Group B streptococcal infection
Group B streptococcal infection is also known as Group B strep infection. This is an overgrowth of the bacteria, Streptococcus agalactiae, in the vaginal canal. Group B strep is a common bacterium often found in the intestines and rectum, but also in some women, it can be present at low amounts in the vaginal canal.
The bacterium is usually harmless in healthy adults, and causes no symptoms. However, it can cause a serious illness known as ‘Group B Strep’ (GBS) disease in newborns. It may also cause serious infection in an elderly person if they are already immunocompromised.
In mothers who carry Group B strep, its been found to cause serious illness in 1 in 1750 pregnancies.1 Group B strep is the most common cause of life-threatening infection in newborn babies in the UK, and of meningitis in babies under age 3 months.2 There is an extremely small risk of miscarrying or losing a baby in cases of Group B strep.
For this reason, some healthcare providers screen for Group B strep in pregnant women. It is advised to carry out a swab within the last 5 weeks of pregnancy, given its transient nature.2 If Group B strep is found to be present during the later stages of pregnancy, antibiotics may be administered to the mother during labour, to reduce the chances of transmission to the newborn.
References
- NHS. Group B strep. Available at: https://www.nhs.uk/conditions/group-b-strep/. Accessed Mar 12, 2025.
- Group B Strep Support Group. Information and SupportAvailable at: https://gbss.org.uk. Accessed Mar 12, 2025.
