RNA Viruses Flashcards Preview

Step 1 > RNA Viruses > Flashcards

Flashcards in RNA Viruses Deck (19):
1

Reoviruses

Coltivirus
Rotavirus

unenveloped ds+RNA segmented icosahedral

Colorado tick fever
fatal diarrhea in children

2

Rotavirus

pathogenesis

who to not vaccine?

Reovirus (unenveloped ds+RNA segemented icosahedral)

villous destruction w/ atrophy => decreased absorption of Na & loss of K

h/o SCID or intussusception

3

Picornovirus

PERCH

enteroviruses & aseptic meningitis except?

unenveloped ss+RNA linear, icosahedral

P - polio - anterior spinal cord LMN death
E - echo
R - rhino (common cold, acid labile)
C - cocksackie (hand foot mouth disease; causes herpangia - mouth blisters & fever)
H - HAV - acute self limiting viral hepatitis

HAV and rhinovirus

4

Hepevirus

HEV

unenveloped ss+RNA linear icosahedral

fulminant hepatits in pregnant women

5

Calcivirus

Norovirus

enveloped ss+RNA linear icosahedral

gastroenteritis

6

Flavivirus

HCV
Yellow fever (an arbovirus)
Dengue
St.Louis encephalopathy
West Nile virus
Zika virus

enveloped ss+RNA linear iscosahedral





West Nile virus - meningoencephalitis

7

Yellow Fever (an arbovirus)

transmission & reservoir
p/w
histology of liver bx

Flavivirus (enveloped ss+RNA linear, icosahedral)

aedes misquito; human & monkey reservoir
fever, jaudince, black emesis
councilman bodies - eosinophilic apoptotic globules

8

Zika virus

transmission
outbreaks common where?
p/w
fetal effects
dx
tx

Flavivirus (enveloped ss+RNA linear icosahedral)

Aedes misquito; sexual and vertical possible
tropical & subtropical areads
conjunctivitis, low grade fever & pruritic rash
microcephaly or miscarriage
RT PCR or serology
supportive, no definitive

9

Togavirus

Rubella
Western & Eastern Equine virus
Chikungunya

enveloped ss+RNA linear icosahedral

10

Rubella

aka
p/w
congenital

Togavirus (enveloped ss+RNA linear icosahedral)

german (3-day) measles
fever, LAD, arthralgias, centripetal rash (head-->trunk & extremities)
TORCH infxn:
p/w sensorineural hearing loss, cataracts & congenital heart defects (ie PDA) + blueberry muffin rash (dermal extramedullary hematopoiesis)

11

Retrovirus

HIV
HTLV

enveloped ss+RNA linear (x2)

HIV - AIDS, conical capsid
HTLV - T cell leukemia, icosahedral capsid

12

Coronaviruses

enveloped ss+RNA helical

common cold, SARS, MERS

13

Orthomyxovirus

influenza
antigens
superinfxn but what?

genetic shift caused by? causes?
genetic drift caused by? causes?

enveloped ss-RNA helical

hemagglutinin - binds sialic acid => viral entry
neuramidase - virion progeny release
H flu S aureus S pneumo

recombination, pandemic
random mutation, epidemic

14

Paramyxoviruses

Parainfluenza
RSV
Measles
Mumps

virulence factor
Palivizumab

enveloped ss-RNA linear, helical

croup - laryngotracheobronchitis
bronchiolitis in babies



surface protein F (fusion protein) => resp epithelial cells for multinucleated cells

monoclonal ab against F protein - given as ppx to premature infants to prevent RSV pneumonia

15

Parainfluenza

antigens
p/w
imaging

paramyxovirus (enveloped ss-RNA linear, helical)

hemagglutinin (entry) and neuramidase (release)
croup - acute laryngotracheobronchitis
=> barking cough, inspiratory stridor, pulsus parodoxus if severe

XR - steeple sign (narrowing of upper trachea & subglottis)

16

Measles (rubeola) virus

p/w
histology
role of vit A
possible sequelae

paramyxovirus (enveloped ss-RNA linear, helical)

coryza, conjuntivitis, cough
=> Koplik spots (bright red spots w/ blue-white center on buccal mucosa)
=> maculopapular rash centripetal (head-->down)

lymphadenitis w/ warthin-finkeldey giant cells (fused lymphocytes) in background of paracoritcal hyperplasia

vit A can reduce morbidity & mortality, particularly in malnourished children

1 - SSPE (subacute sclerosing panencephalitis, can be yrs later)
2 - encephalitis
3 - giant cell PNA in immunocompromised

17

Mumps virus

p/w POMP
can cause ____ after puberty

Paramyxovirus (enveloped ss-RNA linear, helical)

P - parotitis
O - orchitis (inflammation of testes)
M - aseptic meningitis
P - pancreatitis

can cause infertility

18

Rhabdovirus

histology
transmission
pathogenesis
p/w

enveloped ss-RNA linear, helical

bullet shaped virus
negri bodies in purkinjie cells in cerebellum & hippocampus

rat racoon bat dog bite; aerosol possible

long incubation period (can give post exposure ppx)
travels to CNS via dynein (retrograde) after binding AChR

p/w fever, malaise
=> agitation, photophobia, hydrophobia, hypersalivation
=> paralysis, coma & death



19

Filoviruses

Ebola virus

transmission
pathogenesis
p/w
dx
tx

enveloped ss-RNA linear, helical


bodily fluids, fomites, infexted bats/primates, nosocomial

incubation - 21d
targets endothelial, phagocytes, & hepatocytes

p/w flu like sx, N/V/D, high fever, myalgia
=> DIC, diffuse hemorrhage, shock

RT PCR w/in 48hr of sx onset

supportive care only