Progress in Quest for Group B Strep Vaccine
Study Shows Vaccine Is Effective in Women of Childbearing Age
Oct. 30, 2009 (Philadelphia) -- Researchers are a step closer to developing
a vaccine to protect pregnant women against a serious bacterial infection that
is a leading cause of death and disability in newborns.
The bug is called group B streptococcus, more commonly referred to as group
B strep. Pregnant women with group B strep infection or who are colonized with
the bacteria -- meaning they carry the bug but aren't sick from it -- can
transmit the bacteria to the fetus during delivery. It's commonly found in the
vagina and rectum, with about 25% of women carrying it at any time; most will
carry the bacteria and have no symptoms.
Group B strep can cause life-threatening infections in newborns in the hours
after birth, during the first week of life, or even several months later, says
Neil Fishman, MD, an infectious diseases specialist at the University of
Currently, women are screened a few weeks prior to delivery; if the test is
positive, they are given antibiotics to wipe out the infection. "But this isn't
perfect as the bacteria can be resistant to the antibiotics," Fishman tells
Developing a vaccine against group B strep is a major goal, he says.
The new study involved 650 women of childbearing age who were not carriers
of group B strep. About half were given the new vaccine. The women were checked
for group B strep bacteria twice a month for 18 months.
The vaccine caused a modest but lasting reduction in group B strep
colonization in the vagina and rectum, says researcher Sharon Hillier, PhD, of
the Magee-Womens Research Institute at the University of Pittsburgh.
Colonization of the genital or gastrointestinal tract is the major risk factor
The vaccine also elicited a strong immune response against the bacteria, she
tells WebMD. And the vaccine was safe.
Emory University's Larry Pickering, MD, a senior advisor to the CDC's
National Immunization Program, says that while preliminary, the work is very
"It's important in that they showed it prevented colonization" in both the
GI tract and vagina, he tells WebMD. "But there's still a lot of work to