Herpesviridae Flashcards
what is Herpes structure
double stranded DNA with an envelope
where does replication occur
in nucleus of infected cells
how many herpes visuses
8 - all species specific
where does HSV 1, 2 and VZV stay latent
sensory and cranial nerve ganglia
where does CMV, and HHV 6 stay latent
monocytes, macrophages, CD34 cells
where does HHV- 7 stay latent
CD4
where does EBV stay latent
memory B cells
where does HHV8 stay latent
B cells
what is only HV that can be tranmitted by aerosol
VZV
2 HV that can be transmitted by blood
CMV and HHV 8
how does HV transmit
- not long lived outside
- may be transmitted during symtomatic or asymptomatic stages
what does transmission from primary infection cause in new person
primary infeciton
what does transmission from reactivation cause in new person
primary infectiokn
what percent of people with HSV2 are symptomatic
10-15%
where is most HSV1 and 2
1 - mouth
2 - genitals
what are other locations of HSV 1
cornea, hands, brain (baby)
length of promary infection in HSV
1 - 10-14 days
2 weeks
what is recurrence rate for HSV
- 20-40%
2. - 60-90%
what does HSV serology tell you
- no reliable IgM test
that at some point you had it
2 treatments of HSV
- support
2. antivirals can reduce duration, but must be taken within 72 hours
what make VZV so contagious
infectious for 2 days before crusting
ariborne
lifetime risk of reactivation of VZV
30%
3 syndromes caused by VZV
- chickenpox
- zoster (shingles) - scarring, post-herpetic neuralgia
- congenital - if mom had it in first20 weeks
what are 2 most common dermatomal zoster places
chest and face
4 ways to diagnose VZV
- clinical
- serology for IgG and IgM (Acute)
- direct detection - immunoflourecnces
- isolation - vesicular fluid
treatment of VZV
acyclovir if severe
2 ways to prevent VZV
- VZIg if in 72 hours
2. vaccines for VZ and shingles
what is varicella vaccine
live attenuated vaccine - 95% AB response
what is zoster vaccine
live attenuated virsu - 50% effective
what is HHV 6
common and causes roseola infatum - not serious
what is EBV
most infection asymtomoatic
- spread by sailva
- fever, mal;aise , lymphadeopathy
- associated with burkets lymphoma and pharyngeal carcimona
what is EBV diagnosis
- no culture
- PCR can monitor, but not diagnose
- monospot (heterophile AB) is gold stnadard
what is CMV
acute is ustually asymptomotic
- may be mono-like
- severs seen in AIDS, transplants, neonates
what happens in congential CMV
- Sx in 25%
- cytomegalic inclusion disease
- jaundice, hepatosplenomegaly, petechial rash, microcephaly
what happens in HHV-8
healthy - febrile exanthem
immunocompromise- kaposi sarcoma, castlemans disease
