mb exam #4

fungi

Yeasts and Molds

• unicellular (single, oval or spherical fungal cell)
• "bacteria-like" in appearance

asexually by budding

• 1. Division of nucleus
• 2. Passage of one nucleus to a bud that "balloons out" from the wall of the mother cell
• 3. Formation of wall between the bud and mother cell
• 4.Daughter cell – bud or blastospore
• 5. Daughter cell initially smaller, increases in size and produces own buds

filamentous (multicellular) filamentous or tubular structures.

asexually

• 1.Germination of condium (reproductive element) – sends out a filament that grows by elongation at its tip
• 2. Hyphae – elongated filament
• 3. Mycelium – multiple branches of hyphae
• 4. Many nuclei within each hyphae
• 5.Formation of septae – "crosswalls" within hyphae
• 6.Conidia – terminal end of hyphae – "seeds" for new colonies

enlongated filament

multiple branches of hyphae

many

"crosswalls" within hyphae

Terminal end of hyphae - "seeds: for new colonies

two reproductive bodies connect and haploid cells fuse to form diploid cells (spores)

the property of having two morphological shapes

yeast

mold or mycelial

size, presence of capsule, cell wall thickness, spores or conidia production

molds

yeasts

4 -> 6

• Sabouraud's Dextrose Agar (SDA)
• Dermatophyte Test Media (DTM)
• Nigerseed (birdseed) agar

corn meal agar (spore formation)

undisturbed growth

(dry, cotton-like, masses)

(moist, opaque, creamy colonies)

"Surface infections"

fungal infections of keratinous structures

infections penetrate beneath the skin and involve that subcutaneous connective and bone tissues

infections of internal organs

infections in compromised or immunosuppressed

hair or skin

lesion appearance - scaly or pigmented area of the skin, or nodules on shaft of hair

good hygiene

dermatomycoses (cutaneous mycoses)

fungi that invade keratinized and cutaneous areas of the body (nails, hair and skin)

• Microsporum
• Trichophyton– T. rubrum
• Epidermophyton

• 1. Hyphae of dermatophytes grows into keratinized tissue
• 2.Growth outward from infection site in concentric circles
• 3. Enzyme production – keritinase, elastase and collagenase

• Tinea Capitis (ringworm of the scalp)
• Tinea Barbae (ringworm of the beard)
• Tinea Pedis (ringworm of the foot)
• Tinea Curis (ringworm of the groin)
• Tinea Corpis (Ringworn of the body)
• Tinea unuium (ringworm of the nails)

inflammation and itching of scalp

• hyphae spread into keratinized areas of scalp and hair follicle
• fungal growth weakens hair
• breakage at shaft
• alopecia (hair loss) which is localized and spotty

(hair loss) which is localized and spotty

bearded areas

scaly lesions

developement of deep pustules

permnanent hair loss

foot lesions "athletes foot"

• growth between toes of small fluid filled vesicles
• vesicles rupture
• development of shallow lesions that itch

public showers, swimming pools, failure to dry between toes.

• lesions in groin or perianal area
• Red, scaly, itchy and dry "jock itch"

moisture in groin area, wet bathing suits, athletic suporters, tight-fitting slacks, pantyhose and obesity

non-hairy areas of the body

lesions are reddened, scaly with papular eruptions

fingernails and toenails

superficial thie pathced nail bed

thickening of nail, accumulation of cheesy debris, cracking and discoloration of nail

Microscopic ID : (tissue scrapings) + (10% KOH or 10% NaOH) + heat -> (frees hyphae from keratinous material) + stain (gram stain, wright stain or periodic acid - schiff) -> Presence of septate hyphae

Macroscopic ID: Cultures on (Dermatophyte Test Media (DTM) or Sabouraud's Dextrose Agar) for about 1 to 2 weeks in room temperature -> funal colonies

• nonprescription – salves/ointments contain tolnaflate; symptomatic relief
• good hygiene
• oral antibiotic therapy – griseofulvin (accumulates in keratin tissue)
• topical antifungal agents – Azoles (ketoconazole, miconazole and itraconazole)

