Group B streptococcal disease

Group B Streptococcal Disease (GBS), also known as Group B Streptococcus infection, is a type of bacterial infection caused by the bacterium Streptococcus agalactiae. This bacterium is commonly found in the human body, particularly in the gastrointestinal and genitourinary tracts, and does not always cause illness. However, it can lead to serious infections in certain populations, including newborns, pregnant women, and adults with certain chronic medical conditions.

Causes and Transmission

Group B Streptococcus can colonize the gastrointestinal tract, vagina, and rectum of healthy individuals without causing symptoms, a condition known as asymptomatic carriage. The main risk of transmission is from mother to newborn during childbirth. Pregnant women who are colonized with GBS can pass the bacteria to their babies during delivery, leading to early-onset disease in newborns, which occurs in the first week of life. Less commonly, GBS can cause late-onset disease in infants, occurring from one week to several months after birth.

Symptoms and Diagnosis

In newborns, GBS infection can lead to sepsis, pneumonia, and meningitis, presenting with symptoms such as fever, difficulty feeding, irritability, and lethargy. In adults, GBS can cause urinary tract infections, skin and soft-tissue infections, bloodstream infections, and pneumonia.

Diagnosis of GBS infection involves the culture of body fluids, such as blood or cerebrospinal fluid, to detect the presence of the bacteria. Pregnant women are typically screened for GBS colonization during the third trimester of pregnancy to assess the risk of transmitting the bacteria to the newborn.

Prevention and Treatment

Prevention of early-onset GBS disease in newborns is primarily achieved through the intrapartum administration of antibiotic prophylaxis to GBS-colonized pregnant women. This approach has significantly reduced the incidence of early-onset GBS disease.

Treatment of GBS infection involves the use of antibiotics. Penicillin is the antibiotic of choice for both the prevention of transmission from mother to child and the treatment of GBS infections in newborns and adults.

Epidemiology

Group B Streptococcus is a leading cause of neonatal sepsis and meningitis in many parts of the world. The implementation of guidelines for the screening of pregnant women and the use of intrapartum antibiotic prophylaxis has led to a significant decrease in the incidence of early-onset GBS disease in newborns.

Public Health and Research

Ongoing research is focused on the development of vaccines against GBS to prevent colonization in pregnant women and the subsequent risk of transmission to newborns. Public health efforts continue to emphasize the importance of screening and preventive measures to reduce the burden of GBS disease.