What causes streptococcus B?
Group B streptococcus (GBS) is the most common cause of life-threatening infections in newborn babies in the UK. GBS infects about 700 babies each year and kills around one in eight. Most of these infections could be prevented, yet awareness is low. What is GBS? GBS is a bacterial infection. It is not a sexually transmitted disease. Although up to a third of all men and women carry the bacteria in their intestines it rarely causes GBS infection, or side effects. GBS is generally only a problem for newborn babies. More rarely it can cause infection in adults, typically women during pregnancy or after birth, the elderly and people with serious underlying medical conditions which impair their immune system. What problems can it cause? If a pregnant woman is infected with GBS, there is a chance she could pass it to your unborn baby. Most babies will not be harmed if their mother is infected, but GBS can cause early birth, stillbirth, late miscarriage and complications. Roughly a quarter of
Group B strep bacteria are different from many other types of bacteria that can cause disease. People can be “colonized” with group B strep. This means that they carry the bacteria in their bodies but are not infected and do not become sick. Adults can carry the bacteria in the gastrointestinal tract, genital tract, or urinary tract. About 10% to 30% of pregnant women are colonized with group B strep in the genital tract. Colonization with group B strep is usually harmless. The bacteria can become deadly, though, if something happens that allows them to invade the bloodstream. In adults, weakened immunity resulting from cancer treatment or a chronic illness can prompt an infection. More often, pregnant women who carry the bacteria can unknowingly transmit group B strep to their newborns at birth. Newborns can acquire early-onset group B strep disease either before or during delivery. The cause of late-onset disease in babies is not well understood.
