condyloma acuminata
  367. What is condyloma acuminata caused by human papillomaviruses 6 and 11
    Anogenital warts
  368. What causes condyloma lata
    Syphilis
  369. What causes condyloma acuminata
    Human papillomaviruses 6 and 11
  370. Who is most affected by condyloma acuminata caused by human papillomaviruses 6 and 11
    Sexually active individuals
  371. What do human papillomaviruses 16 and 18 cause?
    Anogenital squamous cell carcinomas
  372. What kinds of cancers can human papillomaviruses 16 and 18 cause?
    • Anal
    • Cervical
    • Vulvar
    • Vaginal
    • Penile
  373. Which cells do human papillomaviruses infect
    Squamous cells found on skin and some areas of anus and cervix
  374. What strains of human papillomaviruses cause squamous cell carcinomas?
    • HPV 16
    • HPV 18
    • HPV 31
    • HPV 33
  375. How are human papillomaviruses 16, 18, 31, and 33 transmitted
    Sexual transmission
  376. How can we prevent anogenital carcinoma caused by HPV 16, 18, 31, 33?
    • Condoms
    • Abstinence
    • Vaccine
  377. Which strains of human papillomaviruses are covered by the HPV vaccine
    6, 11, 16, 18
  378. What causes most cervical cancers
    Human papillomaviruses 16 and 18
  379. What is Gardasil
    Human papillomavirus vaccine against strains 6, 11, 16, 18
  380. What kind of vaccine is the human papillomavirus vaccine?
    Inactivated subunit vaccine
  381. Who should be vaccinated against human papillomaviruses
    Women and men between ages 9-26 regardless of sexual activity
  382. What is the most common sexually transmitted disease?
    Human papillomavirus
  383. How are human papillomaviruses 16, 18, 31, and 33 able to cause cancer
    • Able to disrupt the regulation of the cell cycle
    • E6 promote proteolysis of p53 tumor suppressor protein
    • E7 promote proteolysis of Rb tumor suppressor proteins
    • Infected cells loose the G1-->S checkpoint
    • Leads to uninhibited cell growth --> neoplasia
  384. What are p53 and Rb
    Tumor suppression proteins
  385. What is the role of tumor suppression proteins?
    • Inhibit transition from G1 --> S phase
    • P53 serves as checkpoint that can arrest growth if there is a problem with the genome
  386. What is the clinical presentation of cervical cancer caused by HPV 16, 18, 31, and 33?
    Post coital bleeding
  387. How do we diagnose human papillomavirus infections?
    Pap smears ? screen cervical cancer
  388. How does a pap smear work?
    • Take sample of cervical cells form transformation zone
    • Visualize them under microscope
    • Cervical cancer cells have distinct features that can be detected under the microscope = koilocytes

    • What is the transformation zone?
    • Area where squamous epithelium from outer portion of the cervix (ectocervix) comes into contact with the columnar epithelium from the inner portion of the cervix (endocervix)
  389. What are koilocytes
    • Squamous cells infected with human papillomavirus that undergo morphological changes
    • Large dense wrinkled nuclei
    • Sometimes binucleated
  390. What is an important risk factor for development of cervical cancer due to HPV 16, 18, 31 and 33?
    • Immunosuppression
    • HIV positive people
  391. Why are HIV patients at particular risk of developing cervical cancer?
    HIV is thought to increase HPV E6 and E7 expression
  392. What kind of virus is poxvirus?
    Enveloped double stranded DNA virus
  393. how does poxvirus replicate
    • all equipment needed for replication is found within the virion
    • has special DNA dependent RNA polymerase already in the virion
    • so able to make mRNA in the cytoplasm
    • ribosomes translate the mRNA into proteins
    • DNA polymerase is encoded and therefore also translated so doesn?t have to go into the nucleus
  394. what is special about poxviruses
    • have all the equipment they need in their virion
    • make their own envelopes
    • replicates in the cytoplasm
  395. where do poxviruses replicate
    cytoplasm ? the only DNA virus that does this
  396. why are poxviruses able to replicate in the cytoplasm
    has special DNA dependent RNA polymerase
  397. what does poxvirus look like under microscope?
    • intracytoplasmic inclusions bodies in the cells that they infect
    • type B inclusions = guarnieri bodies
  398. what are guarnieri bodies
    poxvirus cytoplasmic inclusions representing sites of viral replication
  399. how do we diagnose poxvirus infection?
    microscopic analysis of biopsy of skin lesion
  400. what do we look for in biopsy of poxvirus skin lesion?
    guarnieri bodies in cytoplasm of infected cells
  401. what is the shape of poxvirus core?
    dumbbell shape
  402. what is the largest known DNA virus?
    poxvirus
  403. what viruses are in the poxvirus family
    • smallpox virus
    • cowpox virus
    • molluscum contagiosum virus
  404. what does smallpox virus cause?
    variola
  405. what is the clinical presentation variola caused by smallpox virus?
    raised blisters on the skin and mucosal surfaces
  406. what is the difference between variola and varicella?
    • variola = smallpox ? lesions are all in same stage
    • varicella = chickenpox (varicella zoster) ? lesions are mixture of new blisters, ulcers healing scabs
  407. what does cowpox virus cause?
    similar symptoms to smallpox
  408. how is cowpox transmitted
    contact with infected cow udders
  409. how do we treat smallpox?
    vaccine
  410. what kind of vaccine is smallpox vaccine?
    live cowpox virus is used
  411. which virus was successfully eradicated worldwide
    smallpox
  412. who is vaccinated against smallpox
    no one because it is eradicated
  413. why is smallpox a potential bioweapon
    no one is vaccinated anymore
  414. what is the clinical presentation of molluscum contagiosum virus infection?
    • flesh colored dome shaped umbilicated lesions (with dimple in the middle)
    • found anywhere except on the palms and soles
    • often seen on trunk, axilla, antecubital fossa, popliteal fossa
  415. who is most affected by molluscum contagiosum virus
    • children ? many lesions
    • adults ? single umbilicated lesion
    • HIV / immunosuppressed patients ? diffuse
  416. how is molluscum contagiosum virus transmitted to adults
    sexual transmission
  417. what should you do if an adult present with diffuse molluscum contagiosum virus
    test for HIV
  418. what kind of viruses are coronaviruses?
