Pertussis vaccination during pregnancy: long term effects in children and pregnant women.

Despite successful universal pertussis vaccination programs, the disease remains an important public health problem and is nowadays still one of the most common vaccine-preventable diseases in the world. The highest incidence and disease burden can be found in infants below one year of age, too young to be completely protected by the available vaccines and vaccinations schedules. To better protect these infants, maternal pertussis vaccination has been introduced in a number of countries, including Belgium.Scientific evidence on several aspects of this vaccination strategy has boomed over the last years. However, some aspects of this vaccination strategy such as the long-term effect of the strategy on the infant's immune system and the recommended time frame between repeat booster Tdap vaccinations in successive pregnancies have never been investigated. To fill these knowledge gaps, we will look at the humoral immune response in children from mothers vaccinated with Tdap during pregnancy compared to children from unvaccinated mothers before and after a booster dose with a tetravalent aP containing vaccine in the first year of primary school. Also, we will look at antibody concentrations in mothers at delivery and cord blood upon a subsequent delivery. Results from these laboratory tests will feed a mathematical model to describe kinetics of antibodies in children in the presence and absence of maternal antibodies and will help us to make a recommendation on the recommended time frame between repeat booster Tdap vaccinations to have sufficient maternal antibodies at a next delivery. The present proposal will enable fine-tuning of the maternal vaccinations recommendations and existing booster policies in children after maternal vaccination.

Keywords:VACCINOLOGY, PREGNANCY, PERTUSSIS, PERTUSSIS ANTIBODIES

Disciplines:Preventive medicine