Group B Streptococcus or group B strep species are spherical bacteria that are part of the normal flora of many healthy individuals but can cause life-threatening infections of the bloodstream, urinary tract, skin and lungs due to various causes. In fact, according to the Directors of Health Promotion and Education, about 18,000 individuals get infected with group B strep each year in the United States. The fatality rate is about 20 percent in infected adults and about 5 to 15 percent in infected newborns.
While many individuals carry group B strep in their bodies, most of them do not develop infections from it. Individuals with reduced immunity such as the very young and the very old as well as those with chronic health conditions are prone to group B strep infections. A study published in the September 1995 edition of the "Annals of Internal Medicine" showed that 63 percent of patients with community-acquired group B strep infections had at least one chronic condition such as diabetes, cirrhosis, breast cancer, neurogenic bladder or stroke, while 22 percent of hospital-acquired infections were associated with the placement of a central venous line, diabetes, congestive heart failure and seizure disorder.
The Directors of Health Promotion and Education states that 10 to 30 percent of pregnant women are colonized with group B strep in their genital tracts; each year about 8,000 newborns in the U.S. acquire the infection from their mothers during vaginal delivery. Babies born to women who have already had a baby with group B strep infection, who have a urinary tract infection caused by group B strep, who become colonized with group B strep late in pregnancy, who have a rupture of membranes 18 hours or more before delivery, or who begin labor before 37 weeks are at a greater risk. Intravenous antibiotics are commonly recommended for laboring women with risk factors. In mothers who do not receive antibiotics during labor, the newborn has a high risk of developing group B strep infections characterized by fever, difficulty feeding, irritability or lethargy. Antibiotics are given to such babies, but many newborns who survive may develop speech, hearing and vision problems as well as mental retardation.
Group B strep is a known pathogen of fish and cows. According to a study published in the November 2007 edition of "Annals of Epidemiology," fish consumption increased the risk of acquiring group B strep colonization, but beef and milk from cows infected with group B strep were found to be safe. Colonization, however, does not indicate infection or disease. None of the participants in the study suffered ill effects from group B colonization. The same study postulates that as many as 17 percent of infections in newborns and adults associated with strep B colonization may be attributed to the consumption of fish. The study did not explore the types of fish or how the fish was prepared.