    Enveloped positive sense RNA virus
  419. What is unique about coronaviruses
    Helical shaped capsule
  420. What does coronavirus cause
    • Common cold
    • Severe Acute Respiratory Syndrome (SARS)
    • Middle East Respiratory syndrome (MERS)
  421. What determines which disease coronavirus causes
    Different strains cause common cold, SARS and MERS
  422. What is the clinical presentation of SARS caused by coronavirus infection?
    • Severe Acute Respiratory Syndrome
    • Acute bronchitis --> acute respiratory distress syndrome
  423. How do we diagnose SARS caused by coronavirus infection?
    • Test for antibodies to SARS ? negative if there is absence of antibodies over 28 days
    • Confirmed with PCR
  424. What is considered a negative SARS test
    Absence of coronavirus SARS antibodies over 28 days
  425. How do we treat SARS caused by coronavirus?
    • Efficacy of treatments are variable
    • Broad spectrum antibiotics
    • Ribavirin
    • Corticosteroids
  426. Where do coronaviruses replicate
    In the cytoplasm
  427. What kind of virus is rhinovirus?
    Naked positive sense RNA virus
  428. What family is rhinovirus from
    Picornaviruses
  429. How is rhinovirus transmitted
    • Through inhalation
    • Fomites
  430. What makes rhinovirus unique amongst the picornaviruses
    • Is not transmitted fecal orally
    • Transmitted through respiratory tract
    • Acid labile
  431. Why is rhinovirus not transmitted fecal orally?
    Acid labile so cannot survive passing through stomach
  432. what biochemical properties does rhinovirus have?
    acid labile
  433. why is it important to wash your hands regularly?
    to prevent transmission of diseases via fomites (e.g. rhinovirus)
  434. how does rhinovirus enter the host cell?
    attaches to ICAM 1
  435. what conditions does rhinovirus prefer?
    cold temperatures (33oC)
  436. where does rhinovirus infect
    upper respiratory tract
  437. why does rhinovirus infect the upper respiratory tract?
    air is cooler and constantly flowing in and out acting as a natural air conditioner
  438. what does rhinovirus cause
    upper respiratory tract infection
  439. why are we unable to create a vaccine against common cold?
    • over 113 different serotypes of rhinovirus
    • difficult to make a vaccine that covers all of there
  440. how do we treat the common cold caused by rhinovirus?
    • no treatment
    • no vaccine
  441. What is hepatitis
    Inflammation of the liver
  442. What causes hepatitis
    • Hepatitis A
    • Hepatitis B
    • Hepatitis C
    • Hepatitis D
    • Hepatitis E
  443. What kind of virus is hepatitis A virus?
    Naked positive sense RNA virus
  444. What family is hepatitis A virus from
    Picornaviruses
  445. How is hepatitis A transmitted
    • Fecal oral route
    • Shed in feces and contaminates water supplies (direct)
    • Shell fish caught in contaminated water supplies (indirect)
  446. What does hepatitis A infection cause
    Hepatitis
  447. What are the biochemical properties of hepatitis A virus?
    Acid stable ? allows passage through the stomach
  448. Why is hepatitis A infection not so common in developed countries
    A lot of effort goes into purifying water our drinking water to eliminate hepatitis A
  449. How can you inactivate hepatitis A virus?
    • Chlorination
    • Bleach
    • UV irradiation
    • Boiling (85oC for over a minute)
  450. Why are hepatitis A infections common in developing countries
    Lack of water purification
  451. What is the common means of transmission of hepatitis A in developed countries?
    Indirect ? uncooked contaminated shellfish
  452. Who is most affected by hepatitis A in developed countries
    Travelers who travel to endemic areas
  453. Where is hepatitis A most found in the world
    Southern hemisphere
  454. What is the clinical presentation of hepatitis A infection?
    • Often clinically silent or subclinical
    • Can be anicteric ? without jaundice ? often in children
    • Can cause acute viral hepatitis
    • * Fever
    • * hepatomegaly
    • * jaundice ? especially in adults
    • aversion to smoking tobacco products
  455. what is special about acute viral hepatitis caused by hepatitis A
    smokers who get the infection develop an aversion to smoking tobacco products
  456. how long do symptoms occur in hepatitis A infection
    1-month long illness
  457. how do we treat hepatitis A infection?
    • often self-limited
    • no carrier or chronic state
    • vaccine
  458. what is the chronic state of hepatitis A infection?
    • there is none
    • also no carrier state
  459. what kind of vaccine is hepatitis A vaccine?
    inactivated vaccine
  460. who should be vaccinated against hepatitis A
    • people in endemic areas
    • people with chronic liver disease
    • men who have sex with men
    • travelers
  461. what kind of virus is hepatitis C virus?
    Enveloped positive sense RNA virus
  462. What family is hepatitis C virus in
    Flaviviruses
  463. How is hepatitis C virus transmitted?
    • Exposure to infected blood or bodily fluids
    • Blood transfusions
    • IV drug users who share needles
    • Placenta
    • Sex
    • Breast feeding
  464. How did hepatitis C used to be passed in the hospital setting before 1990?
    Through blood transfusions
  465. Which hepatitis can be contracted through sex
    • Hepatitis B ? more common
    • Hepatitis C ? also possible
  466. Why is it difficult to create a vaccine against hepatitis C?
    Envelope proteins often vary antigenic structures so immune system can?t keep up
  467. How does antigenic variation in hepatitis C occur?
    • Virion encoded RNA polymerase lacks proof reading exonuclease activity in 3?-->5? direction
    • RNA is prone to frequent mutations
    • Meaning structure of protein is also prone to frequent changes
  468. What does hepatitis C cause?
    • Acute Hepatitis
    • Chronic hepatitis
  469. What is the clinical presentation of acute hepatitis C infection?
    • Jaundice
    • Red upper quadrant pain or discomfort
    • Enlarged liver
    • Increased liver enzymes
  470. What is the difference between hepatitis B and C infection?
    • Hepatitis B infection resolves after acute attack
    • Hepatitis C causes chronic infections
  471. How common is chronic hepatitis C infection
    60-80% infections
  472. How does hepatitis C chronic infection progress?
    • Lymphocytes infiltrate portal tract
    • Chronic inflammation and infection of hepatocytes and parenchyma
    • This will cause hepatocytes to die
    • Liver must quickly replace dead hepatocytes
    • Some parts will succumb to fibrosis and cirrhosis
    • Or liver can go into frenzy and reproducing cells become malignant
    • What happens in chronic hepatitis C infection
    • Some parts of the liver succumb to fibrosis and cirrhosis
    • Liver goes into frenzy to replace dyeing cells and reproducing cells become malignant
  473. What can cause hepatocellular carcinoma
    Chronic Hepatitis C infection
  474. How do you diagnose an acute hepatitis C infection?
    • hepC RNA in serum during first 6 months
    • ALT will rise and fall within first 6 months
    • Anti HCV will rise after 2-3 months of getting over an acute infection
  475. Why is there a 2-3-month lag in production of anti HCV antibodies?
    Due to new mutant strains being produced thanks to the antigenic variation
  476. Why do you find anti HCV in both acute and chronic hepatitis C infections?
    Virus mutates very fast so antibodies produced soon become ineffective
  477. Why is it possible to get recurring hepatitis C infections?
    Mutation in the virus due to antigenic variation means antibodies produced may not protect anymore
  478. How do you diagnose a chronic hepatitis C infection?
    • Viral hepC RNA persists in the serum after 6 months
    • Liver biopsy will show a lot of lymphocytes in portal tract
  479. What are cryoglobulins
    Serum proteins containing immunoglobulins (mostly IgM) that will precipitate out in cooler temperatures
