Streptococcus agalactiae

bacterium

Also known as: group B streptococcus

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Last updated

July 17, 2026

Quick Summary

Streptococcus agalactiae, also known as group B streptococcus (GBS), is a type of bacterium that typically grows in chains. These bacteria are gram-positive and nonmotile.12

While some streptococci are beneficial and used in food production, S. agalactiae can cause infections in humans. In pregnant women, it can lead to bladder and uterine infections. For newborn infants, GBS infection can result in serious conditions such as sepsis (blood poisoning), meningitis (inflammation of the membranes around the brain and spinal cord), or pneumonia.21

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” Streptococcus agalactiae, or group B streptococcus bacteria, can cause infections of the bladder and uterus in pregnant women; in newborn infants infection with the bacterium may result in sepsis (blood poisoning), meningitis (inflammation of the membranes covering the brain and spinal cord), or pneumonia.
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” Streptococcus agalactiae, or group B streptococcus bacteria, can cause infections of the bladder and uterus in pregnant women; in newborn infants infection with the bacterium may result in sepsis (blood poisoning), meningitis (inflammation of the membranes covering the brain and spinal cord), or pneumonia.
Read More