Vaccination of pregnant women against whooping cough has been shown to provide newborns with early immune protection, according to research led by Radboud university medical center. The study found that antibodies generated by the vaccination are transferred from mother to child not only through the blood but also reach the nasal mucosa, which is where whooping cough bacteria typically enter the body.
Dimitri Diavatopoulos, an immunologist at Radboudumc, explained, "We give this vaccine to protect babies from whooping cough right after birth. In the first weeks of life, babies are extremely vulnerable and too young to be vaccinated themselves. That's why we vaccinate the mother during pregnancy." He added that while it was already known that maternal antibodies could be passed through the placenta, "This study now shows that these antibodies also reach the nasal mucosa – exactly where whooping cough bacteria enter the body."
The research involved 343 mothers and their infants in a collaboration between Radboudumc and the Medical Research Council Unit The Gambia. Half of the participating pregnant women received a pertussis vaccine. According to Diavatopoulos, "Mothers who were vaccinated during pregnancy passed on antibodies through the placenta that were subsequently detected in the baby's nasal mucosa."
The study also compared two types of vaccines given to infants: whole-cell and acellular pertussis vaccines. Babies receiving three doses of a whole-cell vaccine developed a stronger immune response than those given an acellular version. Diavatopoulos described, "The difference is that a whole-cell vaccine contains the complete, but inactivated, whooping cough bacterium, whereas an acellular vaccine contains only a few purified components of the bacterium." Janeri Fröberg, postdoctoral researcher at Radboudumc stated, "Acellular vaccines usually cause fewer side effects but often also provide shorter-lasting protection. Our findings suggest that whole-cell vaccines may support longer-term immune protection."
Since 2005, most European countries have used acellular vaccines for pertussis immunization; however, many low- and middle-income countries continue using whole-cell vaccines due to cost and availability factors.
Researchers stressed that further investigation is needed to assess how these findings might affect clinical outcomes and inform vaccination policies globally.
For countries like the Netherlands offering maternal vaccination at 22 weeks gestation—known as the 22-week shot—the results reinforce its value in protecting infants during their highest risk period immediately after birth. In lower-income regions where infant mortality from pertussis remains high due to limited access to effective vaccines each year—estimated between 200,000 and 300,000 deaths worldwide—the implementation of maternal vaccination programs could reduce fatalities significantly.
Additionally, for nations still administering whole-cell vaccines for primary immunization series in infancy, these results support continued adherence to World Health Organization (WHO) guidance recommending their use because they may offer more durable immunity.
