dition, research involving a GBS vaccine promises to provide long term protection (ACOG Tech. Bull. #170, 1993, p. 55). This paper reviews the characteristics of the GBS organism, the epidemiology of GBS infection, and the risk factors associated with its transmission. In addition, treatment approaches and nursing considerations are also elucidated.
The genus, Streptococcus, contains three major groups. Of these, the Staphylococcus pyogenes (or leukocyte stimulating) group are known to be harmful to humans (Fuller, 1992, p. 487). These bacteria are single celled, sphere shaped, gram positive facultative anaerobes. Typically, they clump together to form chains and clusters. One of their main characteristics is in vitro beta hemolysis. Although GBS is usually transmitted by the venereal route, the organism is not normally a pathogen in healthy nonpregnant women. It is in the perinatal population, however, that GBS becomes physiologically significant.
GBS bacteria are typically found in the maternal gastrointestinal tract, vagina, cervix, vulvar, and periurethral areas (Hueston, 1991, p. 487). Somewhere between 15% and 40% of pregnant women are asymptomatic carriers; the most common sites of colonization are the rectum and vagina. Moreover, colonization rates tend to show both great variability. In addition to GBS being more prevalent in the U.S., vaginal cultures taken serially during any given pregnancy may be only intermittently positive (ACOG Tech. Bull. #170, 1993, p. 55). Neonatal GBS disease can be divided into two distinct clinical syndromes: early onset GBS disease and late onset GBS disease. In the early onset syndrome, infection is acquired from the maternal genital tract through either ascending infection in utero just prior to birth or during the neonate's passage through the birth canal. When surface cultures are performed soon after birth, approximately 50% to 70% of exposed infants demon...