Subcutaneous Mycoses

normal inhabitants of soil or organic matter

wounds or abrasions of skin

rose gardner's disaease

sporothrix schenckii

• traumatic implantation of fungus into skin
• painless papule at inoculation site
• enlarge to form an ulcerated lesion

spread of cutaneous infection to regional lymph nodes

• fungus forms multiple nodules after being spread by draining lymph channels
• nodules may ulcerate
• untreated lesions last years

horticulturists, foresters, gardeners, farmers and basket weavers

• A direct culture is taken from lesion exudate
• Yeast (37 C) - oval, cigar shaped
• Mycelial phase (25 C) - brown/black colonies; conidia - flower-like clusters

• potassium iodide orally in juice or milk
• potassium iodide – topical application on open lesions
• fungus cannot withstand heat – heat packs

antibiotic of choice – amphotericin B

true pathogens

• inhalation of dried yeast cells
• colonize lower respiratory tract
• asymptomatic or primary pulmonary infection (PPI) that parallels TB
• disseminated to other organs due to compromised defense mechanisms

cryptococcosis

Cryptococcus neoformans

soil, high association with pigeon droppings

Lung (PPI)

disseminated sites - (brain, meninges, CNS and mucicutaneous systems)

fever, cough, nodules of lung

arise dues to tumor-like masses at secondary sites, headaches, mental changes, coma, parlysis, eye disturbances and seizures.

• Occupational risk - (outbreaks associated with workers demolishing buildings where pigeons have roosted)
• AIDS patients - highest case rate U.S - chronic meningitis (most common)

The presence of the capsule

• India Ink Preparation
• Quelling Reaction
• Sabouraud Agar
• Latex Agglutination Test

wide, clear capsular halo

capsular swelling

slimy, mucoid colony

presence of crptococcal capsular polysaccharide

pigmentation

amphotericin B and fluconazole

normal flora

respiratory tract, mouth, intestinal tract and vagina

• overgrowth of normal flora
• inflammation of epithelial surfaces (most frequently oral cavity and vagina)
• dissemination
• infectivity of internal organs

Candidiasis infections

cutaneous infections and disseminated infections

Candida albicans

• Thrush or oral candidiasis
• Vaginal candidiasis (VC)
• Esophageal candidiasis
• General candidiasis

• due to host's conditions.
• diabetes, natural immunological deficiencies, or exposure of skin to moist environment

• adherence of blastoconidia to epithelial surfaces
• fungal proliferation
• invasion of epithelial tissue

Thrush or Oral Candidiasis

white, adherent patches (pseudomembranes) attach to the epithelial membranes of the tongue, gums, cheeks or throat

fungal mat

yeast, hyphae and epithelial debris

newborns

mother -> child

Vaginal candidiasis (VC)

yellow to white milky discharge, inflammation, painful ulcerations and itching

an increased glucose content of vaginal secretions

diabetic women, pregnant women and broad spectrum of antibiotic therapy users

complication of AIDS patients

painful bleeding, ulcerations, nausea and vomiting

infections of epidermal tissue

• folds of skin on obese people (usual sites – upper legs or underarms)
• tissue that remains wet (occupation –dishwasher)
• skin covered by wet diapers (diaper rash)

• cutaneous infection
• Iatrogenic infections

a multi-system disease

(produced by physicians) – usage of catheters or prosthetic devices

• microscopic examination : gram stain the lesions or exudates. (gram positive = budding yeasts cells)
• Macroscopic examination: cultures on SDA– (white to cream colored colony, pasty with a yeasty odor) // clutures on corn meal agar – (chlamydospore formation)
• Germ tube test : yeast cells + serum + (incubation for 2-4 hours) = germ tube formation

• cutaneous - imidazoles
• disseminated - amphotericin B

hetergeneous in size

intracellular

living cells

the cytoplasm or the nucelus of infectedells.