  480. Which hepatitis virus is associated with cryoglobulins
    Hepatitis C
  481. How do you treat hepatitis C infection?
    • Ribavirin + interferon alpha
    • Protease inhibitors ? genotype testing must be done to determine combination
    • Sofosbuvir
  482. What is sofosbuvir and what is it used for
    • Polymerase inhibitor
    • Treatment of hepatitis C
  483. What do proteases do
    Cut protein
  484. Which protease inhibitors do we use to treat hepatitis C infection
    Genotype testing of the virus must be done to determine what combinations of drugs should be used
  485. What is the leading cause of liver transplants?
    Hepatitis C virus
  486. What kind of virus is hepatitis C virus?
    Enveloped circular partially double stranded DNA virus
  487. What family is hepatitis C virus from
    Hepadnaviruses
  488. What does hepadnavirus mean
    Hepatic DNA virus
  489. What makes hepatitis B unique among the DNA viruses
    • Replicates both inside and outside the nucleus
    • Genome is circular and partially double stranded
  490. Where does hepatitis B virus replicate
    Both in cytoplasm and in nucleus
  491. Which DNA virus is partially double stranded
    Hepatitis B virus
  492. When does hepatitis B DNA become fully double stranded
    During replication only
  493. How does hepatitis B DNA replicate?
    • Starts as a partially double stranded DNA molecule
    • Intermediate single stranded RNA
    • Back to double stranded DNA
  494. Which viruses carry reverse transcriptase
    • Hepatitis B virus
    • HIV
  495. What is the difference between hepatitis B viruses and retroviruses?
    • Retrovirus reverse transcriptase integrates them into the host chromosome
    • Hepatitis B virus reverse transcriptase does NOT integrate it into the host chromosome
  496. How is hepatitis B transmitted?
    • Sex
    • Sharing blood products
    • Sharing needles / needle stick in healthcare workers
    • Vertical transmission ? due to mixing of blood during delivery
  497. Why is hepatitis B not a TORCHeS pathogen?
    • Vertical transmission is not through infection in utero but through mixing of blood during delivery
    • The virus is too big to pass through the placenta
  498. What does hepatitis C virus infection cause?
    • Acute Hepatitis
    • Chronic hepatitis
    • Polyarteritis nodosa
    • Membranous Glomerular nephritis
    • Membranoproliferative glomerular nephritis
    • Prodromal serum sickness type illness with rash and arthralgia
  499. What is the clinical presentation of hepatitis caused by hepatitis B virus infection?
    • Inflammation of the liver = hepatitis
    • Right upper quadrant pain
    • Jaundice
  500. what hepatitis virus is more likely to cause chronic infection
    hepatitis C
  501. which hepatitis viruses can cause chronic infection
    hepatitis B and C
  502. how common is it for hepatitis B infection to become chronic?
    5-10%
  503. Who is most likely to develop chronic hepatitis B infection
    • Younger children
    • Newborns ? 90-95% chance
  504. What is the clinical presentation of polyarteritis nodosa caused by hepatitis B virus?
    • Systemic vasculitis that affects medium to small arteries
    • Causes small aneurysms to form on the arteries --> beads on a strong appearance
    • Reduced GFR and hypertension if the vessels of the kidney are affected
  505. What is the clinical presentation of prodromal hepatitis B infection?
    • Purpuric rash with non-blanching dark macules
    • Arthralgia ? pain in joints
  506. What are the possible renal diseases caused by hepatitis B?
    • Polyarteritis nodosa affecting vessels of the kidney
    • Membranous glomerulonephritis
    • Membranoproliferative glomerulonephritis
  507. What is the clinical presentation of membranous glomerulonephritis caused by hepatitis B?
    Extra thick glomerular basement membrane
  508. What is the clinical presentation of membranoproliferative glomerulonephropathy caused by hepatitis B?
    Deposits in the mesangium expanding into glomerular basement membrane causing tram track appearance
  509. How do we determine the stage of hepatitis B infection?
    • Liver enzymes
    • Serology
  510. What does viral hepatitis and alcoholic hepatitis have in common?
    Causes elevation in liver enzymes
  511. What is different in viral hepatitis and alcoholic hepatitis
    • Alcoholic ? AST greater than ALT
    • Viral ? ALT usually greater than AST
  512. What is the pattern of liver enzymes seen in hepatitis caused by hepatitis B infection?
    • Rise in ALT in acute infections
    • Fall in ALT after the symptomatic phase is over
    • EXCEPT in perinatal infection ? serum ALT may appear normal
  513. What are the levels of liver enzymes in the initial phase of perinatal hepatitis caused by hepatitis B infection?
    Normal despite the high levels of hepatitis B virus replication
  514. What do we measure in liver enzyme test?
    • ALT
    • AST
  515. What do we measure in serology for hepatitis B infection?
    • Titer levels of hepatitis B antigens and antibodies
    • HepB surface antigen ? marker of active disease
    • HepB E antigen ? correlates with infectivity
    • Anti hepB core antibody
    • Anti hepB e antibody
    • Anti hepB surface antibody
  516. What is the pattern seen on serology in acute infection hepatitis B?
    • hepB surface antigen is first to be clinically measurable
    • hepB e antigen is the next to appear
    • finally, body mounts an immune response and anti hepB surface antibodies bind hepB surface antigens so that neither is detectable
    • anti hepB core antibodies are also formed and are unbound at this point
    • anti hepB e antibody is formed
    • infection is resolved and hepB surface antibody is no longer found meaning anti hepB surface antibody is now freely found in the serum
  517. what is the marker for active hepatitis B disease (both acute and chronic)?
    hepB surface antigen
  518. how do we know if someone is contagious with hepatitis B?
    hepB e antigen is elevated
  519. what does the serology look like in symptomatic phase of hepatitis B infection?
    • high hepB Surface antigen
    • high hepB e antigen
  520. what is the window period in hepatitis B infection?
    • period when the patient has started to develop anti hepB surface antibodies and these start to bind hepB surface antigens
    • neither antigens nor antibodies are detectable in the phase
  521. what serological test can we perform during the window period to eliminate false negatives
    anti hepB core antibody is present
  522. when do we know that a patient has low infectivity (is not so contagious)
    increased anti hepB e antibody
  523. how do we know if a patient has recovered from hepatitis B infection?
    anti HepB surface antibody is seen
  524. how do we check for immunization against hepatitis B infection?
    anti HepB surface antibody is seen
  525. how do we treat hepatitis B infection?
    • most acute infections will clear up by themselves
    • nucleotide reverse transcriptase inhibitors (NRTIs) ? lamivudine ? antiviral (like in HIV)
    • interferon alpha therapy (like in hepC)
    • vaccination
  526. who do we treat for hepatitis B infection?
    • pregnant women
    • people who have progressed to chronic infection
  527. what does hepatitis B treatment do?
    • minimizes damage by preventing replication of hepatitis B virus
    • does NOT eradicate hepatitis B
  528. what do we do when a pregnant woman has hepatitis B infection?
