Acellular pertussis vaccination in pregnancy: the impact of timing of vaccination on antibody response in infants
BACKGROUND: Whooping cough is a highly contagious respiratory infection which causes significant illness and death, particularly in young children. Vaccinating women against whooping cough during pregnancy increases the amount of antibody in the infant at birth and is effective in protecting the infant from whooping cough before they have received their own vaccines. GAP: Whilst it is now clear that vaccinating women against whooping cough in pregnancy protects infants from disease in early life there is continued debate about what timing of this vaccination would provide the best protection to the infant. HYPOTHESIS: We hypothesise that the vaccination of pregnant women at any time between 20 and 32 weeks of gestational age will result in equivalent concentrations of whooping cough specific antibodies in the infant at birth. METHODS: We will recruit 354 women from 5 UK centres who will be randomized to receive the whooping cough vaccine in one of three groups: <23+6 gestational weeks, 24-27+6 gestational weeks or 28-31+6 gestational weeks. A blood sample will be taken prior to vaccination, at two weeks following vaccination, at the time of delivery from the mother and the cord, and from the infant one month after completion of the primary vaccinations. RESULTS: Pending. IMPACT: Whooping cough vaccination in pregnancy has been shown to protect infants, but it is important that this is offered at a time which provides the best protection to all infants. This study will inform not only policy for whooping cough vaccination, but also has implications for other vaccinations offered in pregnancy with the potential to improve the health outcomes for many children.