• RNA
• DNA
• protein synthesizing processes

either RNA or DNA (NOT BOTH)

have to enter the host and replicate in particular cells or organs.

study of how viruses cause disease in their target hostsusually carried out at the molecular or cellular level.

viruses must enter a host, come in contact with susceptible cells, replicate and produce cell injury or cell death.

• Fecal-oral route
• respiratory route
• arthropod-borne route
• sexually transmitted route

contaminated food or water

through the air

bite of insects or animals

unprotected sex

poliovirus, rotavirus, hepatits A virus

influenza viruses, parainfluenza viruses, measles virus, mumps virus, respiratory syncytial virus

encephalitis viruses, rabies virus

herpes viruses, haptatitis B, C and D viruses, HIV

DNA/RNA

The protein shell that surrounds the genome

the structure of the genome AND the capsid

false, only some

enzymes associated with its genome

envelope

viral glycoproteins and lipid bilayer derived from the membrane of the infected cell

peplomers

glycoproteins in the form of spikes in the envelope

attach to the host cell receptor

The complete, infectious virus particle

structural subunits of the capsid

the organization of the genome :

• RNA or DNA
• Single or double strandedness
• Manner in which the genome is expressed after uncoating in cyotplasm or infected cell.

1. After uncoating in the infected cell



2. Synthesis of virus-specific mRNAs that

• are translated
• into virus-specific

• protein(s). Use
• virus-specific enzymes

• or host enzymes
• for this process

3. All viruses use host protein synthesizing machinery to make virus-specific protein(s).

synthesis of virus-specific messenger (m) RNA molecules that are translated into virus-specific protein(s).

single stranded

1 or more segments

+ (mRNA) or - (Anti-mRNA)

polovivirus and hepatitis A virus

messenger-sense (+)

messenger RNA

proteins (polyproteins)

positive polarity

rabies virus

CANNOT

negative

virion-associated transcriptase (RNA dependent RNA polymerase)-transcribes the negative-sense (-) RNA genome into m(+)RNA molecules

The genome is class 3 has TWO identical positive (+) strands of RNA.

HIV

genomic RNA to DNA to mRNA

virus contains a virion-associated reverse transcri­ptase, which transcribes the genome (RNA) into a complementary (c) ds-DNA

• it is translocated to the nucleus and integrates with host
• genome (provirus).

provirus

a host cell DNA-dependent RNA polymerase in the nucleus of the infected cell (few exceptions).

Viruses with double-stranded (ds)-DNA

ds-DNA to mRNA (regulated) to viral proteins (classical pathway found in eukaryotic cells)

the nucleus

multiple cycles resulting in expression of alpha,beta and gamma genes

immediate early genes - trancsription regulatory genes

early genes - required for viral DNA syntheis

the late genes - transcribed after DNA synthesis and produce viral structural proteins

herpesvirus

viruses with partially ds-DNA

double stranded

dsDNA

virion-associated DNA polymerase

(i)mRNA that is translated to produce viral proteins and (ii) genomic length RNA that serves as a template for the synthesis of genomic DNA by a virion-encoded .RNA dependent DNA polymerase (RT)

hepatitis B virus

Genomic DNA to RNA to Genomic DNA

virion genome is converted to complete ds-DNA by virion associated DNA polymerase

HOST RNA polymerase

(i) mRNA’s and (ii) genomic length (+) RNA

virion-encoded reverse transcriptase (RT)

No

• adsorption
• entry into cell
• uncoating
• synthesis of viral proteins
• replication of viral genome
• morphogenesis
• release

virion attach to an appropriate cell via virus-specific receptor

non-enveloped viruses: receptor-mediatedendocytosis envelopedviruses: fusion of viral envelopewith host cell membrane

removal of capsidproteins in non-enveloped viruses (genome is free in the cytoplasm of cell) or release of nucleocapsid in cytoplasm (enveloped viruses)

Expression of virus genome: RNA and DNAviruses have different strategies

different strategies, depending on the nature of the genome(RNA or DNA).

assembly of progeny virions in thecytoplasm (poliovirus) or in the nucleus of the infected cell (herpes virus) - depends on the virus and cell involved.

progeny virions (newly synthesized) arereleased from infected cells by cell lysis (lytic cycle) or by the process of budding from the host cell membrane (enveloped viruses).

