Objectives: To study retrospectively the epidemiology, demography and clinical issues related to varicella in pregnancy in a UK city over a 5-year period and help inform the debate on the potential of varicella immunisation in prevention.
Methods: The hospital records of pregnant women with varicella receiving care at the Regional Department of Infection and Tropical Medicine in Sheffield between 1997 and 2002 were reviewed. Data on pregnant women with varicella not presenting acutely to medical care were obtained. The use of Varicella Zoster Immune Globulin (VZIG) in prevention of varicella during the same 5-year period was determined. The records from the maternity department of Sheffield Hospitals for women undergoing VZV antibody testing between January and December 2004 were reviewed. Data on annual number of deliveries were recorded and the neonatology database used as a source of information regarding effects of chickenpox on the baby.
Results: The incidence of varicella infection in pregnancy was at least 6 per 10,000 deliveries. Nineteen pregnant women with varicella were admitted to hospital. Three had pneumonia. Infection occurred in the first pregnancy in a quarter of cases. The minimum cost for all cases admitted to hospital during this period (basic costs per day) was 20,520 pounds sterling. The cost of VZIG use for chickenpox during the same period adjusted for the population size was 10,881 pounds sterling. This was not a comprehensive health economic study and did not attempt to assess additional GP, midwifery, obstetric or social costs nor costs associated with those who did not attend hospital. Two hundred and thirty-three women underwent VZV antibody test during 2004 usually after contact with chickenpox. Sixty percent of women in contact with chickenpox did not present to their GP or hospital immediately.
Conclusion: Varicella in pregnancy may be associated with significant morbidity and health care cost and prevention by immunisation is desirable. Though targeted vaccination is attractive, screening in pregnancy followed by a post-partum varicella immunisation programme would fail to protect 25% and would be associated with logistical challenges not occurring with rubella immunisation. Varicella is now a preventable disease by immunisation. Exposure in pregnancy with or without infection has financial costs related to antibody testing and prophylaxis. Infection in pregnancy may be associated with additional costs and potential morbidity to mother and baby. Potential immunisation strategies are considered.