VZV and Herpes 6/7

Question 1

What type of genetic material so herpesviruses have?

Answer 1

Linear, ds DNA genome of 150-250 kbp

Question 2

What are the structural features of herpesviruses?

Answer 2

Icosahedral capsid
Enveloped
Dozen glycoproteins

Question 3

Where are nucleic acids replicated in herpesviruses? Where does assembly take place?

Answer 3

nucleus

Question 4

Alphaherpesviruses have _____ latency

Betaherpesviruses have _____ latency

Answer 4

neurotropic

lymphotropic

Question 5

Important alphaherpesviruses?

Important betaherpesviruses?

Answer 5

VZV

HHV-6 and HHV-7

Question 6

When does herpesvirus latency occur?

Answer 6

soon after initial infection

Question 7

3 stages of herpesvirus latency?

Answer 7

1. Establishment
2. Maintenance
3. Reactivation (lapse in immune status of host)

Question 8

How does the herpesvirus persist in latency?

Answer 8

entire genome is maintained extrachromosomally and few viral genes are expressed, which allows it to remain undetected

**no virus particles produced

Question 9

Primary VZV infection always results in:

How does this progress, in general terms?

Answer 9

chicken pox, regardless of age

1. fever
2. itchy rash starting on scalp, spreading to trunk

Question 10

How are adult primary VZV infections different from those in kids?

Answer 10

Adult cases can be more severe, resulting in pneumonia or pneumonitis (but less rash)

Question 11

When do VZV infections usually occur?

Answer 11

late winter and early spring

Question 12

T/F: Primary VZV has a 50% rate of infection.

Answer 12

F: He said it’s like 96% of people at home who get the effing chicken pox.

Question 13

How is primary VZV spread?

Answer 13

aerosol

Question 14

Pathogenesis of chicken pox:

What occurs during the incubation period?

Answer 14

1. Infection of conjuntivae and/or mucosa of URT
2. Virus replicates in regional lymph nodes, (resulting in primary viremia)
3. Virus replicated in liver/spleen/etc (resulting in secondary viremia)
4. Vesicular rash (~day 14)

Question 15

Describe reactivated VZV?

Answer 15

shingles: sudden onset of pain and rash along either
1. thoracic dermatome
2. forehead (can cause ocular involvement)

Question 16

How long do symptoms from reactivated VZV last?

Answer 16

for 2-4 weeks, but pain can last much longer (postherpetic neuralgia)

Question 17

What kind of vaccine is used to prevent chicken pox? Zoster?

Answer 17

1. attenuated live vaccine
   (note: part of MMR series now)
2. vaccine given to boost immunity
   (may lessen, rather than prevent)

Question 18

How is chicken pox treated in kids? Adults?

Answer 18

treat symptom (itchiness/aches) unless ICH (ACV)

adult pneumonia may require VZV Ig

Question 19

How is zoster treated?

Answer 19

oral ACV + steroids

Question 20

What do HHV-6 and -7 cause?

Answer 20

roseola (exanthem subitum)

Question 21

What are the symptoms of HHV-6 and -7 infection?

Answer 21

1. Mild respiratory illness followed by high fever (as high as 104F)
2. after fever, some have blanching rash on face/body x2-3 days

Question 22

Who do HHV-6/7 infect?

Answer 22

kids 3mo to 6 years old