Every year, approximately 100,000 newborn babies die from infections caused by a common bacteria that spreads during childbirth. Most of these deaths happen in Africa and other low-income regions, where hospitals and doctors are hardest to reach. Now, researchers in Johannesburg, South Africa, are part of a breakthrough that could change that number — for good.
Scientists at the University of the Witwatersrand, working with the pharmaceutical company Pfizer, have completed an early-stage clinical trial of a new vaccine designed to be given to pregnant women. The vaccine would protect mothers from a bacteria called Group B Streptococcus (GBS) and then pass those protective antibodies to their babies through the placenta — shielding newborns during the most dangerous first months of life.
The trial enrolled pregnant women and their infants, with South Africa contributing the overwhelming majority of participants. The results, published in the journal Nature Medicine, found that the vaccine was safe and triggered strong immune responses against all six strains of GBS it targets. Even better, the antibodies from vaccinated mothers crossed the placenta efficiently, giving newborns high levels of protection at birth.
"Maternal immunization offers the opportunity to protect newborns during the most vulnerable first months of life, when they are at greatest risk of severe infection," said Shabir Madhi, director of the Wits Vaccines and Infectious Diseases Analytics (VIDA) Research Unit and one of the study's senior investigators. "These encouraging findings provide further evidence supporting continued development of this vaccine."
GBS causes sepsis, meningitis, and pneumonia in newborns. In South Africa alone, roughly 2 to 3 out of every 1,000 babies born develop serious GBS infections — one of the highest rates in the world. Current prevention methods involve giving antibiotics to mothers during labor, but this approach has major limitations in rural and under-resourced areas. The World Health Organization has classified a maternal GBS vaccine as a top priority for development.
The Wits VIDA team has now been trusted to lead the next phase of research. A larger phase 3 trial is currently enrolling participants to confirm these promising results. If successful, the vaccine could become a routine part of prenatal care worldwide — potentially saving tens of thousands of young lives every year.