65 million people

33-36 million

over 16 million

15,000

1.5 million

• 70% - men
• 30% - women

121,000

three

10/100,000

theory that simian immunodeficiency virus crossed into humans early 1900s

Haiti in 1969

identical strands of RNA

host cell nucleus

anti-HIV

• Homosexual and bisexual men
• Intravenous drug users
• Children born to mothers who are HIV+
• Hemophiliacs (blood product recipients)

Genome (two identical strands of RNA)

• reverse transcriptase
• integrase
• protease

RNA dependent DNA polymerase

intergrates DNA into host chromosome

cleaves certain certain proteins during replication

• GP41
• GP120
• GP160

stalk for GP120

site of attachment to host cell receptors

combination of GP41 and GP120

CD4 receptors

• T cells
• from bone marrow and the thymus

• T cells
• Macrophages
• Monocytes
• Dendritic Cells in lymphocytes
• Microglial cells in brain

RNA -> DNA -> mRNA

within hours of virus entering the system

because it brings it's own enzymes

provirus

HIV undergoes rapid genetic changes

• attachment of GP120 to host cell CD4 receptor
• fusion - viral envelope and host cell plasma membrane fuse together and release viral core into cytoplasm
• virion -associated reverse transcriptase synthesizes a complementary double stranded DNA
• Complemenetary DNA is intergrated into host chromosome (provirus) by integrase
• The provirus is transcribed to produce genomic RNA (genome) and mRNA (viral proteins)
• Assembly of new viruses occurs in the cytoplasm
• Viruses are released by budding - acquires envelope and GP120

the destruction of immune system cells

a secondary or opportunistic infection

• age
• host cell environment
• treatment
• nutrition
• viral strain
• tuberculosis (enhances pathogenesis)

4

Acute or primary HIV disease stage

asymptomatic HIV disease stage

Chronic symptomatic HIV disease stage

Crisis stage of AIDS

Stage 1

2-8

2-4 weeks

mononucleosis

fever, sweat, lethargy, headache, diarrhea

there are high levels of the virus

"window of infectivity before sensitization"

The body has not had enought ime to produce an immune response by cells are making more viruses

negative

Asymptomatic HIV disease stage

anywhere from months to 11 years

antibodies against HIV

antibodies

stage 2

the virus

chronic symptomatic HIV disease stage

for months or years

T4 cells

200

3

high levels of virus in blood which can infect more host cells

fever, weight loss, malaise, fatigue, night sweats, headaches, and swollen lymph glands

the loss of immune response and the onset of opportunsitic infections and cancer

Crisis stage or AIDS

opportunistic infections and cancer

stage 4

cryptosporidium, toxoplasma, pneumocystis, mycobacterium, cytomegalovirus, epstein-Barr virus, herpes simplex virus, kapsi's sarcoma

communicable

all of them

first and third stages

blood transfusions

infected mother to newborn

35%

Giving an antiviral

6%

18%

Anti-retroviral therapy

cleansing the body of HIV

all cells containing the provirus while eliminating any viruses from the body

the rate of mutation of HIV

• Reverse transcriptase inhibiotors
• protease inhibitors
• CCR5 antagonist
• Integrase inhibitors
• Fusion inhibitors

• Nucleoside analogs
• Non-Nucleoside compounds

AZT, tenofovir, emtricitabine

nevirapine, delavirdine, efavirenz

saquinavir, ritonair, indinavir

block receptor which inhibits viral attachment

prevent intergration would give a better chance to eliminate virus (if it is extracellular)

• "AIDS" cocktails
• Highly active anti-retroviral treatment (HAART)

use of triple combination therapy

expensive

"reservoirs or dormant HIV"

miltefosine and perifosine

(enzyme-linked immunosorbent assay)

antibodies

• Ora Quick rapid HIV-1 antibody test
• Uni-gold recombigen HIV

a second time six months later then a confirmatory test is performed.

