Animal Viruses

Parvovirus

dependovirus

ssDNA icosahedral; naked

Coinfects with adenovirus

highly immunogenic due to exposure many times

papillomavirus

polyomavirus

SV-40 virus

ds circular DNA; icosaheral; naked

• causes CIN (cervical intraepithelial neoplasia)
• 34 varieties/ serotypes

wart/ chancres; domelike structures taht affect growth of epithelium; can be cross-linked; can coalesce and cause larger legions; cream-looking= large and unusual areas in AIDS case; flat warts are classic for kids

specific for what they cause (ex: if genital warts, only in the genital area)

no coinfectivity

• warts (such as small genital warts)
• virus is only released when the warts break open
• flat lesions
• AIDS complicates the warts

• one to four
• I: minimal dysplasia; abnormal growth in spot of cervical growth
• II: moderate abnormal growth
• III: severe dysplasia or carcinoma in situ; severe/ tumor at site
• IV: severe dysplasia and carcinoma in situ

usually mitosis is not visible in tissues. However, mitosis is visible in a section of epithelium in dysplasia; mitotic bodies

abnormal cells not functioning properly

dsDNA; icosahedral; naked

adenovirus

Serotype A: no human disease/ highly immunogenic

Serotype B: not highly immunogenic; acute respitatory disease; pharyngitis; epidemic keratoconjunctivitis; acute hemorrhagic cystitis

adenovirus has giant spike proteins that allow entry

10% of all immunity in our body is directed twoards this type

• severe resp disease
• takes a while for monocytes to recruit helper B cells
• T cells take a while; doesn't start up interferon cascade
• Dependovirs (and Badenovirus)  can coinfect with this

infection of the kidneys

HBV

dsDNA; icosahedral; naked

• acute and chronic hepatitis
• hepatocellular carcinoma
• glomerulonephritis
• immune complex disease
• causes a disease of gamma globulin (gammopathy)

• the most common liver infection
• transmitted through blood and body fluid contact (direct contact with fluids, unprotected sex, unsterile needles, mother to newborn)

released into all body fluids via direct inoculation into discontinuous epithelium or into an individual

• jaundice (autoimmune reaction where some hepatocytes are damaged; overload of bile; staining body cavities and swollen stomach)
• nausea and vomiting
• swollen stomach

most healthy adults (90%) who are infected with the hep B virus will recover and develop protective antibodies against future hep B infections

the opposite is true for children and adults; long incubation period and infected persons are able to pass the virus to others at this stage; bulk of kids get chronic

a person who has positive surface antibodies (HBsAg or anti-HBs) has recovered and is no longer contagious to others

If a person tests positive for the virus (HBsAg) for more than six months, they are chronically infected

Increased risk for cirrhosis (immune system destroys liver--> mush) and liver cancer

• one caused by liver damage
• one caused by liver starting up (when born)

100s exist; all species specific



Treatment can get rid of it. For people who are asymptomatic or don't get treated, they get serious issues--> hepatocellular carcinoma or liver can turn into jelly (glomerulonephritis)

only affects humans; for other animals, there are hep B for them

dsDNA; icosahedral; enveloped

• Herpes simplex (HSV-1; cold sores)
• Herpes simplex (HSV-2; genital herpes)
• Cytomegalovirus (CMV)
• Epstein-Barr virus (EBV)--> infectious mononucleosis; Burkitt's lymphoma; nasopharyngeal carcinoma
• Varicella-Zoster virus (VZV)
• Marek's Disease virus

over 90% of world is naturally infected by them; established long term latency in individual who is infected; stress reactivates them

direct inoculation from infected to non-infected individuals

most cause relatively harmless disease (not mortality)

• fever blisters or bump in mouth where gum reaches gumline
• most likely inoculated by relative
• rarely activates before 12
• back in CNS after activation
• cold sore
• > 90% of the world gest HSV-1
• viral reactivation during stress

• Whitlows can form: reinfection at site distal to lesions; non-oral presentation
• when it occurs in kids below twelve, they get eczema herpeticum

