HSV + VZV Flashcards
Kaposi sarcoma is caused by …
HHV8
Which herpes viruses set up latent infection in sensory nerve ganglia?
1,2,3
HHV 5, 4 and 8 set up latent infection in
B lymphocytes
HHV5 and 4 set up latent infection in
Epithelial cells
HHV6 and 7 set up latent infection in
T lymphocytes
HHV 4 sets up latent infection in
both epithelial cells and B lymphocytes
Alphaherpes viruses
HSV and VZV
Rapid growth in cell culture
neuronal latency
Betaherpes viruses
CMV, HHV6A and B
slow growth
affinity for CD4 lymphocytes
Gammaaherpes Viruses
EBV
only grow in lymphoblastoid cell lines
affinity for B lymphocytes
Structure of herpes viruses
Lipid envelope
icosahedral capside
dsDNA
Genital herpes is classically associated with
HSV2
Rates of seropositivity to HSV is highest in
crowded, disadvantaged, lower SEG
What is the primary route of HSV1 transmission
oral secretions from individual actively shedding virus
What impact fro congenital deficiencies in humeral immunity have on HSV1 infection?
not a significant risk factor for serious HSV disease
Impact of deficient cell-mediated immunity on HSV infection?
Congenital + acquired deficiencies in cell mediated immunity ARE associated with severe HSV disease
What is the most common presentation of HSV1
Gingivostomatitis
typical location of HSV1 encephalitis
fronts-temporal and parietal regions
Pneumonitis and hepatitis are common presentation of HSV1 recurrence in
Neonates
How does recurrence of HSV1 manifest in immunocompetent individuals
asymptomatic shedding
herpes labialis
keratoconjunctivitis
rare - encephalitis
When is an antiviral most effective for HSV1?
within 72hrs of infection starting
How doe the majority of HSV2 infections present?
majority are clinically silent
T or F HSV1 infection prevents aquisition of HSV2
F
does not present but does reduce the likelihood of
are males or females more easily infected with HSV2
FEMALES
what is the main risk factor for infection of HSV2
no of sexual partners
are genital lesions of HSV usually uni or bilateral?
Bilateral
What babies are most at risk of acquiring congenital HSV infection?
Baby born to mother that was seronegative and develops genital herpes in the 3rd trimester
what proportion of patients with a primary HSV2 infection report recurrence?
60%
VZV peak
spring
Peak age of primary infection of VZV
kids <5yrs
where is the site of replication + spread of VZV
replicated in nasopharyngeal lymphoid tissue and spreads to RES
What part of the skin is infected by VZV
isthmus of hair follicles
rich in stem cells
IP of VZV
7-23 days
shorter in immunocompromised
what is characteristic of a VZV rash
centripetal
starts peripherally and moves to trunk
When are patients with VZV infectious
from 2 days before rash until the vesicles have crusted and no new vesicles are forming
What is the most common complication of VZV
secondary bacterial infection
is viral pneumonia after VZV more common in adults or kids
adults
esp in smokers, pregnant women
also children with leukaemia
baby with skin scarring, limb hypoplasia and CNS defects is typically caused by
congenital varicella syndrome - infection occurred early, in the 1st trimester
What is the most common complication of Zoster
Post-herpetic neuralgia
- pain lasting >4wks after rash onset
What is the effectiveness fo antiviral use for ZAP
reduce the incidence, duration and severity of ZAPain if started within 3 days of rash onset
