PATH welcomes grant to advance Group B Streptococcus vaccine development

PATH has received a five-year, $29.3 million grant from the Bill & Melinda Gates Foundation to support the development of a vaccine against Group B Streptococcus (GBS), a leading cause of sepsis and meningitis in young infants worldwide. A vaccine to prevent the bacterial infection—which often affects babies just a few hours old—could potentially save countless lives in the low-resource countries most impacted by the disease. Grant funds will support the research and development of a polyvalent, conjugate vaccine protecting against the most common kinds (or serotypes) of GBS.

Although people of any age can contract the bacterial infection (caused by Streptococcus agalactiae), infants under three months of age are at highest risk of severe complications and death. Moreover, babies who survive the disease are often left with lifelong disabilities such as deafness, blindness, and developmental delays. GBS may also play a role in miscarriage and stillbirth.

No licensed vaccines currently exist to protect against GBS, creating a distinct vulnerability in parts of the world where early testing of pregnant women for carriage of GBS and preventative antibiotic treatment are not readily feasible. In some high-resource countries, women who test positive for carrying the GBS bacterium at 35 to 37 weeks of pregnancy receive intravenous antibiotics during labor, drastically reducing the chances of GBS passing to the newborn and causing early-onset disease. In low-resource countries, however, GBS screenings are all too often unavailable for women, which means mothers are unlikely to receive preventative antibiotic treatment during labor. Moreover, babies born healthy can contract the disease in the weeks or months following birth without any clear cause—cases where maternal antibiotic prevention is of little help.

A safe, effective, and affordable vaccine against GBS delivered to pregnant women could help to eliminate the chance of newborn infection and provide babies with the critical protection they need to survive infancy. Such a vaccine will be an important tool in the maternal immunization toolkit—a promising way to prevent disease in pregnancy and the newborn period. By vaccinating a woman during pregnancy, it's possible to boost her immunity and naturally transfer antibodies through the placenta to her developing fetus. The approach has demonstrated success in combatting maternal and newborn tetanus, influenza, and pertussis around the world. Efforts to develop a GBS vaccine designed for low-resource countries represent continued support and investment in maternal immunization strategies and a chance for all babies to get a healthy start in life.

Posted January 12, 2017.