• Genital herpes (STD)
• pustule like lesions similar to those in HSV-1
• reactivation at times of stress (3-6 lesions)
• microchancres (so small; can invade other places)--> makes person slightly infective

mom with herpes simplex 2 can cause her child to get ocular HSV-2 or get eczema herpeticum at birth, leading to sloughing off of skin

• most frequently transmitted to a developing child before birth
• symptoms may range from moderate enlargement of the liver and spleen, loss of vision, mental retardation to fatal illness
• major cause of disease and death in immunocompromised patients, including organ transplant recipients, hemodialysis patients, cancer patients, immunosuppressive drug patients, and HIV patients; pneumonia, retinitis, and gastrointestinal disease are the common manifestations of disease

• cells of immune system and nerves/ neural tissue
• CMV +
• teratogenic effects; low brain weight, etc.

• infectious mononucleosis
• Burkitt's lymphoma
• Nasopharyngeal carcinoma
• chronic fatigue syndrome

**resolves within three months; some get 8 months)

likes cells of epithelial origin and lymphocytes

release of cytokines --> extended chronic fatigue

myalgias/ short-term arthritic syndrome

• in two-three weeks, look at the blood (lymphocytes get huge vacuoles as they release lots of viruses)
• some get chronic fatigue

• fatigue
• malaise
• loss of appetite
• headache

photophobia

reddening, swelling, white patches

• cough
• spleen enlargement and ab pain

• nausea
• chills, fevers, aches
• soreness, reddening

• extra depositions of lymphatic tissue
• lymphocytes in areas that they should not be in
• functionally inactive
• fills up circulatory system with junk

two forms: sporadic (outside of Africa) and endemic (infections occurring in Africa)

symptom: enlargement of tissues of oral cavity

• the cancer grows into the sinuses or around the eye, cheek bone, cranial nerve, and hypopharynx
• tumor of epithelial cells in oral or nasal tract
• deformation of jaw/ nose as it metastasizes

I and II: tumor and damage small--> hard to detect

• III: growth  into sinueses/ infarct sinuses
• IV: eye involved; massive changes in sinuses and ears; metastasizes up cranial nerves

• chicken pox
• shingles

• ***virus can live 72 hours in adverse environment***
• ***virus gets in through discontnuous epithelium and sets up latency in trigeminal ganglion

• - chicken pox
• - pock marks cause discomfort (display nerves/ not much bleeding); filled with liquid, pus leaks out
• immunity builds from it; not much secondary or chronic

if over 18: shingles--trigeminal ganglion; sets up shop there

• Zoster presentation
• virus follows cranial nerves in variety of fashion
• body has a midline; people can get bilateral or unidirection
• extremely painful; nerves

Neurolymphomatosis causes asymmetric paralysis of one or more limbs. Difficulty breathing or dilation of the crop may occur. Lymphomatous infiltration/tumors in the skin, skeletal muscle, visceral organs.

Acute Marek's disease is an epidemic in a previously uninfected or unvaccinated flock, causing depression, paralysis, and death in a large number of birds (up to 80 percent). The age of onset is much earlier than the classic form; birds are four to eight weeks old when affected. Infiltration into multiple organs/tissue is observed.

Ocular lymphomatosis causes lymphocyte infiltration of the iris, turning it gray, unequal size of the pupils, and blindness.

• dsDNA
• complex capsid
• complex e/n

vaccinia and variola

cow pox; causes lesions on hands; shares similarities to variola

contract cowpow--> immune to smallpox.

