Group B strep disease
Group B strep disease
Group 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.
In infants, illness caused by group B strep can take two forms: early-onset or late-onset.
Early-onset group B strep disease. This is the more common and serious form of group B strep disease in infants. A baby with early-onset group B strep disease typically becomes sick within 12 hours after birth. Signs and symptoms may include:
Late-onset group B strep disease. Late-onset group B strep disease develops within a week to a few months after birth. Signs and symptoms may include:
In some cases, group B strep may cause a urinary tract infection or other more serious infections such as blood infections (bacteremia) or pneumonia.
When to see a doctor
If you notice your infant has any of the signs or symptoms of group B strep disease, tell your baby's doctor immediately.
Many healthy people carry group B strep bacteria in their bodies. Group B strep bacteria aren't sexually transmitted, and they're not spread through food or water. You may carry group B strep in your body for just a short period of time, it may come and go, or you may always have it.
Group B strep can spread to a baby during a vaginal delivery if the baby is exposed to — or swallows — fluids containing group B strep.
Some individuals, such as older adults and those with chronic health conditions, can develop a more serious infection from group B strep. However, the reason this occurs in some people but not others isn't known.
Group B strep infection can lead to life-threatening complications in infants, including:
If you're a pregnant woman, group B strep can cause:
If you're an older adult or you have a chronic health condition, group B strep bacteria may cause complications such as:
Tests and diagnosis
If you're pregnant, the Centers for Disease Control and Prevention recommends a group B strep screening between weeks 35 and 37 of pregnancy. Your doctor will take a swab sample from your vagina and rectum and send it to a lab for testing. A positive test indicates that you carry group B strep. It doesn't mean that you're ill or that your baby will be affected. It simply means the potential for newborn infection exists, and you can take steps to protect your baby.
If you've already given birth and your doctor suspects your baby has group B strep disease, a sample of your baby's blood or spinal fluid will be sent to a lab for evaluation.
Group B strep infection and group B strep disease are diagnosed when the bacteria are grown from cultures of the fluid samples. The cultures take several days to grow, so it may be two to three days before you receive the results of the lab analysis.
Treatments and drugs
To prevent group B bacteria from spreading to your baby during labor, your doctor can give you an IV antibiotic — usually penicillin or a related drug — when labor begins. If you're allergic to penicillin and related drugs, you may receive clindamycin or a similar alternative. Taking oral antibiotics ahead of time won't help because the bacterium can return before labor begins.
Antibiotic treatment during labor is also recommended if you:
Antibiotic therapy isn't usually needed if you have a C-section delivery, unless your water breaks or labor has already begun before surgery.
If you test positive for group B strep, remind your health care team during labor. Your reminders will help your health care team provide the best possible care during labor and delivery.
Group B strep typically doesn't affect the length of time you and your baby spend in the hospital, and it doesn't affect your ability to breast-feed safely.
Vaccine in development
Last Updated: 2010-12-04
© 1998-2014 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "Mayo Clinic Health Information," "Reliable information for a healthier life" and the triple-shield Mayo logo are trademarks of Mayo Foundation for Medical Education and Research.
Terms and conditions of use