Streptococcus B Testing in Pregnancy (GBS Testing). Streptococcus B infection is the most common cause of infection in newborns in the first three months of life. Early onset occurs within the first week of birth and has the potential to cause serious infection such as sepsis, pneumonia or meningitis. A later onset of the disease occurs between 7-89 days of age and can cause similar illness to the early onset GBS, but it tends to be more commonly meningitis. The World Healt
