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Flashcards in RNA viruses Deck (39)
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1
Q

reoviruses

A

rotavirus
coltivirus

non-enveloped, icosahedral, dsRNA virus

2
Q

Reovirus- Rotavirus

A

non-enveloped, icosahedral, dsRNA reovirus

primary cause of fatal diarrhea in children worldwide (6% of child deaths under age 5)

deadly due to severe diarrhea, vomiting, dehydration, electrolyte abnormalities

3
Q

Reo-virus Coltivirus

A

non-enveloped, icosahedral, dsRNA reovirus

Colorado tick fever
found in mountainous regions of western US and Canada

spread by woodtick to hikers, hunters, and the like

4
Q

Picornavirus- enterovirus

A

non-enveloped, ss+ linear, icosahedral

enteroviruses include poliovirus, coxsackivirus, and echovirus

primary spread via feco-oral route, alternatively resp secretions

5
Q

polio

A

this is a picornavirus, icosahedral, non-enveloped, ss+linear RNA

it affects the anterior horns of the spinal horn, and motor neurons of the pons and medulla leading to paralysis

  1. salk vaccine- killed and injected
  2. sabin vaccine- live and eaten
6
Q

Echovirus

A

picornavirus, enterovirus
ss+linear RNA
non-enveloped
icosahedral

summer outbreaks of
viral meningitis
URI
myocarditis

detection is possible via PCR of CSF, which enables outpatient care and conservation of healthcare resources (not much treatment needed for viral meningitis)

7
Q

Coxsackivirus

A

picornavirus, enterovirus, ss+ linear RNA, icosahedral, non-enveloped

hand-foot-mouth disease
viral myocarditis, pericarditis
aseptic meningitis
herpangina
febrile pharyngitis
8
Q

HAV

A

picornavirus, ss+linear RNA, icosahedral, non-enveloped

feco-oral spread

9
Q

Rhinovirus

A

picornavirus, ss+linear RNA, icosahedral, non-enveloped. common cold. >100 serologic types.
Acid labile, destroyed by stomach acid, and does not infect the GI tract (unlike other picornaviruses)

10
Q

Calicivirus- Norwalk virus

A

nonenveloped, icosahedral, ss+linear
viral gastroenteritis
vomiting, diarrhea, point- source outbreaks

cruise ship
nursing home

11
Q

Flavivirus

A

Enveloped, SS+linear, icosahedral
includes arboviruses (arthropod-borne)
includes yellow fever and hep C, which turn the skin yellow

12
Q

Flavivirus- Arbovirus- Yellow fever virus

A

a flavivirus
enveloped
ss+linear
icosahedral

yellow fever-
Aedes mosquito
reservoir- humans and monkeys
Sub-Saharan Africa and South America

hemorrhagic disease (epistaxis, petecheal, purpuric gum lesions, black vomitus, Councilman bodies on liver biopsy)
high fever
jaundice

13
Q

Flavivirus- Arbovirus- Dengue virus

A

ss+RNA linear, enveloped, icosahedral

most common mosquito-born disease worldwide

classic breakbone fever-
retroorbital pain
joint pain
HA

complication- dengue hemmorhagic fever= thrombocytopenia and increased capillary wall fragility

14
Q

Flavivirus- arbovirus- WNV

A

ss+linear, enveloped, icosahedral

endemic in USA since 1999
flu-like sx are common: HA, malaise, back pain, myalgia, anorexia 3-6 days

severe sx in 1/150: meningitis/encephalitis, flaccid paralysis (anterior horn involvement), alterations in consciousness, death

Dx with serology for WNV IgM abs, serum or CSF

15
Q

Arboviruses that cause encephalitis

A

St. Louis encephalitis virus
Eastern equine encephalitis virus
Western equine encephalitis virus
California encephalitis virus