Western blot

Several virus-specific proteins

Non-segmented single stranded RNA

present

on the same glycoprotein

parainfluenze, RSV, Measles, Mumps

Segmented single stranded

present

on seperate glycoproteins

influenza

upper and lower respiratory tract infections

10-15%

4

1,2 and 3

3

respiratory route (inhalation of droplets)

in the respiratory tract

no

croup

• characteristic spasmodic cough
• difficulty breathing
• rhinarrhea (runny-nose)

bronchiolitis and pneumonia

transient (short lived); reinfiection possible

detect viral antigens in cells from nasal secretions

no ant-viral drugs, only symptom management

no

1

infants and children

respiratory route

no

1-5 days

• bronchiolitis and pneumonia in infants less than 6mos old
• fever and cough
• rinorrhea

transient; reinfection possible

detect viral antigens in cells of nasal secretion

• Isolation of infected child
• antiviral drug, ribavirin, used if severely infected

• RSV immune globulin (synagis0 - short lived, given monthly
• palivizumab

no

1

childhood

subclinical

respiratory route

respiratory tract and lymph nodes

yes

12-21 days

• fever, headache, pain
• swelling of (one or both) parotid glands
• symptoms have sudden onset
• complications

• orchitis - swelling of testes (higher chance in adults)
• meningitis - CNS involement

• IgM antibodies present for a month after infection
• IgG antibodies not present during acute infection; present during convalescent stage and for life.

yes

Live, attenuated (non-virulent) vaccine - MMR (measles, mumps, rebeola)

• First at 12-15 mos old
• Second at 4-6 years or 11-12 yrs old

1

• acute febrile (fever)
• exanthmatous (rash)

yes, highly

• Humansa are the only natural host
• There is no carrier state

respiratory route

10-14 days

• The 3 C's : cough, coryza (head cold, rinorrhea), conjunctivitis (eye infection)
• koplik spots
• warthin-finkeldey
• viremia
• maculopapular rash

characteristic of measles; red/yellow spots with white ceter around molars in the mouth

as virus infects neighboring cells it causes them to fuse together resulting in giant, multinucleated cells, characteristics of measles

reddish rash on the hands and face which can spread to rest of body

permanent immunity, IgG antibodies persist for life

serodiagnosis (test for antibodies)

yes. MMR vaccine

3

A,B and C

only A and B

Pigs and birds

pigs

8

transcriptase that makes mRNA

2

• H or HA - hemagglutinatinin for attachment to cell receptor
• N or NA - neuraminidase for release from infected cells

host cell membrane

antigenic

make a new vaccine each year

by two mechanisms

minor antigenic shift

virion-associated transcriptase changes one or two nucleotides which slightly changes the antigenic properties of the peplomers

respiratory route

1-2 days

• abrupt onset of fever which lasts 3-4days
• severe headache
• myalgia (muscular aches)
• common complication - pneumonia

no permananet immunity

antigenic changes in the virus

serodiagnosis

• anti-influenza drugs :inhibit uncoating
• Neuraminidase inhibitors

• amantadine
• rimantadine

type A

anti-influenza drugs

• Relenza (zanamivir) - nasal spray
• Tamiflu (oseltamivir) - tablet

neuraminidase inhibitors

prevent the release of virus from infected cells, decreases the severity and duration of infection.

two subtypes of influenza A and one subtype of influenza B

to respond to antigenic changes of the virus

• Inactivated virus vaccine given to high risk groups
• live, attenuated intranasal vaccine (LIAV) given to healthy people (2-49yo)

elederly, people with immune, cardiovascular, pulmonary or metabolic disorders, infants, people on aspirin therapy or people with asthma.

lower temperatures

Upper respiratory Tract (URT)

• vaccine is grown in chicken eggs, so shouldnt be given to someone with allergies to eggs
• Vaccine should not be given to people who have a fever or those who are not fully healthy.

