Streptococcus agalactiae also known as Group B Streptococcus (cocci) is a gram-positive streptococcus characterize by the presence of group B Lancefield antigen. These bacteria cause Group B streptococcal infection. Streptococcus agalactiae is a species of the normal flora of the gut and female urogenital tract. Early perinatal infection causes septicemia, pneumonia or meningitis, which are associated with a high mortality. During delivery, a baby can acquire S. agalactiae and develop neonatal sepsis, neonatal meningitis, and/or neonatal pneumonia. Neonates with meningitis do not present with the hallmark sign of adult meningitis, a stiff neck. They display nonspecific symptoms such as fever, vomiting, poor feeding, and irritability. The polysaccharide antiphagocytic capsule is this bacterium's main virulence factor.