16
Q

flavivirus- arbovirus-st. louis encephalitis

A

ss+RNA linear, enveloped, icosahedral

arbovirus (mosquito- born)

can cause encephalitis

17
Q

Togavirus- Rubella

A

ss+linear RNA, enveloped, icosahedral

congenital disease leads to 
cataracts
deafness
heart defects
-PDA
-pulmonic stenosis

blueberry muffin

18
Q

Coronavirus

A

enveloped, ss+linear, helical

“common cold” and SARS

19
Q

common cold

A

rhinovirus

coronavirus

20
Q

Retrovirus- Human T cell leukemia virus

A

enveloped, SS+linear RNA, 2 copies, icosahedral

uses reverse transcriptase

21
Q

infects motor neurons of the anterior horn

A

poliovirus

WNV

22
Q

Orthomyxovirus- influenza

A

enveloped, helical, ss (-)RNA
hemagglutinin promotes viral attachment to host cell

neuraminidase promotes release of progeny virions

rapid genetic change
-reassortment= shift, which leads to pandemics
rearrangement= drift, which leads to seasonal epidemics

patients are susceptible to viral PNA and serious bacterial infections with s. aureus, s. pneumoniae while they are infected with influenza

23
Q

mechanism of action for zanamivir, oseltamavir

A

inhibit neuraminidase
virion not released from host cell
use only in severe influenza, must be administered within 24 hrs of symptom onset

24
Q

Paramyxovirus- parainfluenza

A

ss-RNA linear, nonsegmented
enveloped
helical

parainfluenza virus- croup
seal- like barking cough, inspiratory stridor that mimics asthma
steeple sign on xray
pulsus paradoxus secondary to upper airway obstruction

25
Q

paramyxovirus- respiratory syncytial virus

A

ss-RNA linear, nonsegmental, enveloped, helical
bronchiolitis +/- PNA in the small bronchioli of babies

winter

brassy cough, wheezing, respiratory distress
passive immunization with palivizumab (monoclonal RSV immunoglobulin), monthly during the winter months in premature infants, or infants who have chronic lung disease

treatment: supportive
NOT ribavirin

26
Q

winter viruses

A

influenza
rotavirus
RSV

27
Q

summer viruses

A

enteroviruses
-poliovirus, echovirus, coxsackivirus

arbovirus- WNV

28
Q

Ribavirin

A

guanosine analog
approved for RSV, hepatitis C

no longer recommended for RSV

side effects:
teratogenicity, hemolytic anemia

29
Q

Rubeola- paramyxovirus

A

ss-RNA linear, nonsegmental, enveloped, helical

cough
coryza (runny nose)
conjunctivitis
maculopapular rash descending from head to toe
Koplik spots early on (blue grey spots on buccal mucosa, surrounded by a base of red

complications- years later there may be subacute sclerosing panencephalitis (SSPE), or giant cell PNA (immunocompromised host)

30
Q

Mumps- paramyxovirus

A

ss(-)RNA linear, nonsegmented, enveloped, helical

parotitis, orchitis (possible future sterility), meningitis

31
Q

Viral meningitis

A

coxsackievirus
echovirus
enterovirus
mumps virus

32
Q

Rhabdovirus- rabies

A

ss(-) linear RNA, enveloped, helical

transmission from bat, raccoon, skunk, dog to human
infection is retrigrade vie neurons and ACHR to hippocampus and purkinke cells of cerebellum

Negri bodies are eosinophilic cytoplasmic inclusions

symptoms manifest months to years later

fever/malaise/n/v progresses
to hydrophobia, photophobia, agitation, hypersalivation

progresses to coma and death

33
Q

Bunyavirus- hantavirus

A

ss(-) 3 segments of RNA, enveloped, helical

hemorrhagic fever
pulmonary syndrome
-fever
-progressive pulmonary edema
-respiratory failure

spread by aerosolized deer mouse urine

34
Q

segmented viruses

A

Bunyaviruses
Orthomyxoviruses
Arenaviruses
Reoviruses

35
Q

mouse urine

A

lassa virus (Arenavirus)
LCMV (arenavirus)
hantavirus

36
Q

Filoviruses

A

ss-RNA, linear, enveloped, helical

Ebola and Marburg viruses

Ebola spread through fluids
fever, HA, myalgia
leading to vomiting, diarrhea, fluid loss, electrolyte imbalance, multiorgan failure, shock, death

treatment: supportive
prevention is key (contact and droplet isolation to prevent transmission of someone has been exposed)

37
Q

characteristic “barking seal” cough

A

croup

38
Q

childhood diarrhea in winter months

A

rotavirus

39
Q

asthma- sounding infection in infants (esp preemies)

A

paramyxovirus

RSV