• smallpox; first disease targeted for eradication by WHO (1920-1930)
• we are the only species that variola can infect
• incubation time: 4 days--> fever--> pox--> 5-6 days: fevers 105 degrees

• can bleed into themselves; coalesce to form larger entities
• kidneys, liver, etc. Organ dysfunction because its too hot

formation of papules adn them pustules. Day 6-7 is the fever peak

hypopigmentation of scars

ss+ RNA; icosahedral; naked

• poliovirus
• enteric cytopathogenic human orphan (ECHO)
• coxsackie viruses
• rhinovirus
• HAV

• tiny viruses
• ability to survive outside host

• polio can freeze 
• Hep A: can hold for 24 hours in bad situations

• targeted by WHO
• cutter vaccine

contaminated drinking water or through contact with contaminated surfaces; oral caity entry

• after passing through the stomach, the virus (capsid) establishes itself in the intestinal lining
• here the virus replicates and enters the bloodstream through the immune system
• once in the blood, it gains access to the nervous system, where the destruction of motor neurons results in paralysis

it undergoes transcytosis (goes in one side and out the other)

• infects Schwann cells and nerves
• causes paralysis, which also affects muscles adn leads to iron lung usage

• asy: 90-95%
• mino illness: 4-8%
• non-paralytic: 1-2%
• paralysis: 0.1-1%/ spinal polio: 79% of paralysis; bulbospinal: 19% of paralysis; bulbar: 2% of paralysis

• cold
• respiratory tract; mucous; only infections you're releasing to the environment

the virus can survive in bizarre environments, such as high heat, salt, etc. 

inflamation of liver, sweling of gut, jaundice; gas is secondary to fermentation

about 90%--> short-lived disease (3 months)

up to 24 day incubation period

people over age 9-10

• opposite true for kids due to function of liver
• high prevalence in Africa and Central America

• •Jaundice by age group:
• –<6 yrs     <10%
• –6-14 yrs   40%-50%
• –>14 yrs    70%-80%
• •Rare complications
• –Fulminant hepatitis
• –Cholestatic hepatitis
• –Relapsing hepatitis
• •Incubation period
• –Average 30 days
• –Range 15-50 days
• •No Chronic sequelae

ss+RNA; icosahedral; naked

Norwalk virus (gastroenteritis)

gastroenteritis; outbreak in 24-48 hours

CLASSIC PRESENTATION: acute-onset vomiting, watery non-bloody diarrhea, abdominal cramps and nausea

• dehydration is the most common complication
• recovery is generally complete
• 'secondary renal dysfunction
• 10 day infection

no great immunity against them

• hardy outside the body (72 hours)
• small dose needed

dsRNA icosahedral naked

• orthoreovirus
• rotavirus
• orbivirus
• aquareovirus
• coltivirus (CO tick fever)

• fecaloral route
• disease can be fatal in infants (causes pediatric diarrhea-- #1 cause)

mild to severe disease in adults

spread as kids slobber over each other and contaminate surfaces

2-3 days infection with severe diaarrhea; body weight drops 10-15%

• RNA icosahedral enveloped ss+ 
• Rubella (German measles)

GERMAN MEASLES

• spread by respiratory droplets
• incubation 12-24 days
• generalized lymphadenopathy (swollen hot lymph nodes)
• diffuse, pink macular rash
• postnatal rubella arthritis
• little petechia and fever are problems
• affects interleukins from patients

ss+ RNA icosahedral enveloped 

• yellow fever
• Hep C Virus

• in africa and south america
• mosquitos trannsmit
• flu-like symdrome--> severe hepatitis-->hemorrhagic fever

• virus in salivary glands
• 75-80% get flu-like syndrome
• 20% get hemmorhagi fever--> die due to internal injuries

remainder get hep

• blood-borne
• inflammation of liver; chronic liver disease
• sets up latency (long term effects)

most common extrahepatic symptom is arthritis and crystallizaiton in joints

fatal in 3% of cases

ss+ RNA, helical, enveloped

Corona/ SARS/ MERS

resp tract disease causing distress and collapse due to gene alteration in cells in lungs

no gas exchange

can be aerosolized; do well in ventilation

ss+ RNA; helical; enveloped

• Rous Sarcoma Virus
• Feline leukemia virus
• Simian immunodeficiency virus
• HIV-1 and -2
• Human T-cell lymphoma virus (HTLV-1,2,3,4)