H of H1N1

N of H1N1

transcriptase subunit 1

transcriptase subunit 2

• subclinical or asymptomatic
• acute viral hepatitis A infection

subclinical/asymptomatic infection

subclincial or asymptomatic infection

50%

no

15- 50 days

• preicteric
• icteric

• virus is replicating in intesitnal cells;
• abrupt onset of fever
• fatigue
• anorexia (loss of appetite)

a few weeks to several years

• viremia - liver infected
• dark urine
• janduice

1-2 weeks

fully

fecal-oral route (contaminated food)

IgM and IgG antibodies are produced

a few months

entire lifetime

test for presence of IgM and HAV antibodies

passive and active immunization

human gamma globulins - give person specific antibodies for immediate but short lived protection

vaccines

• inactivated hepatitis A vaccine
• twinrix

used for children between 12 and 23 mos old, two doses spaced six months apart

combined hep A and hep B vaccine - used for persons 18 years and older.

The Dane particle

25

carriers of Hepatits B virus and have a higher risk of chronic liver disease.

• chronic hepatits
• cirrhosis
• primary hepatocellular carcinoma (HCC)

no

partially double stranded DNA with a virion-assoicated polymerease

envelope protein that is specific to Hepatits B virus

differentitate between hap A and hep B

asymptomatic

1-2 months

lifelong immunity

similar to HAV (have iteris and preucteric phases)

43-180 days

less than six months

HBV and HDV

fulminant hepatitis

sexual contact or by contaminated food

chronic carrier state

one of the common long term sequela (pathological condition resulting from disease) of acute hep B.

small

from infected mother to infants

carrier

IgG and HBsAg antibodies are produce and give lifelong immunity after infection

• perform a test to detect the presence of HBsAg (only indicates the presence of an infection, not the type)
• perform further tests, spaced 6 months apart to determine type

• Hepatitis B immunoglobulin (HBIG) - more selective, higher amount of antibodies for the virus
• standard immune serum globulin
• human gamma globulin

• Recombinant vaccines used for 0-18 year olds
• twinrix
• for infants born to HBsAg postive mothers

• recombivax HB
• energix-B

isolating the genes for antigen production and putting them into a yeast cell which can make the antigen thich is purified and used as a vaccine

recombivax HB

HCV

asymptomatic

the establishment of a persistent infection

high rate of chronic/persistent infection leading to hepatocellular carcinoma

viremia

slow

>10 years

>10 years

>29 years

parentally or by sexual contact

use antibody testing to detect the presence of HCV antigens (not type)

combined interferon-alpha2b and ribavirin

combination of two has a synergistic effect; used to reduce the level of virus which prevents or slows liver cirrhosis and HCC (cant completely remove virus)

Delta agent

RNA virus that cannot replicate itself

requires the presence of HBV for replication and trasmission

plant viruses (viroids)

HBV

fulminant hepatits (higher mortality rate)

detection of anti-HDV IgG antibodies

dinosaurs

• HSV-1
• HSV-2
• Varicella Zoster Virus VZV
• Epstein Barr Virus EBV
• Cytomegalovirus CMV
• HHV6
• HHV7
• HHV8/KHSV

the host cell (w/ glycoprotein spikes)

proteins made by the virus that aid in attachment

• lipid membrane w/ glycoprotein spikes
• tegument
• nucleocapsid
• DNA core

viral proteins that help start the infectious process in cells

icosahedral shaped structure that contains genetic material

genetic material inside the nucelocapsid; usually double stranded linear DNA .