    • nucleotide reverse transcriptase inhibitors (NRTIs) e.g. lamivudine given prior to delivery
    • give anti hepB immunoglobulins to newborn (passive immunity)
    • give hepB vaccination to newborn (active immunity)
  529. when do we give vaccine against hepatitis B infection?
    • at birth
    • given in 3 shots
  530. how can you tell an immunized patient apart from a patient who has been infected by hepatitis B in the past?
    • anti hepB surface antibody is present in both
    • anti hepB e antigen and anti hepB core antibody are only found in patients who have suffered from the infection
  531. what are the possible long term sequelae of chronic hepatitis B infection?
    • cirrhosis of the liver
    • hepatocellular carcinoma
  532. what kind of virus is hepatitis D?
    enveloped negative sense circular RNA virus
  533. what does hepatitis D cause?
    • cannot cause any disease without hepatitis B being present
    • co-infection of hepatitis B and D at the same time
    • superinfection of hepatitis D on top of an existing hepatitis B infection
  534. why is hepatitis D virus unable to infect cells on its own?
    require surface antigen of hepatitis B virus in order to cause infection
  535. what is the difference between hepatitis D coinfection and superinfection?
    • coinfection ? hepB and hepD are transmitted at the same time
    • superinfection ? HepB infection already exists and hepD infection is transmitted afterwards
  536. which type of hepatitis D infection has worse outcomes
    superinfection
  537. What does HIV stand for?
    Human Immunodeficiency Virus
  538. What kind of virus is HIV?
    • Enveloped Retrovirus
    • Enveloped positive sense RNA virus (diploid)
  539. What does HIV cause
    Acquired Immunodeficiency syndrome (AIDS)
  540. How is HIV replicated
    • Positive RNA strand is converted into DNA intermediate by accompanying enzyme reverse transcriptase
    • Once DNA intermediate is formed it can become incorporated into host chromosomes and replicate forever
  541. What does reverse transcriptase do
    Converts retrovirus positive RNA strand --> DNA intermediate
  542. How many strands of RNA are in HIV?
    2 strands of positive sense RNA = diploid virus
  543. Which genes does HIV use for replication
    • Env- envelope
    • Gag ? capsule
    • Pol ? polymerase = reverse transcriptase
  544. What is the gag gene used for in HIV replication?
    • Gene that makes the protein p24
    • P24 protein serves as a capsule for the RNA strands of HIV
  545. What is the capsule of HIV made of and what is its shape?
    • P24
    • Cone shaped
  546. What is the env gene used for in HIV replication
    • Responsible for making the glycoprotein 160
    • This is cleaves into glycoproteins 41 and 120
    • These proteins serve to form a viral envelope
  547. What is the envelope of HIV made of?
    Glycoproteins 41 and 120
  548. What is the transmembrane protein on HIV envelope?
    Glycoprotein 41
  549. What is the outer protein on HIV envelope?
    Glycoprotein 120
  550. Which part of the HIV envelope comes into contact with host receptors
    Glycoprotein 120
  551. What is the pol gene used for in HIV replication?
    Polymerase = reverse transcriptase
  552. How is HIV transmitted
    • Primarily through sexual contact
    • Vertical transmission
    • Blood ? IV drug users
  553. What are the TORCHes organisms?
    • Can cross placenta and infect fetus in utero
    • T ? Toxoplasma Gondi
    • O ? Other (varicella zoster, parvovirus b19)
    • R ? Rubella
    • C ? Cytomegalovirus (CMV)
    • H ? Herpes simplex virus (HSV) and human immunodeficiency virus (HIV)
    • S ? syphilis
  554. What cells does HIV target?
    • Macrophages
    • Helper T cells = CD4+ cells
  555. How does HIV infection progress?
    • Primary infection
    • Latent period
    • AIDS
  556. What is the clinical presentation of primary HIV infection?
    • Prodrom
    • Flu or mono like symptoms
    • Cervical lymphadenopathy
    • Tonsils enlarge
    • Fever
  557. How long does HIV primary infection last?
    Several weeks then gets better on its own
  558. How long can the latent HIV infection last
    Up to 10 years
  559. What happens during the latent HIV infection?
    HIV virus is replicating in the lymph nodes
  560. When does latent HIV infection to become AIDS
    • CD4+ cell count drops below 200
    • AIDS defining illness present
  561. What does AIDS stand for?
    Acquired Immune Deficiency Syndrome
  562. What is an AIDS defining illness caused by HIV directly?
    Diffuse large B cell lymphoma
  563. How does HIV infect its host?
    • Fusion of virus with macrophages and helper T cells via CCR5 and CXCR4 receptors on the host cell
    • Virus enters the cells and uncoats
    • undergoes reverse transcription
    • gets incorporated into host DNA
    • Makes new virions using host machinery
  564. Which receptors on the host cell does HIV target
    CCR5 and CXCR4 co-receptors
  565. Which receptors does HIV use in the early stages of the infection
    CCR5 receptors of macrophages and T helper cells
  566. Which receptors does HIV use in later stages of the infection
    CXCR4 receptors of macrophages and T helper cells
  567. How do we diagnose HIV infection?
    • Multiple screening tests done over 6-month period after possible exposure ? ELISA
    • Confirmation test ? western blot
    • Viral load and CD4 count ? PCR
    • HIV RNA and HIV DNA nucleic acid amplification test
  568. What does the ELISA test look for?
    Tests for antibodies
  569. Why might we get a false negative in an ELISA test
    If tested too early antibodies are not formed yet
  570. In what situation do we do confirmation test for HIV infection
    After positive ELISA test result
  571. What is a western blot?
    Gel electrophoresis to separate proteins in specific pattern
  572. What do we do once someone is diagnosed with HIV?
    Measure viral load and CD4 count
  573. How do we measure viral load and CD4 count?
    PCR
  574. Why are neonates from HIV positive mothers always positive when screened
    • ELISA and western blot test for antibodies
    • Neonates have mother?s antibodies (passive immunity)
  575. When do we do HIV RNA and HIV DNA nucleic acid amplification test
    To test neonate with HIV positive mother
  576. How do we test a neonate with HIV positive mothers?
    HIV RNA and HIV DNA nucleic acid which looks for virus directly instead of antibodies
  577. How do we treat HIV infection?
    • Highly Active Anti-Retroviral Therapy (HAART)
    • Nucleoside Reverse Transcriptase Inhibitors (NRTI) = Zidovudine
    • Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTI)
    • Protease inhibitors
    • CCR5 blocker = Maraviroc
  578. Why do we use combination therapy to treat HIV infection?
    HIV is prone to mutation and developing resistance
  579. What are NRTIs
    Nucleoside reverse transcriptase inhibitors used to treat HIV
  580. How do NRTIs work
    • Pose as nucleotide and get incorporated into the DNA of HIV by the reverse transcriptase