• all have an enzyme that is family of reverse transcriptase
• all set up latency for as long as they can (usually in immune system--> dysfunction)
• all can be complicated by other pathogens

oncogenic virus; systemic tumors of soft tissue origin; in chicken feces

• acquires it as a little kitten; they get leukemia; affects IS
• the cells look like themselves, but don't function like it

• primate cousin of HIV
• blood borne pathogen
• evolutionary pressure

• latency is realyl short
• clinical phase is short
• death is rapid

attacks CD4 helper T cell lymphocytes and other CD4 cells

• macrophages migrate into tissues. Gp120 is the glycoprotein that is expressed. 
• This sets off CD8 and lymphocytes, which require CD4 for activation. 

- the virus infects by binding of the virus to the CD4+ immune cells, first macrophages then lymphocytes (helper T-cells)

the glycoprotein 120 is expessed on those cells

the viral replication adn gene expression help induce cytopathologic effects in the CD4+ cells

CD8+ cells require CD4+ cells for activation

CD4/CD8 ratio

virus remains latent for up to 12 years

initial disease progression is a slight lowering of the CD4/CD8 ratio

AIDS

blood: sexual or clinical contact, transfusion, needle stick

Serum: clinical contact, needle stick

• •Thrush/ Candidiasis
• •Pnuemicystis pneumonia
• •Herpes virus complications (all members)
• •HPV complications
• •Kaposi’s sarcoma
• •Cryptococcus infections

affects lymphocytes and CD8 cells

• establishes latency, no complication until activation, when rapid production of T cells takes place
• they look like T cells but don't function like them (don't kill things)

they overcrowd the lymphatic tissues, leading to physiological dysfunction

Flu: acute respiratory distress; neuaminidase; hemaglutinin

ss- RNA helical enveloped

• acute respiratory distress
• nueraminidase
• hemaglutinin

• they have two key spike proteins: -neuraminidase: allows cleavage-hemaglutinin: allows association with the respiratory tract epithelium and RBC when systemic to avoid teh immune system can species jump
• mosaic viruses can form (viruses with he

antigenic shift: development of hybrd viruses using different strands of H and N combos; massive number of new cases

antigenic drift: partial immunit against one but not both; can be both; not many new cases)

causes endemics (slight change) or pandemics (big changes)

mutates and host jumps

ss- RNA helical enveloped

• Rubeola (measles)
• Mumps virus
• Respiratory syncytial virus (RSV)
• Canine distemper virus

Humans are the only host

incubation: 10-14 days

early stages include broncioloitis

buccal "Koplik spots"

rash first appears around the temples

High fever with capillary leakage

• bad; splotchy rash; really high fever
• finestra (wndows between cells that let fluid and immune components go in and out resp system); fever with capillary leakage

they open to largest capacity and allow fluid loss to circulatory system, leading to thicker viscosity of blood, heart pumps harder, pressure increases, chainge in body chemistry, and maybe kidney failure

parotid lymphadenopathy

• causes bullneck
• high rever

1% of people get complications in this order:

• 1) deafness
• 2) pancreatitis (damage to cells that are insulin responsive and parenchyma)
• 3) meningitis
• 4) orchitis (inflammation of testicles)

highly contagious

• RNA 
• helical 
• enveloped
• ss-

Rabies

neural dissemination

glands of head and neck

not foam but salivary glands that pump out a lot of salt and protein

causes neurological problems: parkinsonian/ alzheimer like issues( some parts of CNS gone and replaced with microcysts)

people lost memory/ dementia

attacks control areas

virus itself is shed into salivary secretions; has to be deep wound inoculation; adn 70-100 capsids must be injected

ebola hemorrhagic fever

Marburg

• viral
• hemmorhagic fever
• sudan, bundibugyo, and zaire ebola: can infect humans and primates

Reston ebola can't infect humans; tries to, but it can't get in

• one person survived
• viral hemmorhagic fever
• biowarfare agent
• higher fever
• onset of bleeding is earlier