Varicella Flashcards
If exposure to VZV
Check serology urgently (96 hours to process
Exposure <96 hours - ZIG
Exposure > 96 hours - aciclovir
Infectious phase
2 days before rash until lesion crusted
Aciclovir PEP
800mg PO 5x daily
Complications of VZV
Respiratory symptoms Haemorrhagic rash or bleeding New pocks developing > 6 days Persistent fever > 6 days Neurological symptoms
Risk of fetal varicella syndrome by gestation
<12/40: 0.55%
12-28: 1.4%
>28: nil cases reported
Fetal varicella syndrome manifestations
Skin scars Eye abnormalities Limb abnormalities Prematurity, LBW Coritical atrophy, Mental retardation Poor sphincter control Early death
Treatment of infant by timing of delivery
> 7 days: No zig required unless baby is very preterm (<28/40, 1000kg)
<7 days before delivery or 2 days after: ZIG
2-28 days after delivery: ZIG
Pregnant 12/40, expose to child with chicken pox today
Check vaccination and infection history and test immunity if no good hx of infection. Give ZIG if non immune/non vaccinated.
Significant contact
5min face to face, 1hour same room, or family contact
Congenital varicella confirmation
IgM at birth
Treatment if no immunity to varicella
VZIG if <96 hours, can give up to ten days
Aciclovir if >96 hours in at risk cases (seocond half of pregnancy, immunocompromised, smoker, CLD)
Maternal risk
Pneumonia, hepatitis, encephalitis
Death
Mortality rate 0-14%
Oral aciclovir if <24 hours since onset of rash
Risk of timin of infection in pregnancy -FVS
<12 weeks ).55%
12-28 weeks 1.4%
>28 weeks - no FVS reported
Management pregnancy
Review w USSS at least 5 weeks after infection
Discuss amnio - high negative predictive value —-discuss TOP
If any abnormalities - fetal MRI
No case of FVS reported in recent series when amniotic fluid VZV PCR negative
Late growth scan if all negative
Perinatal management
7 days before to 2 days after delivery, VZIG, no isolation and BF encourages
If delivered >7 days and preterm infant <28 weeks and <1000gm - VZIG otherwise no VZIG, BF encouraged