    • Halt farther elongation
  581. What is Zidovudine
    1st NRTI made
  582. When do we use zidovudine?
    • Pregnant women
    • During labor
    • Post partem
    • 14 weeks of gestation --> 6 weeks post partem
    • Reduced risk of transmission to baby by 2/3
  583. What are NNRTIs
    Non-Nucleoside Reverse Transcriptase Inhibitors used to treat HIV
  584. How do NNRTIs work
    Inhibits reverse transcriptase
  585. How do protease inhibitors work?
    Stops cleavage of proteins necessary for viral replication
  586. How does maraviroc work
    • CCR5 blocker
    • Prevents fusion of virus with host cells
  587. How do you decide what combination of therapy to give a patient?
    Genotype testing of HIV strains to find best combination
  588. Who do we treat for HIV?
    • Everyone should be treated to prevent high viral loads and low CD4 counts
    • CD4 counts <350
    • Pregnant women
    • Those with high viral loads
  589. What kind of viruses are there?
    • RNA / DNA
    • Naked / Enveloped
    • Replicate in cytoplasm / Replicate in nucleus
  590. What kind of RNA viruses are there?
    • Positive sense
    • Negative sense
  591. What does ?naked virus? mean
    Lacks viral envelope
  592. How does fecal oral transmission of viruses occur
    • Viruses shed in feces
    • Viruses end up in food and water or hands of children
    • Virus is introduced into he mouth
  593. How do positive sense RNA viruses replicate?
    • Viral RNA is same sense as host cell mRNA
    • Can be translated into proteins directly by the host cell RNA polymerase
    • Virus can use entirely the host cell?s machinery to translate RNA --> long polyprotein product
    • Viral proteases cleave long polyprotein product into active viral protein subunits
  594. What cleaves long polyprotein product of positive sense RNA virus translation
    Viral proteases
  595. Where do all positive sense RNA viruses replicate?
    In the cytoplasm outside of the nucleus
  596. Where do most negative sense RNA viruses replicate
    In the cytoplasm outside of the nucleus
  597. What are the 5 main types of hepatitis?
    • Hepatitis A ? picornavirus
    • Hepatitis B
    • Hepatitis C
    • Hepatitis D
    • Hepatitis E
  598. What is the clinical presentation of hepatitis?
    Hepatosplenomegaly
  599. How are negative sense RNA viruses replicated?
    • Must be transcribed into positive sense RNA using their own RNA polymerase
    • Needs to bring along its own viral RNA polymerase
  600. What is the only double stranded RNA virus?
    Reovirus
  601. Where do RNA viruses replicate
    Cytoplasm
  602. What is the only RNA virus that does not replicate in the cytoplasm?
    Orthomyxovirus ? in the nucleus
  603. What kind of viruses are Picornaviruses?
    Naked Positive sense RNA viruses
  604. How are Picornaviruses transmitted
    Fecal oral route
  605. Which picornavirus is not transmitted through fecal oral route
    Rhinovirus
  606. How is the rhinovirus transmitted?
    Through the respiratory system
  607. How do picornaviruses replicate
    • Positive sense RNA
    • Viral RNA already structured like mRNA
    • Uses host RNA polymerase to be translated into long polyprotein product
    • Viral proteases cleave long polyprotein product into active viral protein subunits
  608. What is the function of the long polyprotein product of positive sense RNA virus translation?
    • No function
    • Must be cleaved
  609. What cleaves picornavirus long polyprotein product of positive sense RNA virus translation
    Viral proteases
  610. Where do picornaviruses replicate
    In the cytoplasm outside of the nucleus
  611. Which viruses are part of the picornavirus family
    • Hepatitis A
    • Enteroviruses
    • Rhinoviruses
  612. What family is Hepatitis A virus from
    Picornavirus
  613. Which viruses are part of the enterovirus group
    • Poliovirus
    • Coxsakie A and B
    • Echovirus
  614. What is the number one cause of aseptic meningitis?
    Enteroviruses
  615. What is aseptic meningitis
    Meningitis caused by a nonbacterial organism
  616. What are cerebro spinal fluid findings of a viral meningitis
    • Glucose levels are normal
    • No organisms = aseptic
    • Protein levels elevated
  617. Who is most affected by viral meningitis caused by enteroviruses
    Children
  618. What is the primary cause of the common cold?
    Rhinoviruses
  619. What do rhinoviruses cause
    Upper respiratory infections (URI)
  620. What kind of viruses are flaviviruses?
    Enveloped positive sense RNA virus
  621. What viruses are in the flavivirus family
    • Hepatitis C
    • Dengue virus
    • Yellow fever virus
    • West Nile virus
  622. How are flavivirus RNA strands
    Non segmented
  623. What does dengue virus cause?
    Dengue fever = break bone fever
  624. What is the clinical presentation of dengue fever caused by dengue virus?
    • Sweating Feverish
    • Thrombocytopenia --> increased risk of bleeding (hemorrhagic fever)
    • Renal failure
    • Septic shock --> death
  625. How is dengue fever transmitted?
    Arthropod vectors ? Aedes Egyptei mosquitos
  626. What is the vector for dengue fever?
    Aedes Egyptei mosquitos
  627. What is the target for dengue virus?
    Infects bone marrow
  628. How many types of dengue fever are there?
    4 (types 1-4)
  629. What is hemorrhagic fever
    Fever with increased risk of bleeding due to thrombocytopenia
  630. What is a cause of hemorrhagic fever?
    Dengue virus
  631. What is a serious complication of dengue fever?
    • Renal failure
    • Septic shock --> death
  632. How do we treat dengue fever caused by dengue virus?
    • Supportive treatment ? hydration therapy
    • No treatment
    • No vaccine
  633. What does yellow fever virus cause?
    Yellow fever
  634. How is yellow fever virus transmitted?
    Arthropod ? Aedes Egyptei mosquito
  635. What is the vector for yellow fever virus?
    Aedes Egyptei virus
  636. What is the clinical presentation of yellow fever caused by yellow fever virus?
    • Jaundice
    • Back ache
    • Bloody diarrhea and bloody vomiting
  637. What is the treatment for yellow fever virus?
    • No treatment
    • Live attenuated vaccine
  638. What kind of vaccine is the yellow fever virus vaccine?
    Live attenuated vaccine
  639. How is west Nile virus transmitted?
    Arthropod vector ? Culex mosquito
  640. What is the vector for west Nile virus?
    Culex mosquitos
  641. What is the reservoir for west Nile virus?
    Birds
  642. What is the major complication of west Nile virus infection?
    Encephalitis
  643. What does west Nile virus cause
    • Encephalitis
    • Myelitis --> flaccid paralysis
  644. What is the clinical presentation of west Nile virus infection?
    • Flaccid paralysis
    • Eventually seizures and coma
  645. How do you diagnose west Nile virus infection?
    PCR + serology of cerebrospinal fluid
  646. How do we treat west Nile virus?
    • Supportive therapy
    • No treatment
    • No vaccine
  647. What does rhabdovirus cause
    Rabies
  648. What kind of virus is rhabdovirus?
    Enveloped negative sense RNA virus
  649. What does the rhabdovirus envelope look like
    Bullet shaped
  650. What shape is the rhabdovirus nucleocapsid
    Helical
  651. How is rhabdovirus transmitted
    Zoonotic virus ? bats, squirrels, foxes, rodents
  652. What a zoonotic infection
    Carried by animals and transmitted to humans
  653. What do rhabdoviruses target
    Have a glycoprotein that binds to nicotinic acetylcholine receptors in the post synaptic membrane of the neuromuscular junction
  654. Where does rhabdovirus replicate
    Motor neurons cytoplasm
  655. How does rhabdovirus cause infection
    • Virus targets post synaptic membrane of motor end plate
    • Replicates in motor neurons
    • Travels in retrograde direction via peripheral nerves to dorsal root ganglia and spreads to brain

    • What is the clinical presentation of rhabdovirus infection?
