Viral Infections of the Upper Respiratory Tract

Question 1

What are the most common causes of common cold (in order)?

Answer 1

Rhinovirus, Coronavirus, Influenza Virus, Respiratory Syncytial virus, Parainfluenza virus, Adenovirus

Question 2

How do viral infections reach the respiratory tract?

Answer 2

Virions reach resp tract via fomites or aerosols

Question 3

What is the site of virus-host interaction?

Answer 3

Respiratory epithelium

Question 4

What causes the typical symptoms of a viral infection?

Answer 4

Epithelial cell release of cytokines

Question 5

What characteristic of the upper respiratory tract allows for viral pathogenesis?

Answer 5

Lower temperature (33C), therefore rhinovirus prefers URT

Question 6

What age group has more severe URT infections?

Answer 6

Infants and elderly

Question 7

What pathogens are associated with acute URT infection?

Answer 7

Picornavirus (rhinovirus), Coronavirus, Paramyxovirus (Parainfluenza and RSV, Orthomyxovirus (Influenza)

Question 8

What viruses are associated with persistent replication in URT?

Answer 8

EBV, adenovirus, papillomavirus

Question 9

What viruses are associated with systemic replication (dissemination) after primary replication in respiratory tract?

Answer 9

Paramyxovirus (Mumps, Measles), Herpesviruses (EBV, VZV, HHV6, CMV), Rubella, Picornavirus (Polio)

Question 10

What are barriers to virus from resp tract to blood?

Answer 10

Body temperature, Basement membrane

Question 11

What are the risk factors for virus dissemination into the blood?

Answer 11

Immunocompromised, smoking, drinking, intubation, bed-ridden

Question 12

What type of virus is coronavirus? What type of Syx with infection? What are two new rare strains?

Answer 12

(-)ssRNA virus, Cold-like Syx, SARS 2003, MERS 2013

Question 13

What are Myxoviruses?

Answer 13

Myxo-Greek for mucus, these viruses bind to mucin protein on RBCs

Question 14

What is an Orthomyxovirus?

Answer 14

Straight, right, proper; Influenza virus is the “right” one

Question 15

What is a Paramyxovirus?

Answer 15

Beside, resembling; Measles virus is similar to orthomyxoviruses, but different so classified differently

Question 16

Representatives, Replication, Genome and Structure of Orthomyxoviridae

Answer 16

Genus - Influenzavirus Types: A, B, C; Nuclear; Segmented (-) ssRNA, Enveloped

Question 17

Representatives, Replication, Genome and Structure of Paramyxoviridae

Answer 17

Genera: Paramyxovirus(Mumps, Parainfluenzavirus1-4) Morbillivirus (Measles, Canine Distemper), Pneumovirus (RSV); Cytoplasmic; Non-segmented (-) ssRNA, Enveloped

Question 18

What are three treatments of the flu and what strains do they target?

Answer 18

Tamiflu - A, B; Relenza - A, B; Amantadine/Rimantadine - A

Question 19

What is Fluzone?

Answer 19

Trivalent inactivated flu vaccine

Question 20

What is Flumist?

Answer 20

Live attenuated flu vaccine

Question 21

What are the three strains in the trivalent flu vaccine?

Answer 21

A/California/7/2009 (H1N1), A/Texas/50/2012(H3N2), B/Yamagata lineage

Question 22

What are two common Paramyxoviridae?

Answer 22

Mumps and parainfluenza virus

Question 23

What are characteristics of Respiratory Syncytial Virus infection? Tx? Complications?

Answer 23

Can cause croup; Steam and humidifiers; pneumonia and respiratory distress

Question 24

How is adenovirus transmitted?

Answer 24

Fomites, Aerosols, Close contact

Question 25

Adenovirus at-risk populations

Answer 25

Day care centers, military camps, swimming clubs

Question 26

What vaccines are available for adenovirus?

Answer 26

Live, attenuated vaccine for serotypes 4 and 7