Infectious exam 3

viruses are (three words). they must get inside living cells to multiply

obligate intracellular parasites

viruses rely on host cell for almost all

nucleic acid replication

metabolic pathways that provide energy

the purpose of RNA is to

encode the viral genome

purpose of protein coat is to protect the fragile nucleic acid, and

ensure its delivery to the target cell

this scientists proposed that you can classify viruses based on their Replication system

Baltimore

dsDNA

type 1 viruses

examples of type 1 viruses

adenoviruses

herpesviruses

poxviruses

ssDNA

type 2 virus

dsRNA

type 3 virus

(+)ssRNA

type 4 virus

(-)ssRNA (antisense strand)

Type 5 virus

ssRNA-RT

type 6 virus

dsDNA-RT

type 7

extending form capsomeres that allows attachment to host cell

spike protein

what is the capsid composed of

capsomeres

capsid is surrounded by a lipid membrane called an

envelope

proteins embedded in the membrane

viral attachment protein

largest known animal viruses that infect humans

pox viruses

pox virus encodes over ___ genes

200

only known DNA virus that replicates in the cytoplasm, does not require host cell nucleus or any of its sources

Pox virus

causes a severe form of smallpox with a fatality rate of 30-40%

variola major

causes a more mild form of smallpox with a fatality rate at about 1%

variola minor

les virulent, yet highly related to smallpox, it is the cowpox (vacca) virus that is safe enough to study experimentally

vaccinia

in this family, there is only 2% difference in the sequence and all proteins are virtually identical

Orthopoxvirus family

Five distinct clinical manifestations of m=variola major infection

(70% of cases)type of variola major with a confluent rash that develops on the face first and then spreads

ordinary type

similar to ordinary type, but the progression of the disease is accelerated and lesions are smaller in size

modified type

variola infection that produces fever but no rash. this is a feature of partial protection, exhibited by individuals who were vaccinated or who have previously had smallpox

variola sine eruptione

variola in which pustules are not raised and tend to be confluent or semiconfluent, this is frequently fatal

flat type

type of variola where skin and mucous membrane lesions become hemorrhagic, accompanied by profound prostration, diffuse bleeding and heart failure death can occur in a few days

hemorrhagic type

pox viruses: these sop up real cell cytokines and sequester them from their legitimate cellular target

receptor decoys

pox viruses masquerade as legitimate host products and inhibit and misdirect immune responses

pseudo-cytokines

pox viruses: these prevent cell activation and even apoptosis

intracellular signaling pathway inhibitors

there are enough shared determinants between cowpox and smallpox that antibodies against one virus can

neutralize the other virus

you only have to vaccinate against this virus in order to be immune to cowpox

smallpox

minimally infectious during this period before symptoms

prodromal

Herpes started slide 7

take notes on everything else

in genital infections site of latency is

sacral ganglia

in herpes what happens in the site of active lesions

virus replication in epithelium

initial out break of herpes is normally

worse than the rest

caused by hsv 1 or 2, lesion found on finger and thumbs, most commonly contracted by healthcare workers(dentists that may be bitten), contact with oral secretions

herpes whitlow

herpes caused by skin-to-skin contact, rubbing, common in wrestlers transmitted via contact sports

herpes gladitatorum

the three forms of neonatal herpes

skin eyes, and mouth, disseminated, CNS

how is neonatal herpes transmitted

during birth, in utero, postantally

mothers with known herpes history should take ________ during pregnancy

acyclovir

herpes is normally controlled by

type 1 interferons, NK cells, T cells, CD8 cytotoxic T cells

antibodies are not considered protective for HSV but they are crititcal for

chicken pox

passive strategy on how HSVs evade immune response

latency

some trigger of HSV recurrences

UV radiation, fever, stress acidic foods immunesuppression

causes chicken pox

varicella zoster virus

how vsv is spread

aerosol transmission

reactivation if VSV

shingles

shingles is normally a stipe of tissue limited to

one area of the body

band of skin that shingles affects

dermatome

why does this stripe occur for vsv

VSV can only affect a single spinal nerve at a time

Epstein barr virus infects what kind of cells

b cells

aka kissing disease weariness, sore throat, very swollen tonsils/lmyph nodes etc

mononucleosis

disease that appears in sheep and and they start wasting, tremors occur, have compulsive desire to scratch against things eventually wearing away fleece and erode hide

scrapie

scrapie transmission

via mother’s milk and directly between sheep

human form of scrapie

Creutzfeldt-Jakob disease

disease causing protein that is the misfolded version of a normal cellular protein

Prions

PrPc is converted to

Prpsc

prions change other protein configuration by

contact

types of prion diseases

spontaneous inherited acquired

capable of denaturing prions

bleach, NAOH, acidic diseases

started slide 6 for rabies

five proteins encded by rabies virus structure RNA genome

glycoprotein ribonucleoprotein matrix protein polymerase phosphoprotein

protein that exists as approximately 400 trimer spikes covering viral surface, these are embedded in the envelope

glycoprotein

tightly encases RNA genome

ribonucleoprotein

associates with both membrane and N protein providing structure

matrix protein

protein that helps replicate genome

matrix protein

inhibits interferon response

phosphoprotein

Rabies virus replication slides 7-9

pathognomonic

characteristic of a certain disease

rabies is almost always transmitted via bite, but there is evidence that it can be passed via

aerosolized saliva through organ transplantation

incubation period of rabies depends on what three factors

size of inoculum, distance of site of infection from brain, host immune status

rabies subverting immune response slide 12

filoviridae taxonomic group (filoviruses) example

ebola and marburg virus

arenaviridae (arenavirues) taxonomic group examples

Lassa fever, machupo viruses

bunyaviridae (bunyavirueses) taxonomic group example

hanta fever virus

flaviviridae examples

yellow fever dengue west nile

severe fever inducing illness with evident dysregulation of vascular function and significant vascular damage

viral hemorrhagic fever (VHF)

a feature that define hemorrhagic fever

direct vascular damage

virus that has string-like characteristics, normally has a hook like structure

filovirus

5 members of the filoviridae group

ebola zaire ebola sudan ebola bundibugyo cote d’ivoire ebola reston

final cause of death of ebola

multiple organ failure and shck

death of ebola looks a little like

endotoxic shock

cells that ebola infects

macrophages, dendritic cells, monocytes, endothelial cells, hepatocyets

ebola transmission

bodily fluids, fomites (needles syringes) lack of protective gear

enterovirus lecture started slide 8, will not test on all these steps though, just the receptors

polio virus is what kind of virus

enterovirus

what does enetrovirus mean

of the gut

three antigenically distinct strains of wild-type poliovirus

mahoney lancing leon

how is poliovirus soread

fecal oral route

95 percent of polio cases

asymptomatic

polio virus first gains access to and replicates in these tissues

brown fat reticuloendothelial tissues, and muscle

in polio there is a wave of _____ ____ then replication occurs and lead to _____ _____

primary viremia secondary viremia

symptoms of polio after secondary viremia

sore throat, fever, body aches

once secondary viremia sets in possibility of ________ ________ develops

paralytic poliomyelitis

poliovirus enters the CNS and replicates in the

motor neurons