GI Viruses

Question 1

Picorna virus

Answer 1

(+) RNA virus, naked

Question 2

Picorna viruses are trasmitted via

Answer 2

fecal-oral route

Question 3

Rhinovirus

Answer 3

Picorna virus that is transmitted via respiratory system instead of fecal-oral route

Question 4

(+) RNA Replication

Answer 4

Uses host RNA polymerase to get translated

Question 5

(+) Sense viruses

Answer 5

are same sense as host cell RNA (+)
This allows them to be directly translated to proteins by host cell RNA polymerase
Virus uses host cell’s machinery

Question 6

Picornaviruses translate RNA into long polyprotein product

Answer 6

Viral proteases cleave product into active viral protein subunits

Question 7

All RNA (+) viruses replicate

Answer 7

outside the nucleus in the cytoplasm

(host cell mRNA, which is analagous to viral RNA) is all processed in cytoplasm

Question 8

What are the 3 main subgroups of Picorna viruses

Answer 8

1. Hep A
2. Enteroviruses
3. Rhinoviruses

Question 9

What type of virus is Hep A?

Answer 9

Picorna Virus

Question 10

Hepatitis causes

Answer 10

Hepatosplenomegaly

Question 11

Enteroviruses include

Answer 11

Polio
Coxsackie A and B
Echovirus

Question 12

What is the most common cause of aseptic meningitis?

Answer 12

Enteroviruses

Aseptic = Cause by non-bacterial organism

Question 13

Viral meningitis CSF

Answer 13

normal glucose levels
aseptic (w/o bacteria)
elevated protein levels

Question 14

Who is especially susceptible to viral meningitis caused by enteroviruses?

Answer 14

young children

Question 15

What is a common cause of the common cold?

Answer 15

Rhinovirus

Question 16

Unique features of polio (Picorna virus)

Answer 16

Acid Stable
Replicates in lymphoid tissue and Peyer’s Patches (submucosa of ilium).
Incubation 2-3 weeks

Question 17

Polio virus affects

Answer 17

anterior horn of LMN cell bodies

Question 18

Paralysis occurs

Answer 18

2-3 weeks following infection

Question 19

Polio causes

Answer 19

asymmetric paralysis located in lower legs
myalgias
decreased DTR
Respiratory insufficiency as paralysis ascends to diaphragm. Causes death.

Question 20

Salk Vaccine

Answer 20

Inactivated polio vaccine administered IM

Question 21

Sabin Vaccine

Answer 21

Live, attenuating vaccine administered orally

Question 22

Downside to Salk Vaccine

Answer 22

Since it bypasses GI tract, only produces IgG antibodies (not IgA, the primary immunity in mucosal surfaces).

Question 23

Upside to Sabin Vaccine

Answer 23

Produces both IgG and IgA

Question 24

Downside to Sabin Vaccine

Answer 24

Can be shed in feces and possibly revert to form that can cause paralysis

Question 25

Enterovirus meningitis

Answer 25

self-limiting

Question 26

Coxsackie A

Answer 26

Hand, foot & mouth disease, Red vesicular rash

Question 27

Coxsackie infection is most common in

Answer 27

summer

Question 28

Coxsackie B

Answer 28

Dilated cardiomyopathy | Devil's Grip = Bornholm's Disease = Pleurodynia = Extreme, sharp unilateral chest pain w/ SOB

Question 29

Coxsackie Treatment

Answer 29

Supportive

Question 30

How many G and P combinations are there that are targets for Rotavirus vaccination?

Answer 30

4

Question 31

Riovirus

Answer 31

Rioviridae

Question 32

What makes riovirus unique?

Answer 32

Double stranded RNA virus so (+) vs. (-) classification doesn't apply

Question 33

Where do RNA viruses replicate

Answer 33

Cytoplasm

Question 34

Orthomyxovirus

Answer 34

Replicates in nucleus

Question 35

Riovirus

Answer 35

Naked and 11 segments on average (between 9-12)

Question 36

Rotovirus

Answer 36

Transmitted by fecal-oral route | Causes toxin-mediated secretory diarrhea

Question 37

What is the enterotoxin that causes diarrhea in Rotovirus?

Answer 37

NSP4 | Increases chloride permeability leading to secretory diarrhea

Question 38

When do rotavirus outbreaks occur?

Answer 38

Winter

Question 39

Who is at high risk of catching rotavirus?

Answer 39

Kids: infant or young child in daycare

Question 40

Treatment for rotavirus

Answer 40

Supportive care/Oral rehydration therapy

Question 41

Rotavirus Vaccine

Answer 41

Live attenuated oral vaccine 1st dose: before 4 months old Vaccine is though to increase risk of intusussception due to stimulation and enlargement of Peyer's patches which then act as lead point

Question 42

Calici Virus family has one member

Answer 42

Norovirus

Question 43

Calici/Norovirus

Answer 43

(+) RNA virus | Naked

Question 44

Calici virus/Norovirus produces

Answer 44

One long polyprotein that is cleaved by viral proteases into smaller, active constituents

Question 45

Where is Norovirus common other than cruise ships?

Answer 45

Day care centers and schools.

Question 46

Consumption of what is associated with Norovirus?

Answer 46

raw shellfish

Question 47

Norovirus causes

Answer 47

Explosive, watery diarrhea