Report Emphasizes Need for Group B Streptococcus Vaccine

A recent report from the World Health Organization (WHO) along with the London School of Hygiene & Tropical Medicine (LSHTM) highlights the need for a maternal vaccine against Group B streptococcus (GBS). The researchers said the global impact of GBS causes approximately 150,000 deaths of babies each year, as well as more than a half-million preterm births and significant long-term disability.

The WHO and LSHTM report emphasized the need for a vaccine to lower the impact of GBS, which they noted would be highly cost-effective and have significant health benefits worldwide.

“This new research shows that Group B strep is a major and underappreciated threat to newborn survival and wellbeing, bringing devastating impacts for so many families globally. WHO joins partners in calling for urgent development of a maternal GBS vaccine, which would have profound benefits in countries worldwide,” one of the report’s authors, Dr Phillipp Lambach, medical officer from WHO’s Immunization, Vaccines and Biologicals department, said in a press release.

The report quantifies for the first time how GBS contributes to preterm births, in addition to its role in neurological impairments, such as cerebral palsy, hearing and vision loss, which can follow GBS-associated infections, according to the authors. They added that there have been multiple GBS vaccine candidates in the developmental pipeline for several decades, none of which have been approved.

The report urges for research efforts to accelerate the development of an effective GBS vaccine that could be administered to pregnant women during routine check-ups. They estimated that if GBS vaccination exceeded 70% among pregnant women, more than 50,000 GBS-related deaths could be avoided each year, in addition to more than 170,000 preterm births. The estimated cost savings from a year of maternal GBS vaccination could reach up to approximately $17 billion accrued over several years—if the vaccines are affordable, according to the report.

“Group B strep infection poses a serious challenge to every family affected, and in every country,” professor Joy Lawn, director of the Maternal Adolescent Reproductive & Child Health Centre at LSHTM, who contributed to the report, said in a press release. “Maternal vaccination could save the lives of hundreds of thousands of babies in the years to come, yet 30 years since this was first proposed, the world has not delivered a vaccine. Now is the time to act to protect the world’s most vulnerable citizens with a GBS vaccine.”

The report noted that on average, 15% of all pregnant women worldwide, which is approximately 20 million annually, carry the GBS bacterium in their vagina, typically without experiencing symptoms. The bacteria can then spread to an unborn baby in the womb or to newborns during labor, according to the report.

Antibiotic prophylaxis administered to women during labor is the primary method of preventing GBS disease in newborn infants if it is detected during pregnancy. But even in regions with high prophylactic coverage, there are still significant health risks because the intervention is unlikely to prevent most GBS-associated stillbirths, preterm births, or GBS disease that occurs after birth, the authors wrote.

The report also noted vital gaps in data that cause uncertainty regarding the total burden of deaths and disease caused by GBS. For example, infectious causes of stillbirths are frequently under-investigated across countries, which means the impact of GBS may be higher than what has been reported.

“A new maternal vaccine against GBS would be a game-changer in the reduction of newborn and maternal deaths for the most affected countries, especially sub-Saharan Africa where the burden of these deaths is alarming. We plead to all stakeholders to treat this as a matter of moral priority,” report contributor Dr Martina Lukong Baye, coordinator of the National Multisector Programme to Combat Maternal, Newborn & Child Mortality at the Ministry of Public Health in Cameroon, said in a press release.