Healthy Living

What Is Group B Strep Infection?

What Is Group B Strep Infection?

Key Takeaways

  • Causes of group B strep infection
  • Treatment for GBS infection
  • Diagnosis

What is Group B Strep Infection?

Group B strep  (GBS) is a serious infection mainly caused by group B streptococcus bacteria, which inhabits the human intestines. Group B strep bacteria does not only affect adults. It can be seen in infants, leading to a serious illness known as strep B infection. In adults, group B strep bacteria can lead to other dangerous infections, such as liver disease and diabetes. Older people are at high risk of developing diabetes and liver infections if they are infected with group B strep bacteria.

If you are an adult, there isn't as much that can be done. However, if you are pregnant, make sure you test for group B strep before your third trimester. This is mainly for the sake of your unborn baby. In case you have group B strep during pregnancy, a treatment of antibiotics before or during labor can help protect your baby.

What is the cause of Group B strep infection?

Group B strep infection is found in 25% of adults, usually pregnant women. The bacteria causing this infection is commonly found in the vagina, intestines, and the rectal area. Most mothers who are carriers of group B strep bacteria will not show any symptoms unless other circumstances are responsible. This is where the infection has infected both the mother and the child. When the disease affects the child at the age of 1-3 weeks, it is referred to as an late-onset disease. According to research, about 1,000 babies in the USA develop early-onset group B strep disease every year. The same figure is believed to have late-onset group B infection every year.

How is group B strep infection transmitted?

For protection purposes, it is important to know how group B strep infection is transmitted. In newly born babies, GBS disease is transmitted through direct contact with GBS bacteria, while still in the uterus or in the process of delivery. About 50% of the infected mothers are likely to pass the GBS bacteria to their unborn babies during pregnancy and also through vaginal delivery. Not all babies will be affected by the bacteria if their mothers have the infection. However, statistics show that only one out of 100 to 200 babies born by a GBS infected mother will get the GBS infection. GBS infection is less common in Caucasian Americans compared to African Americans. This may be a result of maternal factors that increase the chances of transmitting the bacteria from the mother to the child leading to early-onset of GBS infection.

These factors include:

  • Fever at time of labor
  • A history of previous children with the infection
  • Membrane and labor rupture before 37 weeks of gestation
  • Membrane rupture for 18 or more hours before delivery
  • Infection of the urinary tract with Group B strep bacteria during pregnancy
  • Positive identification of GBS culture at 35 to 37 weeks of pregnancy

The late-onset of group B disease mainly occur in babies who are prematurely born and in the babies whom their mothers tested positive for group B bacteria during the pregnancy.

Signs and Symptoms of Group B Strep Infection

For the newly born babies who have early-onset group B disease, the signs and symptoms of the infection appear within the first 24 hours after birth. For the babies who develop late-onset GBS disease, they live a healthy life even with the signs and symptoms appearing after and before the first week. The signs and symptoms, as seen in infants infected with GBS, include:

  • Brain seizures
  • Breathing difficulties accompanied by grunting sounds
  • Fever
  • Cyanosis (blue coloration of the skin)
  • Fussiness
  • Vomiting
  • Reduced appetite and poor feeding
  • Diarrhea
  • Increase pulse rate and abnormal blood pressure
  • Stiffness

Older people who are colonized by GBS bacteria may develop the following signs and symptoms:

  • Infection of bones and joints
  • Infection of the blood circulatory system known as sepsis
  • Infection of the urinary tract
  • Infection of the skin and body soft tissues
  • Pneumonia infection
  • Rare infection of the interstitial fluid and cerebrospinal fluids

The source of GBS infection in non-pregnant adults is still not identified.

Diagnosis for Group B Strep Infection

Group B strep infection should be screened between the 35th and 37th weeks of pregnancy. Your healthcare professional will take a sample from the mother’s rectum or vagina and then send it to the laboratory for testing. A positive test for GBS infection indicates that you have the GBS bacteria in your system. This doesn’t mean that you are going to experience the signs and symptoms or that your baby will be affected. This means that your unborn baby has the potential to get the infection, and you should do something to protect him or her.

In case you have already delivered and your doctor suspects that your child has group B strep infection, a sample of your baby’s blood is will be taken to the laboratory for examination. During diagnosis for group B strep infection or disease, the blood samples are cultured and then screened under a powerful microscope. The cultures take a lot of time to grow; hence it may take 2-3 days to get your results from the lab analysis.

Chest X-ray scan is also recommended to test for pneumonia if the symptoms of the infection are contradicting.

Treatment for Group B Strep Infection

Pregnant women who test positive for group B step infection at the time of pregnancy, plus those with risk factors for developing the infection, should be administered antibiotics. Administration of some antibiotics in women before giving birth cannot be an effective way of preventing early-onset GBS. This is because the GBS bacteria grow back very quickly. Pregnant women who have GBS and are isolated from their urine at any time of their pregnancy or those who have children with a history of GBS infection should be treated with antibiotics at time of labor. Pregnant women who do not know their GBS status should also be given antibiotics at the time of labor in case they develop preterm labor. Penicillin or its brand ampicillin are the recommended antibiotic. Patients who are allergic to penicillin can have a dose of clindamycin and cefazolin. Use of antibiotics has been seen to decrease the effects and symptoms of GBS of early-onset GBS. However, antibiotics are not able to take control of the late-onset group B strep infection. If a pregnant GBS carrier receives an intravenous injection of antibiotics at delivery time, her child has lower chances of getting GBS disease. Without antibiotics, the child has high possibility of getting group B strep infection.

For non-pregnant and neonates who happen to contract an invasive group B strep infection, administration of antibiotics can make a difference. Some conditions of invasive GBS infection may require surgical operation. For example, a surgical debridement is done to some people with skin, bone, and soft tissue infections as a result of GBS infection.

Bottom Line

Group B strep infection is a condition that affects children much more than adults. The effects of symptoms of GBS infection can be threatening, although it is very treatable. GBS is an infection which can be prevented, as well. Administration of antibiotics can act as both the control and the cure for group B strep infection.