Streptococcal sore throats (pharyngitis) are especially common among school-aged children and teenagers. These include: GBS infection in a previous baby Labor or waters breaking (rupture of membranes) before 37 weeks (preterm) Rupture of membranes18 hours or longer before delivery of a full-term pregnancy Fever during labor If you carry group B strep bacteria, your baby can become infected during a vaginal delivery. The short answer is that babies rarely need to be treated for strep throat. The most common infection caused by group A streptococci is a sore throat known as strep throat. In children over the age of 3, the bacteria that causes strep throat can cause significant complications if untreated. Group A streptococcal (GAS) organisms are also responsible for skin infections, including some cases of impetigo and cellulitis. Not every baby who is exposed to GBS will get infected, but a small percentage can It’s more likely if: The bacteria can cause trouble in a child's kidneys, skin, and heart—the infection should not be missed!