    • Incubation period of weeks to months
    • Tingling and muscle spasms as rhabdovirus travels along peripheral nerves
    • Increased salivary production once reaches salivary glands
    • Excruciating spasm of muscles in the throat and larynx --> dysphagia
    • Foaming at the mouth
    • High fever
    • Encephalitis
    • Neuronal death
    • Almost always fatal
  656. How long is the incubation period for rhabdovirus and what does it depend on?
    • Weeks to months
    • depending on the distance of the site of inoculation to the CNS
  657. how fast does rhabdovirus move along peripheral nerves
    1-3 mm per day
  658. How do we diagnose rhabdovirus infection?
    • Clinical observation of symptoms of rabies
    • Positive history of exposure
    • Confirmed on biopsy / autopsy
  659. How do we confirm rhabdovirus infection?
    Negri bodies in the brain
  660. What are Negri bodies
    • Eosinophilic cytoplasmic inclusions found either
    • within the soma of purkinje cells in the cerebellum or
    • in pyramidal cells of hippocampus
  661. how do we treat rabies caused by rhabdovirus?
    • antidote = passive immunization
    • AND active immunization with killed vaccine
    • administered prior to onset of symptoms and as soon as possible after exposure
  662. what kind of vaccine is the rhabdovirus vaccine?
    • Passive ? human rabies immunoglobulin
    • Active ? killed viral particles
  663. Who do we vaccinate against rhabdovirus?
    People after they have been bitten by animals suspected to be infected with rabies
  664. What kind of viruses are filoviruses?
    Enveloped negative sense RNA viruses
  665. What shape is the nuclear capsid of filoviruses
    Helical
  666. Where do filoviruses replicate
    Cytoplasm
  667. What viruses are in the filovirus family
    • Ebola virus
    • Marburg virus
  668. What kind of virus is Ebola?
    Enveloped negative sense RNA virus
  669. What family is Ebola part of
    Filoviruses
  670. What is the clinical presentation of filovirus infection?
    • Hemorrhagic Fever ? Sweating, redness, petechiae (start days ? weeks after contracting virus)
    • Eventually end organ failure
    • Usually fatal due to sever blood loss --> hypovolemic shock
  671. How are filoviruses transmitted
    • Direct contact with animal infected with the virus
    • Bodily fluids especially after death of individual
  672. What are endemic areas for filoviruses
    Africa
  673. What is the reservoir for filoviruses?
    • Fruit bats probably
    • Primates
  674. Who is affected by filoviruses
    • People in contact with monkeys or bats in endemic areas
    • Healthcare workers taking care of infected individuals
  675. Why must we be cautious in handling of bodies after filovirus infections
    Infection can be passed through contact with bodily fluids even after death
  676. What kind of viruses are bunyaviruses?
    Enveloped negative sense circular RNA viruses
  677. How do bunyaviruses obtain their envelope?
    From the Golgi complex of host cells
  678. How many segments do bunyaviruses have?
    3 circular segments
  679. Which viruses are segmented
    • BOAR
    • Bunyavirus
    • Orthomyxovirus
    • Arenavirus
    • Reovirus
  680. What are arboviruses
    Arthropod born viruses
  681. How are bunyaviruses transmitted
    • Arthropod vectors ? Aedes mosquito
    • Except hantavirus ? contact with rodents or their excrement
  682. Which viruses are in the bunyavirus family
    • Hantavirus
    • Rift valley fever virus
    • California encephalitis virus
  683. Which family does hantavirus belong to
    Bunya virus
  684. What kind of virus is hantavirus?
    Enveloped negative sense RNA virus
  685. What is the reservoir of hantavirus?
    Rodovirus = rodent born virus ? dear mouse
  686. What viruses are part of hantavirus groups
    Sine nombre
  687. How is hantavirus transmitted
    Contact with rodents or their excrement
  688. What does hantavirus cause
    • Pulmonary edema via capillary leak
    • Prerenal azotemia (nitrogen in blood) because there is a low volume of blood
    • Hemorrhagic fever ? feverish and sweating
  689. What do rift valley fever and California encephalitis viruses cause
    • Neurological problems ? seizure, encephalitis, myalgia, fever
    • Not usually fatal
  690. What kind of virus is arenavirus?
    Enveloped ambi-sense circular RNA virus
  691. Where do arenaviruses replicate
    Cytoplasm
  692. What does ambisense virus mean
    Has the capacity to encode both negatively and positively
  693. What shape is arenavirus nucleocapsid
    Helical shaped
  694. What negative sense RNA viruses have helical shaped nucleocapsids?
    • Arenavirus
    • Filovirus
    • Rhabdovirus
  695. Which viruses have segmented RNA
    • BOAR
    • Bunyavirus
    • Orthomyxovirus
    • Arenavirus
    • Reovirus
  696. How many segments of RNA does arenavirus have?
    2 circular segments
  697. What does arenavirus look like when visualized using electron microscopy?
    Characteristic sandy look
  698. What does arenavirus mean
    • Sand virus
    • Because it looks like sand when looked at through electron microscopy
  699. How is arenavirus transmitted
    Rodent transmitted disease to human
  700. What viruses are in the arenavirus family
    Lymphocytic Choriomeningitis Virus (LCV)
  701. What does LCV cause
    Febrile aseptic meningoencephalitis
  702. How do we inactivate arenavirus to prevent infection?
    Kill virus by heating. Low pH, irradiation and detergents
  703. What kind of viruses are reoviruses?
    Non enveloped double stranded RNA viruses
  704. Where do reoviruses replicate
    Cytoplasm
  705. Which viruses have segmented RNA
    • BOAR
    • Bunyavirus
    • Orthomyxovirus
    • Arenavirus
    • Reovirus
  706. How many segments do reoviruses have?
    • Between 9-12 segments
    • 11 segments
  707. What kinds of viruses are in the reovirus family?
    Rotavirus
  708. What kind of virus is rotavirus?
    Enveloped double stranded RNA virus
  709. What family is rotavirus part of
    • Reoviruses
    • Colorado tick virus
  710. How is rotavirus transmitted
    Fecal oral route
  711. What does rotavirus cause
    Toxin mediated secretory explosive watery diarrhea
  712. How does rotavirus cause diarrhea?
    • Toxin mediated
    • NSP4 viral enterotoxin increases chloride permeability --> secretory diarrhea
  713. What virulence factors does rotavirus have
    NSP4 toxin viral enterotoxin
  714. When do rotavirus outbreaks occur
    Wintertime
  715. Who is most affected by rotaviruses
    • Children
    • Often infants in daycare
  716. What is the leading cause of severe diarrhea in infants and children?
    Rotavirus
  717. What does Colorado tick virus cause?
    • Fever
    • Vomiting
    • Myalgia
    • No rash
  718. Where does Colorado tick virus cause infection
    Rocky mountain
  719. How do you differentiate between rocky mountain spotted fever virus and Colorado tick virus?
    • Rocky mountain spotted fever causes a rash (that starts at extremities and spreads centrally) ? rickettsia rickettsii
    • Colorado tick virus does not cause a rash ? virus
  720. how do you treat rotavirus?
