Herpesviridae Virology

Question 1

What is Herpesviridae?

Answer 1

dsDNA virus with an envelope; 8 herpesviruses known

*replication in nucleus of infected cell (episomal ie DNA not incorporated to host genome)

Question 2

What two types of infection do herpes viruses cause?

Answer 2

lytic and latent infection

Question 3

What cells are infected by the following members of the herpesviridae family?

HSV 1,2, VZV
CMV, HHV6
HHV-7
EBV
HHV-8

Answer 3

HSV 1,2, VZV: sensory and cranial nerve ganglia

CMV, HHV6: monocytes, macrophages, CD34+ cells

HHV-7: CD4+ cells (helper)

EBV: Memory B cells (mono)

HHV-8: B cells

Question 4

What are precipitating factors for herpes reactivation?

Answer 4

sunlight
fever
local trauma
menstruation 
emotional stress

Question 5

What antivirals are used to treat Herpes?

Answer 5

acyclovir, famiclovir, valacyclovir

*impact shedding and duration of sores

Question 6

What 3 conditions are a result of infection with VZV?

Answer 6

• chickenpox
• Zoster (shingles)
• Congenital Varicella (v uncommon)

Question 7

What is the rx for VZV?

Answer 7

• if chickenpox in healthy kid, nothing

- severe disease in immune compromised people: acyclovir

Question 8

What are the preventative measures for VZV infection?

Answer 8

-VZIG (immune globulin, 96 hrs pre-exposure at least)

• Varicella (chickenpox) vacine.
• Zoster (shingles) vaccine- to keep latent

Question 9

What condition does HHV-6 cause?

Answer 9

Roseola infantum: fever 3-4 d, resolves then get rash

often Asx

Question 10

What disease does EBV cause most often?

Answer 10

• in childhood mostly Asx
• Mono in adultes/teens: fever, lymphadenopathy, fatigue, sore throat, hepatosplenomegaly, atypical lymphocytes
• associated with ‘Burkitt’s Lymphoma’ AND nasopharyngeal carcinoma

**oncovirus

Question 11

How is EBV infection diagnosed and treated?

Answer 11

• Monospot (heterophile Ab) SEROLOGY

- supportive rx, protect spleen, no vaccine

Question 12

What disease does CMV cause?

Answer 12

• mono-like illness, hepatitis, Asx (usually)

- severe illness in : AIDS, Tx, Neonates

Question 13

What condition cause CMV cause in neonates?

Answer 13

CID- cytomegalic inclusion disease : jaundice, hepatosplenomegaly, petechial rash, microcephaly, cerebral calcifications, chorioretinitis

Question 14

Who is treated for CMV and what is the treatment of choice?

Answer 14

only immunocompromised patients are treated for CMV inection.

Ganciclovir, Foscarnet

Question 15

What is the alternative name for HHV-8?

Answer 15

Kaposi’s Sarcoma-Associated Herpesvirus (KSHV)

Question 16

What does HHV-8 infection cause in healthy versus immunocompromised people?

Answer 16

healthy: febrile exanthem, mono?

immune compromised: Kaposi’s sarcoma, Castleman’s disease, Primary effusion lymphoma

Question 17

How is Kaposi’s Sarcoma diagnosed?

Answer 17

-skin lesion biopsy…

usually seen in HIV positive individuals (90-100% KS in HIV+)