BALTIMORE — Group B Streptococcus infection may cause almost 150,000 stillbirths and infant deaths each year globally, according to research presented at the annual American Society of Tropical Medicine and Hygiene meeting.
As an alternative to antibiotics, vaccines in development could prevent many group B Streptococcus (GBS) cases, researcher Anna C. Seale, BMBCh, PhD, an associate professor at the London School of Hygiene & Tropical Medicine, said at the meeting.
“Even if antibiotics were given to all pregnant women identified through screening strategies, they target mainly early-onset GBS disease in newborns, not GBS disease in pregnant women, GBS disease before delivery causing stillbirth, or GBS disease in infants more than a couple of days old,” she said in a news release. “A maternal GBS vaccine could prevent many more cases and deaths worldwide.”
Seale and colleagues conducted 11 studies on GBS. They reviewed data on the global prevalence of GBS colonization in pregnant women, the risk for infant disease associated with it, antibiotic prophylaxis policies, stillbirths, infant deaths and maternal disease.
The researchers estimated the global burden of GBS, along with associated morbidity and mortality. They included births in 195 countries in 2015.
Results of their analysis, which were also published in Clinical Infectious Diseases, showed that the United States had the fourth highest estimated number of pregnant women colonized with GBS, at 942,800. Only India, China and Nigeria had more, with almost 2.5 million, 1.9 million and 1.06 million, respectively.
The researchers estimated that there were 319,000 infants aged younger than 3 months with GBS disease worldwide in 2015. Among those cases, about 90,000 deaths occurred, as well as 57,000 stillbirths, they said.
Without antibiotic prophylaxis, the researchers said, a maternal GBS vaccine that is 80% effective and covers 90% of pregnant women would prevent about 231,000 GBS cases in women and infants each year. The vaccine would also prevent about 41,000 stillbirths and 66,000 infant deaths each year, they added.
Seale and colleagues further estimated that a pentavalent vaccine would prevent 86% of early-onset GBS and 93% of late-onset GBS, as well as 97% of maternal GBS.
Researcher Johan Vekemans, MD, PhD, medical officer of the WHO Initiative for Vaccine Research, said officials must hasten vaccine development.
“It is now essential to accelerate the GBS vaccine development activities,” he said in the release. “The technical feasibility is estimated to be high … Work is ongoing to strengthen existing maternal immunization programs. Next steps include a comprehensive evaluation of cost-effectiveness.” – by Joe Green
Seale AC, et al. Clin Infect Dis. 2017;doi:10.1093/cid/cix657.
Disclosures: Seale reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.