Varicella Zoster/Chickenpox

Question 1

Define VZV infection in pregnancy.

Answer 1

Primary infection with VZV.

Question 2

Explain the aetiology of VZV in pregnancy.

Answer 2

Transmitted by physical contact, aerosol, vertical transmission

Question 3

What are the risk factors for VZV in pregnancy?

Answer 3

No prior immunity, contact, immigration from tropical/subtropical areas.

Question 4

Summarise the epidemiology of VZV in pregnancy.

Answer 4

3/1000 pregnancies.

Question 5

What are the symptoms of VZV in pregnancy?

Answer 5

Fever

Malaise

Pruritic rash (vescicular then crusts over)

Question 6

What are the signs of VZV in pregnancy?

Answer 6

Vescicular pleiomorphic rash

Question 7

What investigations would you do for VZV in pregnancy?

Answer 7

Blood: VZV IgM in the acute phase, IgG to check immunity.

USS: Fetal antenatal anomaly scan (fetal varicella syndrome)

Question 8

What is the management for VZV in pregnancy?

Answer 8

Non immune mother: VZVIG (reduces chance by 50% after exposure)

Established VZV: Aciclovir, if within 24h of rash onset.

Maternal infection near term: Avoid elective delivery for 5-7 days from the appearance of rash (placental transfer of maternal Ab over 5-7d)

Neonate: VZVIG if delivered within 7d of rash onset, before or after.

Question 9

What are the complications associated with VZV in pregnancy? What is the prognosis of VZV in pregnancy?

Answer 9

Maternal pneumonia (10%, only in prengnat women!), hepatitis, encephalitis, death.

Fetal varicella syndrome: If maternal infection before 28wk, skin scar, eye defects, neuro defects, limb deformities.

Neonatal: VZV infection in the newborn (if maternal infection 1-4wk before delivery to 1wk after.