Topic Overview
What is group B streptococcal infection?
Group B
streptococcal (group B strep) infection is a serious bacterial infection that
is a leading cause of death and disability in newborns.
In the
1970s, about half of newborns with group B strep infection died. Today, due to
early recognition and aggressive treatment of the infection, far fewer cases
end in death.
What causes group B streptococcal infection?
Group
B strep bacteria normally exist in the intestine, vagina, or rectum. A pregnant
woman can transmit the bacteria to her fetus during delivery. Some women are
carriers of group B streptococcal bacteria, which means that they carry the
bacteria but have no illness from it. It is unclear why some babies get group B
strep infection and others do not.
Newborns may develop the
infection hours after birth or during the first week of life, or it may happen
several months later. Newborns who develop group B strep within the first week
are most always infected by their mothers. It's not clear how babies who
develop the infection later are exposed to the bacteria.
What are the symptoms?
Newborns infected with
group B strep within the first 6 days of life may get a blood infection (sepsis) or lung infection (pneumonia). Symptoms of late-stage group B strep (7
days to 3 months of age) may include high or low body temperature,
irritability, low energy, raised respiratory rate, and trouble feeding. An
infection of the fluid or tissues that surround the brain and spinal cord
(meningitis) could occur in the early or late stage.
Newborns thought to be infected with group B strep need medical care right
away, as the infection can be deadly.
How is group B streptococcal infection diagnosed?
Guidelines suggest that all pregnant women have prenatal testing (rectal
and vaginal
cultures) for group B strep between 35 to 37 weeks of
pregnancy.1 Babies suspected of being infected are
diagnosed at birth by testing their blood or spinal fluid or both for group B
strep bacteria.
How is it treated?
Pregnant women with group B
strep infection or who are carriers of
group B strep will be given
antibiotics prior to delivery to prevent transmission
of the bacteria to the newborn during delivery. Women who are pregnant and who
have previously given birth to a child with group B strep infection, or who
have had tests that show they carry the bacteria, should be treated with
antibiotics.
Newborns with the infection will also be given
antibiotics. In addition to antibiotics, supportive care including fluids and
ventilation will be given if needed. In some cases, a doctor will treat a
newborn that is suspected of having group B strep infection before test results
have shown infection. This is because not treating strep B infection in
newborns can result in illness or death.
Having a baby by
cesarean section does not prevent the transmission of
group B strep bacteria.