    • supportive care with oral rehydration therapy
    • vaccine
  721. what kind of vaccine is rotavirus vaccine?
    live attenuated oral vaccine
  722. when is of rotavirus vaccine given
    first dose ? before 3 months old (decreased efficacy and increased side effects)
  723. what are the risks associated with rotavirus vaccine?
    increased risk for intussusception due to stimulation and enlargement of peyers patches which cat as lead point
  724. what is intussusception
    like telescoping of the bowel
  725. What is HHV 8
    Human herpes virus 8
  726. What kind of virus is human herpes virus 8?
    Enveloped double stranded linear DNA virus
  727. What family does human herpes virus 8 belong to?
    Herpesviruses
  728. What does human herpes virus 8 cause?
    • Kaposi sarcoma
    • Primary Effusion lymphoma
  729. What should you do if you see a patient with Kaposi sarcoma caused by human herpes virus 8
    Test for aids
  730. What is Kaposi sarcoma caused by human herpes virus 8 associated with
    AIDs and immunosuppression
  731. What is the clinical presentation of Kaposi sarcoma caused by human herpes virus 8?
    • erythematous violaceous lesions on the nose, extremities, mucous membranes
    • can be present as a plaque, patch, macule or nodule
    • can be cutaneous or mucosal lesions (in the gastrointestinal tract)
  732. what are Kaposi sarcoma lesions made of?
    primitive vasculature forming mesenchymal cells
  733. what is the pathogenesis of Kaposi sarcoma lesions?
    • infection with human herpes virus 8
    • virus causes dysregulation of vascular endothelial growth factor (VEGF)
    • this causes abherent angiogenesis
    • newly formed blood vessels within lesions cause violaceous color
  734. how does human herpes virus 8 cause angiogenesis?
    dysregulation of Vascular endothelial growth factor (VEGF)
  735. what is the most common location for Kaposi lesions caused by human herpes virus 8 to occur?
    hard palate
  736. what is primary effusion lymphoma
    B cell lymphoma caused by human herpes virus 8
  737. How is human herpes virus 8 transmitted?
    Sexual contact including contact
  738. Who is most affected by human herpes virus 8 infection
    • Men who have sex with men
    • HIV AIDs
    • Elderly Russian men
    • People in areas of Africa where areas are endemic
  739. What kind of Kaposi lesions caused by human herpes virus 8 do elderly Russian men have?
    Lower extremity lesions
  740. Where is human herpes virus 8 endemic?
    Areas of Africa
  741. How do adults in Africa present with human herpes virus 8 infection
    Palatal Kaposi lesions
  742. How do children in Africa present with human herpes virus 8 infection
    Could be fatal
  743. What is the differential diagnosis for Kaposi sarcoma caused by human herpes virus 8?
    Bacillary angiomatosis caused by Bortonella hensleae (cat scratch disease)
  744. How do you diagnose Kaposi lesion caused by human herpes virus 8?
    Microscopic examination
  745. How do you differentiate between Kaposi sarcoma and bacillary angiomatosis?
    • Kaposi sarcoma ? HHV8 ? accompanied by lymphocytic infiltrate
    • Bacillary angiomatosis ? Bartonella hensleae ? accompanied by neutrophilic infiltrate
  746. How do we treat Kaposi sarcoma caused by human herpes virus 8?
    Antiretroviral therapy should be started in HIV positive patients
  747. What kind of viruses are polyomaviruses?
    Naked double stranded circular DNA viruses
  748. What viruses are in the polyomavirus family
    • john Cunningham (JC) virus
    • BK virus
  749. What does JC virus cause?
    Progressive multifocal leukoencephalopathy (PML)
  750. How frequent is JC virus in the population?
    Over half of the population has it
  751. Who is affected by progressive multifocal leukoencephalopathy caused by JV virus
    • Immunocompromised people
    • HIV patients with CD4 counts <200
  752. What is progressive multifocal leukoencephalopathy caused by JC virus
    • Demyelinating disease
    • Kills oligodendrocytes that produce myelin for CNS
    • Affects the white matter of the brain
  753. How long does progressive multifocal leukoencephalopathy caused by JC virus last
    Half patients die within a few months
  754. What do we see in brain imaging of progressive multifocal leukoencephalopathy caused by JC virus?
    Brain lesions that light up
  755. What kinds of brain lesions do we see in PML caused by JC virus?
    Non enhancing lesions
  756. How do we differentiate brain lesions caused by toxoplasma and JC virus?
    • JC lesions ? non enhancing lesions
    • Toxoplasma Gondi ? ring enhancing lesions
  757. Which part of the brain is affected by JC virus
    White matter ? leukoencephalopathy
  758. What does BK virus cause?
    • Nephropathy
    • other urinary tract problems ? hemorrhagic cystitis
  759. what viruses cause bright red hemorrhagic urine
    • BK virus ? hemorrhagic cystitis
    • Adenovirus ? hemorrhagic cystitis
  760. Who is most affected by BK virus nephropathy
    • Transplant patients
    • Especially kidney and bone marrow transplant patients
  761. Who is most affected by adenovirus hemorrhagic cystitis
    Young boys that go swimming
  762. What is the clinical presentation of PML caused by JC virus?
    • Weakness
    • Visual changes
    • Difficulty with speech
    • Gets worse over time
  763. What is the clinical presentation of nephropathy caused by BK virus?
    • Fever
    • Gross hematuria
  764. What kind of viruses are paramyxoviruses?
    Enveloped negative sense RNA viruses
  765. Where do paramyxoviruses replicate
    Cytoplasm
  766. What is the only RNA virus that does not replicate in the cytoplasm?
    Orthomyxovirus ? in the nucleus
  767. How are paramyxoviruses transmitted
    Respiratory droplets
  768. What virulence factors can paramyxoviruses have
    • Hemagglutinin
    • Neuraminidase
    • Fusion protein
  769. What does hemagglutinin do
    • Binds to sialic acid in membranes of upper respiratory cells and red blood cells
    • Determines which cells the viruses can bind to
  770. what is the function of neuraminidase?
