Micro-Varicella & Herpes Viruses

Question 1

Herpesvirus structure

Answer 1

Linear, ds DNA large icosahedral enveloped nonsegmented

Question 2

HHV 6 classification/tropism

Answer 2

Betaherpes - lymphotrophic

Question 3

HHV 7 classification/tropism

Answer 3

Betaherpes - lymphotrophic

Question 4

Describe herpes virus latency

Answer 4

• No virus produced
• Genome maintained extrachromosomally
• Few genes expressed
• 3 stages - establishment, maintenance, reactivation

Question 5

Describe VZV tropism

Answer 5

neurotropic

Question 6

VZV presentation

Answer 6

Fever followed by itchy rash that begins on scalp and trunk

Adult cases are more severe, and can result in pneumonia

Question 7

VZV incubation time until symptomatic?

Answer 7

14 days; starts with infection of eye/RT mucosa and progresses down lymph nodes to other organs

Question 8

Zoster presentation

Answer 8

Sudden onset of pain and rash along thoracic dermatome or forehead

May last 2-4 weeks with post-viral neuralgia

Question 9

Describe VZV vaccine

Answer 9

Live attenuated treats chickenpox and zoster but causes lifelong latency

Can boost immunity to prev/lessen zoster

Question 10

Treatment option for adult VZV pneumonia

Answer 10

Ig

Question 11

Zoster treatment, generally

Answer 11

ACV and steroids

Question 12

HHV6 and HHV7 cause:

Answer 12

Roseola (exanthem subitum)

Question 13

Roseola presentation

Answer 13

Mild RT then fever; ~25% kids have post-viral rash for a few days that characteristically blanches

High fever is characteristic