Maternal immunization is poised to help many more infants survive. One pediatrician-turned-researcher has made this area of medical innovation his life’s work.
When Dr. Shabir Madhi was a young pediatric resident at a hospital in Johannesburg, South Africa, in the mid-1990s, he cared for newborn infants with tetanus at least once a week. Even after he placed them on ventilators, less than 10% of his tiny patients survived. But by the early 2000s, a campaign to vaccinate pregnant women with two doses of a tetanus vaccine had reduced the number of infants who died from tetanus by 90%, from about half a million babies each year to fewer than 50,000.
“Almost overnight, that brought about a complete change in the face of tetanus epidemiology,” says Madhi, a professor of vaccinology at the University of the Witwatersrand in Johannesburg and director of the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit. Now it is rare to see even one case per year of neonatal tetanus at the hospital where he trained.
Stopping “invisible killers” of infants
The potential of maternal immunization—vaccinating a pregnant woman to protect her and her newborn—is clear. “One of the most important aspects of maternal immunization is that it’s addressing what is really emerging to be the major challenge in further reducing deaths in children under the age of 5, where more than 45% of deaths occur in the first month of life,” Madhi says.
Today his work spans research and policy. He is particularly focused on trials to develop maternal vaccines for respiratory syncytial virus (RSV) and group B streptococcus (GBS). These two invisible killers, like tetanus, can affect infants in the earliest hours and weeks of life, before their immune systems can fight back.
RSV and GBS remain understudied, and research funding is still too scarce. In high-income countries, pregnant women are often tested for GBS just before delivery and given antibiotics if needed. In South Africa and other settings with limited public-health resources, that level of diagnostic care is neither affordable nor feasible. Maternal immunization offers the best option to protect both mother and child.
Benefits that ripple outward
Over more than two decades of vaccine research, Madhi and his colleagues have documented important extra benefits of maternal immunization for people with limited access to health care. One study he co-authored found that babies born to pregnant women vaccinated for influenza were 40% less likely to be hospitalized for pneumonia. Researchers have also found a lower incidence of preterm labor among women vaccinated against COVID-19 compared with unvaccinated mothers. Even a modest reduction in preterm labor would have a significant impact on child survival where medical care is hard to reach.
“Maternal immunization is a three-in-one value proposition. It confers protection to the mother, it directly influences the outcome of the pregnancy, and it protects the infant.”Dr. Shabir Madhi
Given the progress Madhi has seen since he struggled to save newborns with tetanus, he has only become more convinced of the power of this tool. “It confers protection to the mother, it directly influences the outcome of the pregnancy, and it protects the infant, especially during the period of time when the child is most vulnerable.”
More on maternal immunization
Return to the series · Why GBS screening is so important · How maternal vaccines save lives