    cleaves sialic acid to release the newly formed virions from host cell
  771. What does fusions protein do?
    Plays a role in formation of syncytia = multinucleated giant cells
  772. What is syncytia
    Multinucleated giant cells
  773. What viruses are in the paramyxovirus family
    • Measles virus
    • Mumps virus
    • Respiratory Syncytial Virus (RSV)
    • Parainfluenza virus
  774. What kind of virus is measles virus?
    Enveloped negative sense RNA virus
  775. What family does measles virus belong to?
    Paramyxoviruses
  776. How is measles virus transmitted?
    Respiratory droplets
  777. What does measles virus cause?
    Measles = rubeola
  778. What is rubeola
    Measles caused by measles virus
  779. What are 3 childhood rashes
    • Rubella
    • Roseola ? HHV6
    • Rubeola ? measles
  780. What is the clinical presentation of measles virus?
    • 4Cs ? Cough, Coryza, Conjunctivitis, Koplik spots
    • High fever (>40oC)
    • Itchy maculopapular rash
  781. What are the prodromal symptoms of measles virus?
    • 4Cs
    • Cough
    • Coryza = runny nose
    • Conjunctivitis
    • Koplik spots ? small bluish white spots on red background found on buccal mucosa
  782. What is coryza
    Runny nose caused by inflammation of the upper airway
  783. What are kaplik spots
    • Pathoneumonic for measles
    • Small bluish white spots on red erythematous base found in buccal mucosa near 2nd molars
  784. What does the progression of measles look like?
    • Prodromal phase ? 4 days
    • Maculopapular rash 1-2 days after appearance of koplik spots
    • Rash starts at back of ears and spreads to head and neck then travels down to the rest of the body
  785. How do we differentiate measles from rubella?
    • Itchy maculopapular rash is confluent ? measles
    • Maculopapular rash is not confluent ? rubella
    • Both rashes start at the face and spread down
  786. What does confluent rash caused by measles look like?
    Starts as individual spots that join together to cover large surface
  787. What are the possible complications of measles virus?
    • Bacterial or viral pneumonia
    • Subacute sclerosing pan encephalitis (SSPE)
  788. What is SSPE
    • Subacute sclerosing pan encephalitis caused as a by persistent measles virus infection
    • Inflammation and sclerosing of the brain
  789. What causes subacute sclerosing pan encephalitis
    Persistent measles infection
  790. What is the clinical presentation of subacute sclerosing pan encephalitis?
    • Occurs 5-15 years after initial infection
    • Personality changes
    • Seizures
    • Myoclonus
    • Ataxia
    • Coma
    • Death
  791. How do you diagnose subacute sclerosing pan encephalitis?
    Anti-measles antibodies in the CSF
  792. How do you treat subacute sclerosing pan encephalitis?
    No treatment
  793. What virulence factors does measles virus have
    • Hemagglutinin
    • Fusion protein
    • NO neuraminidase
  794. What are Warthin finkeldey cells
    • Syncytial multinucleated giant cells found in measles infection
    • Also have characteristic cytoplasmic and intranuclear eosinophilic inclusion bodies
  795. Where are Warthin finkeldey cells found
    Lymphoid tissue
  796. How do we diagnose measles virus infection?
    • Symptomology
    • Presence of Warthin finkeldey cells
  797. How do we treat measles caused by measles virus?
    • Vitamin A reduces complications and mortality of measles
    • MMR vaccine = Measles, Mumps and Rubella
  798. What kind of vaccine is the MMR vaccine?
    Live attenuated vaccine
  799. Who is the MMR vaccine contraindicated in and why?
    Pregnant women ? live attenuated organisms can pass through placenta to infect fetus
  800. What kind of virus is mumps virus?
    Enveloped negative sense RNA virus
  801. What family does mumps virus belong to?
    Paramyxoviruses
  802. How is mumps virus transmitted?
    Respiratory droplets
  803. What does mumps virus cause?
    • Parotitis ? inflammation of parotic glands
    • Orchitis ? inflammation of the epididymis of the testis
  804. Where does mumps replicate
    Parotic salivary glands in the cytoplasm
  805. What are the major complications of mumps virus infection?
    • Orchitis
    • Meningitis
  806. What is orchitis
    Inflammation of the epididymis
  807. Who is affected by orchitis caused by mumps infection
    Adult men or teenage boys
  808. What is the clinical presentation of orchitis caused by mumps virus?
    • Testicular atrophy
    • Impaired fertility
    • Usually unilateral but Can be bilateral ? sterility
  809. How do we treat mumps infection?
    MMR vaccine ? measles mumps and rubella
  810. What virulence factors does mumps virus have
    • Hemagglutinin
    • Neuraminidase
    • Fusion protein
  811. What is RSV
    Respiratory Syncytial Virus
  812. What kind of virus is respiratory syncytial virus?
    Enveloped negative sense RNA virus
  813. What family does syncytial respiratory virus belong to
    Paramyxoviruses
  814. How is respiratory syncytial virus transmitted
    Respiratory droplets
  815. What does respiratory syncytial virus cause
    • Bronchiolitis
    • Pneumonia
    • Rhinitis
    • Pharyngitis
  816. Who is affected by respiratory syncytial virus infection
    Infants less than 6 months of age
  817. How does the respiratory syncytial virus infect cells?
    Attaches to the respiratory endothelium through G protein
  818. What is the most common cause of pneumonia in infants?
    Respiratory syncytial virus
  819. What is the most common cause of bronchiolitis in infants?
    Respiratory syncytial virus
  820. What virulence factors does respiratory syncytial virus have
    • Fusion protein
    • NO hemagglutinin of Neuraminidases
  821. How do we treat respiratory syncytial virus?
    • Ribavirin in adults
    • Palivizumab in high risk children (premature babies)
  822. What is Ribavirin
    • Nucleoside analogue
    • Used to treat hepC and RSV in adults
  823. What is Palivizumab
    • Monoclonal antibody against respiratory syncytial virus fusion protein
    • Used to treat RSV in high risk children (premature babies)
  824. what kind of virus is parainfluenza virus?
    Enveloped negative strand RNA viruses
  825. What family does parainfluenza virus belong to?
    Paramyxoviruses
  826. How is parainfluenza virus transmitted?
    Respiratory droplets
  827. What does parainfluenza virus cause?
    • Croup in children
    • Sever cold in adults
  828. What is croup
    Laryngotrachobronchitis caused by parainfluenza virus
  829. who is affected by croup caused by parainfluenza virus
    children
  830. What is the clinical presentation of croup caused by parainfluenza virus?
    • Seal bark cough in inspiratory stridor
    • Steeple sign on X ray = narrowing of subglottic region
  831. What virulence factors does parainfluenza virus have
    • Hemagglutinin
    • Neuraminidase
    • Fusion protein

Card Set Information

Author:
Marine
ID:
327613
Filename:
Flashcards Virology
Updated:
2017-01-23 10:03:22
Tags:
micro
Folders:
Micro
Description:
Virology missing Lysssavirus Rotavirus Tick born encephalitis
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