Definition
By Mayo Clinic staffGroup B streptococcus (strep) is a common bacterium often carried in your intestines or lower genital tract. Group B strep is usually harmless in adults. In newborns, however, it can cause a serious illness known as group B strep disease.
Group B strep can also cause dangerous infections in adults with certain chronic medical conditions, such as diabetes or liver disease. Older adults are at increased risk of illness due to group B strep, too.
If you're a healthy adult, there's nothing you need to do about group B strep. If you're pregnant, get a group B strep screening test during your third trimester. If you have group B strep, antibiotic treatment during labor can protect your baby.
- Puopolo KM, et al. Group B streptococcal infection in neonates and young infants. http://www.uptodate.com/home/index.html. Accessed Sept. 28, 2010.
- Group B strep prevention: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/GroupBStrep/general/gen_public_faq.htm. Accessed Oct. 4, 2010.
- Group B strep prevention: Adult disease. Centers for Disease Control and Prevention. http://www.cdc.gov/groupbstrep/general/gen_public_adult.htm. Accessed Oct. 4, 2010.
- Group B strep prevention: Protect your baby from group B strep! Centers for Disease Control and Prevention. http://www.cdc.gov/groupbstrep/general/protect-your-baby-GBS.htm. Accessed Oct. 4, 2010.
- Ogle JW, et al. Infections: Bacterial & spirochetal. In: Hay WW Jr, et al. Current Diagnosis & Treatment: Pediatrics. 19th ed. New York, N.Y.: McGraw-Hill Medical; 2009. http://www.accessmedicine.com/content.aspx?aid=3410745. Accessed Oct. 4, 2010.
- Lachenauer CS, et al. Group B streptococcus. In: Kliegman RM, et al. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa.: Saunders Elsevier; 2007. http://www.mdconsult.com/das/book/body/221546375-2/0/1608/528.html?tocnode=54478925&fromURL=528.html#4-u1.0-B978-1-4160-2450-7..50185-7_4188. Accessed Oct. 4, 2010.
- Baron M, et al. Group B streptococcal infections in nonpregnant adults. http://www.uptodate.com/home/index.html. Accessed Sept. 28, 2010.
- Apgar BS, et al. Prevention of group B streptococcal disease in the newborn. American Family Physician. 2005;71:903.
- Centers for Disease Control and Prevention, et al. Prevention of perinatal group B streptococcal disease. MMWR. 2002;51:1. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5111a1.htm. Accessed Oct. 7, 2010.


Find Mayo Clinic on