Viruses

Question 1

Picornaviridae - Coxsackievirus

Answer 1

Non-enveloped, capsid protein binds to host cell receptors
(+) ssRNA, non-segmented, linear
transmitted: fecal-oral, contact with respiratory droplet
affects different types of cells, causes cell death when released
lysis
Endocytosis

Question 2

Measles (Rubeola) Virus

Answer 2

Paramyxoviridae, Enveloped, hemagglutinin bind to host cell receptor
(-) ssRNA, negative sense, non-segmented, linear
Transmission: human only virus, high contagious, respiratory secretions
budding
Fusion

Question 3

Roseola Virus (HHV6)

Answer 3

Herpesviridae - enveloped, dsDNA (linear)
Reservoir: Human-only pathogen
Respiratory secretions, aerosols, contaminated surfaces/fomites
Over 90% of human population infected within first 3 years of life
Exocytosis
Fusion

Question 4

Paravoviridae = Parvovirus

Answer 4

Non-enveloped, capsid spike protein helps bind to progenitor
Transmission: Respiratory droplets, aerosols, can do vertical to fetus, blood donation, 50% > 18 in US have antibodies
Infects erythroblasts: aplastic anemia
Endothelial cells: rash
Immune complexes: rash, artralgias
Lysis
Endocytosis

Question 5

Envelope vs Non-envelope

Answer 5

Envelope must remain wet!
Non-enveloped tend to be more environmentally stable

Question 6

Biphasic

Answer 6

initial illness goes away, followed by a different illness causes by same virus during same infection
NOT the same as latent, reactivated

Question 7

Patterns of viral infection

Answer 7

Parvovirus: acute, one and done
Hep C: persistent chronic
Herpes: Latent, reactivating
HIV: slow, persistent, with acute and then late-stage disease and symptoms
JC virus: slow chronic infection