HSV Flashcards
HSV
Types
Transmission routes
HSV-1 Oro-labial. Reduced frequency of recurrence, higher risk of transmission.
HSV-2 Genital. Higher frequency of recurrence, lower risk of transmission.
Transmission: 90% in labour from infected secretions - Most are born to asymptomatic women 5% in utero (trans placental or ascending from cervical lesions) 5-10% post partum
Recurrent HSV
Risks to neonate
Lesions at delivery: 1-3%
No lesions at delivery <1%
Primary HSV
Risks to neonate
If infection <6weeks prior to delivery or no seroconversion: 25-50%
If active lesions at delivery: 50%
If infection >6weeks prior to delivery/1st and 2nd trim: Similar to recurrence
Features of congenital HSV
No clear pattern - high index of suspicion needed
- Fever
- Vesicles
- Lethargy
- Seizures
- DIC
- Sepsis (-ve blood cultures)
- Low plts
- LFT derangement
- Respiratory distress
- Corneal ulcer/keratitis
- Encephalopathy
- Mortality 50-90% if CNS, disseminated, untreated
HSV
Investigations
Genital swab - viral PCR
Serology - type specific IgG
Recurrent HSV
Management
Consider prophylactic antiviral from 36weeks if recurrent episodes in pregnancy
Counsel re risks of transmission
Aim vaginal delivery (or as per obstetric basis)
Careful speculum in labour to assess for lesions
FBS, FSE, ventouse or forceps MAY increase transmission
Primary HSV
Management
Antiviral treatment 1g valaciclovir PO BD 7days
Topial lignocaine
IDUC if retention
ABx if superimposed infection
Consider prophylactic antiviral 500mg valaciclovir PO BD from 36weeks
Counsel re risks of transmission
If 1st/2nd trim - Aim vaginal delivery (or as per obstetric basis)
If 3rd trim - CS recommended
Careful speculum in labour to assess for lesions
Unless clear obstetric indication avoid FBS, FSE, ventouse or forceps as MAY increase transmission
HSV
Prevention
HSV
Management at delivery
