Group B streptococcus is one of the biggest killers of newborns in both wealthy and disadvantaged countries alike; now we are closer to a vaccine that could save thousands of lives every year.
In many people, Streptococcus agalactiae or Group B streptococcus (GBS) is a roundish bacterium drifting along in chains through our body, part of the microbiome of bacteria that co-exists harmlessly inside us, including in around 1 in 5 pregnant people.
However, in babies, both in the womb and outside, this mostly benign bacterium can turn deadly, causing pre-term births or stillbirths.
Even when newborns survive the birth, they can still become very ill with meningitis (when the meninges (the thin lining covering the brain and spinal cord) become infected), or sepsis (blood poisoning, which can trigger tissue damage, organ failure, and death).
GBS can also cause pneumonia, which kills more children each year than any other disease, causing pre-term births, stillbirths, and neonatal deaths.
Group B streptococcus disease
The bacteria has 10 different serotypes, with 1a, 1b, II, III, IV, and V causing the most disease. According to the World Health Organization, GBS was estimated to have caused 392,000 cases of neonatal disease annually in 2015, causing 91,000 deaths and at least 57,000 stillbirths. Africa by far bears the highest burden, as it has 54% of estimated invasive GBS cases, and 65% of all infant deaths.
While the biggest risk is to babies, it can also affect elderly people or those who are immuno-compromised.
As there is no licensed vaccine yet, in high-resource countries, pregnant people are screened for GBS colonization and given prophylactic antibiotics (penicillin). This is more than 80% effective for preventing early-onset disease in infants (up to six days of age) but not against late-onset disease (7 to 89 days) or prebirth sequelae associated with GBS infection.
This article originally appeared on gavi.org.