asymptomatic

latent phase

symptoms

certain signals in the host when immune system is weakened

infection

• five
• HSV- 2 and HHV8

keratitis, encephalitis

neonatal HSV2

varicella - chicken pox, zoster-shingles

Burkitt's lympohoma, nasaopharyngeal carcinoma, oral hairy leukopaka

mostly mild or asymptomatic infections

neutopic and lymphoproliferative

kapos's sacoma

acyclovir, valacyclovir

acyclovir, valacyclovir

acyclovir, valacyclovir

ganacyclovir

acyclovir, ganacyclovir

picomarivirdae

fecal - oral route

• abortive and nonparalytic polio (minor)
• paralytic and bulbar poliomyelist (severe)

trivalent, inactivated vaccine

picornaviridae

small single stranded RNA

fecal - oral route

• herpangina and hand foot, mouth diseases
• pleurodyna and heart infections (severe)

no vaccine

rhabdoviridae

single stranded (-) RNA, cells is bullet shape

zoonotic

rabies (highly fatal)

inactivated vaccine

revoviridae

double-caspsid segmented double stranded RNA

fecal - oral route

infantile diarrhea

rotarix and rota Teq

paramyxoviridae

(-) RNA

fruruit bats

requires intermedate host (pigs) then to humans

none

Ribavirin

• flaviviridae
• arbovorus

single straded (+) RNA

monkeys and humans

insect vector

none

None

• flaviridae
• arbovirus

singles stranded (+) RNA

bird

insect vector

not discussed

bunyaviridae

single stranded segmented RNA

small mammals

respiratory route

Hentavax (not FDA approved)

none

lytic replication cycles

• virus bind and enters cell
• nucleocapsid moves through cytoplasm to host nucleus
• nucleocapsid binds to nucleus and injects DNA and tegument
• new viruses are assembled in the nucleus
• viruses bud off of the nucleus and move into the golgi bodies
• viruses exit through cell membrane and evets

epidermal cells and neurons enervating the skin

when it reaches the neroun cell body (end) (latent)

the same area where primary infection occured

almost identically

the face and skull

waist and hip area

disseminated infection b/c of immature immune system

terminates viral DNA chai growth

has to be activated by viral eznymes to start working

the -OH

more avalible to cells

hydrogen

HSV encephalitisq

HSV keratitis

• EBV
• CMV
• the three HHV types

cells of the immune system (t cells, b cells, monocytes,macrophages and dendritic cells)

B cells where it becomes latent

mono

body fluids

monocytes, polymorphonuclear leukocytes and macrophages

embryo, neonates, young children

in cerbral-spinal fluid

encephalitis, causative agent of roseas

not yet associated with any human disease

castleman's disease, primary effusion lymphoma, and body cavity lymphoma

obligate

there are more than 100 types

• asymptomatic
• abortive polio (self limiting)
• nonparalytic polio
• paralytic poliomylitis

75%

• localized
• systemic

weeks or month depending on the bite

• prodome stage - virus infects nerves onset (2 - 10 days)
• neurolgic stage - hallucination, virus to organs (2 -10 days)
• comatose stage and death

rabies

stable (can pass through stomacha)

day of exposure, days 3,7,14 and 28

24-48 hours

zoonotic

human

bovine

good hygiene

3-14 days

4

asi, africa and north america in 1780's

uganda, africa, 1937

1-5 weeks

hantavirus

hantaan river in south korea in 1978

• avian influenza
• monkeypox
• rift valley fever - african cattle and sheep
• h1n1
• XMRV

coexistence where neither orgainsm harms the other

coexistence where both organisms benefit

coexistence where one organism has the potential to harm the other

species in which sexual reproduction occurs

species in thich asexual reproduction occurs

unnatural host that parasite is not adapted to survive in

filoviridae

respiratory or fecal-oral route, (human to human)

none

none

• sarcomastigophora
• apicomplexa

• sarcodina (amoebae)
• mastigophora (flagellates)

entamoeba histolytica

giardia lamblia, trypanosma cruzi

• class sporozoea, suborder eucoccidia
• suborder haemosporina

toxoplasma gondii, cryptosporidium

plasmodium

cysts (can survive high temps and chloride)

cysts change into tropozoites, occurs in small intestines

trophozoites

small peptides that form pores in cell membranes

trophozoites change into cysts, occurs during passage through the gut

cysts ( 1 cysts realeases 8 trophozites)