Infectious Disease -- Viral Illness III

Question 1

Genetic information for Polio

Answer 1

Picornaviridae

Nonenveloped RNA

Question 2

Polio Disease Progression

Answer 2

• Infects Oropharynx, where it is secreted into saliva
• Saliva swallowed, multiplication in the intestinal mucosa and LN
• 1% invasion of CNS to replicate in MNeurons – Paralysis

Question 3

The cellular receptors used by polioviruses are members of the ________ family

Answer 3

Immunoglobulin SUperfamily (Chromosome 19)

Question 4

What other example of the immunoglobulin superfamily have we seen already?

Answer 4

iCAM (binder of Integrins)

Question 5

Name the two Polio Vaccines

Answer 5

Salk – Inactive

Sabin – Oral, Live attenuated

Question 6

Salk Vaccine – Duration of Immunity? Risks?

Answer 6

Requires Booster Vaccine

No risk of paralytic disease

Question 7

Sabin Vaccine – Duration of Immunity? Risks?

Answer 7

Risk of paralytic dissease, esp in IC patients

Greater duration of immunity

Question 8

Bonus perk of the Sabin vaccine

Answer 8

“Free Immunizations” by virus shed in stool

Question 9

Common viral URT infections

Answer 9

1. Rhinovirus
2. Coronavirus
3. Adenovirus
4. Echovirus

Question 10

Common viral LRT infections

Answer 10

1. Influenza
2. Parainfluenza
3. RSV

Question 11

What do you need to remember about RSV?

Answer 11

Kills Babies

Question 12

Common viral GI Tract/Liver Infections

Answer 12

1. Rotavirus (kids)
2. Norwalk (Cruises)
3. Hepatitis

Question 13

Rhinovirus causes how many common colds?

Answer 13

more than 50%

Question 14

Rhinovirus binds to

Answer 14

ICAM-1

this lets it infect any human/primate with ICAM-1 on their epithelial cells

Question 15

Why does Rhinovirus only infect URT?

Answer 15

Virus needs cooler environment

Question 16

Damage caused by Rhinovirus

Answer 16

Hypersecretion due to bradykinins and inflammatory response

Question 17

Why do we keep getting infected with Rhinovirus

Answer 17

Antibody only blocks re-infection with the same serotype, but not others

Question 18

Important details about coronavirus

Answer 18

Second most common cause of common cold

Profuse Nasal Discharge, little effect on lower resp. tract

Question 19

Important details about Echovirus and Coxsackie Virus

Answer 19

Non-polio enteroviruses
Fecal/Oral spread, Dissemination in bloodstream after prolif. in lymphoreticular tissues
Primarily cause respiratory disorders (longer dissemination)

Question 20

Types of influenza

Answer 20

A, B, C
Groupsed by nucleoprotein
Subtyped by Hemagglutinin and neuraminidase

Question 21

What is Hemagglutinin?

Answer 21

It binds to sialic acid-containing proteins and lipids on most cells
Mediates entry into the cell

Question 22

What is neuraminidase?

Answer 22

Plays a role in releasing virus from host cells

Cleaves Sialic Acid

Question 23

What happens in Influenza that allows epidemic spread

Answer 23

Shifts and Drifts

Question 24

Which type of Influenza are the major cause of pandemic/epidemic flu?
Which type infects mostly children?

Answer 24

A

B and C

Question 25

Pathology of Influenza viruses

Answer 25

Mucosal hyperemia with lymphomonocytic and plasmacytic infiltration of the submucosa Hypersecretion

Question 26

Most influenza deaths are caused by...

Answer 26

secondary bacterial infection.

Question 27

Difference between antigenic drift and shift?

Answer 27

Drift -- Mutation from year to year | Shift -- Introduction of new subtype generated by recombination

Question 28

What is Croup? What causes it?

Answer 28

Acute, febrile laryngotracheobronchitis with insp. stridor, horaseness, and barking cough Parainfluenza type 3

Question 29

Most common cause of viral pneumonia in children under 2 years old?

Answer 29

RSV

Question 30

Most common cause of death in infants 1-6 months

Answer 30

RSV

Question 31

Important details to keep about Adenovirus?

Answer 31

Common cause of Acute respiratory disease + pneumo in military recruits. Cowdry Type A Nuclear Inclusions Epithelial Cell necrosis w/ sloughing

Question 32

Viral pneumonias common in immunosuppressed?

Answer 32

CMV Chickenpox (varicella) Herpes Simplex

Question 33

Two fecal/oral viruses that cause GI disease

Answer 33

Coxsackie | Poliovirus

Question 34

Important details of Rotavirus

Answer 34

- Acute, self-limited - Infectious diarhea - Mostly Among Children/Infants - Fecal/Oral

Question 35

Most common time of Rotavirus onset

Answer 35

Weaning (IgA in mother's milk is mildly protective)

Question 36

Important details of Norwalk agent

Answer 36

- Epidemic viral gastroenteritis | - Naked, icosahedryl nucleocaspids which cannot grow in cultured cells

Question 37

Other than common cold, coronavirus can also cause...

Answer 37

diarrhea

Question 38

Three main ways that viruses are spread

Answer 38

1. Respiratory 2. Fecal/Oral 3. Infected Body Fluids

Question 39

How do viruses spread within a person

Answer 39

1. Local disease 2. Hematagenous disseminated 3. Transmission thru nerve

Question 40

Most common pathology of viral infections

Answer 40

Lymphocytic infiltrates Inclusion bodies Cytopathic response Syncytia (in RSV and Late HIV)