2015 13 Chicken Pox In Pregnancy Flashcards
** Can women be immunised against varicella? **
- If seronegative, can immunise pre-pregnancy or postpartum
- Universal antenatal testing not recommended
- Safe to breastfeed with vaccine
** What measures are taken in relation to varicella at the booking visit? **
- Ask all about previous infection or vaccination
- If no hx, advise to avoid contact with disease & seek HC ASAP if exposed
** How can infection be prevented if a woman has contact with varicella? **
- Careful history
- Test for immunity if uncertain hx
- Aciclovir or valciclovir day 7-14 post-exposure if significant & non-immune
- VZIg if antivirals contraindicated or adverse effects, up to 10d after contact
** For how long is a non-immune pregnant woman exposed to chicken pox seen as infectious? **
- 8-28 days post-exposure if receive VZIg
- 8-21 days post-exposure if they don’t
** When is varicella PEP repeated? **
- Further exposure with no seroconversion
- Antivirals: 7 days from exposure
- VZIg: if exposure 3 weeks or more after last dose
** What are the risks of varicella infection as an adult? **
- Pneumonia
- Hepatitis
- Encephalitis
** What infection control measures should a pregnant woman with chicken pox take? **
- Immediately contact GP
- Avoid contact with other pregnant women & neonates until lesions crusted over
- Symptomatic treatment & hygiene to prevent secondary bacterial infection
** What is the treatment for chicken pox in pregnancy? **
- Oral Aciclovir if present within 24 hours of rash onset, esp if >24/40
- IV Aciclovir to all severe cases
- No VZIg as no benefit once developed
** When should pregnant women with chicken pox be referred to hospital? **
- Respiratory symptoms
- Other deterioration
- If at high risk of severe or complicated disease
** When & how should women with chicken pox give birth? **
- Individualised timing & mode
- For planned birth, ideally 7 days after onset to allow passive antibody transfer
- For epidural or spinal, need site away from cutaneous lesions
** What are the risks to the fetus of varicella infection in pregnancy? **
- No increased risk of 1st trimester spontaneous miscarriage
- Fetal varicella syndrome if within first 28/40
- Neonatal infection if within last 4/40 of pregnancy
** Can fetal varicella infection be diagnosed antenatally? **
- FMU referral at 16-20/40 or 5 weeks after infection
- Discussion & detailed USS
- Amniocentesis strong NPV but poor PPV, so careful consideration
** What are the neonatal considerations with varicella infection pregnancy? **
- Infection risk, esp last 4/40
- Inform neonatologist of infection at any gestation
- Breastfeeding is safe
What type of virus is VZV?
DNA virus
Human herpesvirus 3
How is VZV transmitted?
Respiratory droplets
Direct contact with vesicle fluid
Via fomites
