22 - Positive Strand RNA Viruses (Stapleton)

Question 1

+ strand RNA naked viruses

Answer 1

picornavirus

calicivirus

Question 2

+ strand RNA enveloped virus

Answer 2

flavivirus
togavirus
retrovirus
coronavirus

Question 3

picornavirus subgroups

Answer 3

rhinovirus-common cold
hep a-GI
enterovirus- GI (poliovirus, coxsackievirus)

Question 4

lifecycle of picornavirus

Answer 4

attachment
genome released into cytoplasm
cell ribosomes bind genome and make polyprotein
polyprotein is cleaved by viral protease
RDRP creates - strand RNA
RDRP copies - strand to make + strand
caspid assembles
particle released

Question 5

picornavirus transmission

Answer 5

rhinovirus-respiratory droplets, secretions
enterovirus- fecal oral
respiratory

Question 6

most common cause of URI

Answer 6

rhinovirus

Question 7

rhinovirus

Answer 7

picornavirus
replicate in URT
does no t cause cytopathic effect
weak and short lived immune response
no antiviral or vaccine

Question 8

poliovirus life cycle

Answer 8

mucosal surface
lymph nodes
viremia
extraneural tissue
retrograde to spinal cord

Question 9

poliovirus causes

Answer 9

poliomyelitis

faccid paralysis

Question 10

poliovirus treatment/prevention

Answer 10

no antiviral agents
vaccination-3 doses
inactivated (salk)
attenuated (sabin)-not used in u.s.
inactivated doesn't protects against GI infections

Question 11

non polio enterovirus symptoms

Answer 11

GI
pancreatitis
fever
rash
hand-foot-mouth disease
meningitis
paralysis
URI

Question 12

hep a virus characteristics

Answer 12

picornavirus
highly stable
highly infectious

Question 13

hep a treatment

Answer 13

no treatment but good vaccine

Question 14

hep a symptoms

Answer 14

fecal oral spread, food borne
symptoms start 4 weeks after infection
fever, nausea, diarrhea, vomiting, jaundice

Question 15

jaundice is common in who that have hep a

Answer 15

more common in adults

uncommon in

Question 16

test for hep a

Answer 16

high ALT-liver damage

IgM antibodies-acute disease

Question 17

calicivirus and hep e characteristics

Answer 17

naked
icosahedral
non segmented
very stable
fecal oral
person to person
food borne

Question 18

norwalk/norwalk like/norovirus

Answer 18

world wide
gastroenteritis
difficult to control because of stability
difficult to decontaminate

Question 19

hep e virus

Answer 19

acute
fecal oral transmission
fatal in pregnant women
no treatment, no vaccines

Question 20

flavivididae characteristics

Answer 20

icosahedral
+ RNA
enveloped
nonsegmental RNA

Question 21

genera of flaviviridae

Answer 21

flavivirus
hepacivirus
pegivirus
pestivirus

Question 22

flavivirus transmission

Answer 22

west nile example
amplifying host (insect, mammal)
vector (mosquito)
dead end host (human, horse)

Question 23

dead end host

Answer 23

insufficient viremia generated for productive maintenance of virus in population

Question 24

flavivirus causes what

Answer 24

hemorrhagic fevers

Question 25

dengue virus

Answer 25

flavivirus dengue fever-break bone disease dengue hemorrhagic fever/shock syndrome-lethal, following prior dengue infection

Question 26

Arthropod borne

Answer 26

arbo flavivirus alphavirus

Question 27

hepacivirus

Answer 27

flavivirus Hep C chronic, slowly progressing hepatocellular carcinoma

Question 28

testing for hepacivirus

Answer 28

serology (antibodies) | if ELISA positive-PCR

Question 29

hepacivirus transmission

Answer 29

blood borne IVDU exposure to body fluids sex with IVDU

Question 30

togavirus types

Answer 30

rubella | alphavirus

Question 31

togavirus characteristics

Answer 31

enveloped icosahedral non segmented RNA

Question 32

alphavirus

Answer 32

arbovirus mild-slight fever/headache severe-encephalitis: headache, fever, coma, tremors, convulsion, death no antiviral or vaccine

Question 33

rubella

Answer 33

togavirus

Question 34

rubella spread

Answer 34

respiratory or intrauterine

Question 35

rubella symptoms

Answer 35

fever, rash, arthralgia | congenital leads to fetal damage (deafness, blindness, mental retardation, heart disease)

Question 36

rubella treatment

Answer 36

no antiviral | MMR vaccine-live attenuated

Question 37

Corona virus characteristics

Answer 37

``` enveloped non segmental helical + strand RNA no treatment or vaccine ```

Question 38

coronavirus strains

Answer 38

5 human strains 3 are common cold 2 are SARS and MERS

Question 39

SARS origin

Answer 39

Guangdong, China

Question 40

SARS symptoms

Answer 40

high mortality viral pneumonia fever, cough, SOB, HA, death from lung damage

Question 41

SARS transmission

Answer 41

from chinese horseshoe bats | civet cat as intermediate hose

Question 42

MERS transmission

Answer 42

from camels

Question 43

acute infections

Answer 43

IgM

Question 44

what + RNA have treatments

Answer 44

HCV

Question 45

what + RNA have vaccines

Answer 45

polio, YFV, HAV_