Invasive group B streptococcal disease in Maryland nursing home residents.

Between 1991 and 1995, among 999 nonpregnant adult Maryland residents with group B Streptococcus (GBS) isolated from a normally sterile site, 84 resided in nursing homes (NHs). The age-adjusted annual incidence of GBS infection (per 100,000 population) among those > or = 65 years old was 72.3 for NH residents and 17.5 for community residents (relative risk, 4.1; P < 0.001). Thirty-four case patients resided in 11 NHs with > or = 2 cases; 1 NH had 8 case patients within 22 months. Six of 8 case patients from 3 NHs had serotype V GBS. Molecular subtyping of several isolates identified 2 case patients in 1 NH with identical subtype patterns. NH residents have a markedly higher incidence of invasive GBS than do community residents > or = 65 years old and may serve as a target group for immunization when GBS vaccines become available. Further evaluation of intra-NH transmission of GBS is warranted.

Invasive pneumococcal infection in Baltimore, Md: implications for immunization policy.

BACKGROUND: Streptococcus pneumoniae is a leading cause of infectious morbidity and mortality. Although blacks are known to have a higher incidence of invasive pneumococcal infection than whites, detailed analyses of these differences and their implications for vaccine prevention have not been reported. OBJECTIVE: To describe the epidemiological characteristics of invasive pneumococcal infection in Baltimore, Md, and its implications for immunization policy. METHODS: Analysis of active, laboratory-based surveillance during 1995 and 1996 among residents of the Baltimore metropolitan area. RESULTS: Of 1412 cases, 615 patients (43.6%) were classified as white and 766 (54.2%) as black. The annual incidence of invasive pneumococcal infection among white and black residents of the Baltimore metropolitan area was 17.8 and 59.2 per 100000 population, respectively (P<.01). Among patients aged 18 years and older, the median age of blacks with invasive pneumococcal infections was 27 years younger than that of whites (P<.01). Among males 40 to 49 years old, blacks had a 12-fold higher average incidence than whites (average incidence, 114.5 and 9.3, respectively; P<.01). By the age of 65 years, 83.8% of cases had occurred in black adults, as compared with 43.8% in white adults (P<.01). In a regression model, age, black race, male sex, low median family income, and county prevalence of acquired immunodeficiency syndrome were each independently associated with a higher incidence of pneumococcal infection. CONCLUSIONS: Young urban black adults in the Baltimore metropolitan area have a dramatically higher incidence of invasive pneumococcal infection than whites. The vast majority of cases of invasive pneumococcal infection in blacks occur before age 65 years. Current immunization efforts have not addressed the high incidence of pneumococcal infection in this population.

Risk of meningococcal infection in college students.

CONTEXT: The number of meningococcal outbreaks on college campuses have been increasing in the past few years. However, no published studies have documented the incidence of invasive meningococcal infection in college students or whether the incidence is higher than in the general population of the same age. OBJECTIVE: To compare the incidence of invasive meningococcal infection in Maryland college students with that of the general population of the same age. DESIGN: Retrospective cohort study. SETTING AND PATIENTS: Maryland residents with meningococcal infection from 1992-1997 identified from active, laboratory-based, statewide surveillance for invasive meningococcal disease. MAIN OUTCOME MEASURES: Incidence of invasive meningococcal infection. RESULTS: Of 228 patients with invasive meningococcal infection, 67 were aged 16 to 30 years; 11 and 3 of these attended Maryland 4- and 2-year colleges, respectively. Of these, 12 (86%) had infection caused by Neisseria meningitidis serogroups included in the current meningococcal vaccine. The average annual incidence was 1.74 per 100000 among students in 4-year schools vs 1.44 per 100000 for the general population of the same age (P=.60). Among students in 4-year schools, the incidence was 3.24 per 100000 in on-campus residents vs 0.96 per 100000 in off-campus residents (relative risk, 3.4; 95% confidence interval, 1.0-11.6; P=.05). CONCLUSIONS: The incidence of meningococcal infection in college students is similar to the incidence in the general population of the same age, but college students residing on campus appear to be at higher risk than those residing off campus.

Serotype distribution of invasive group B streptococcal isolates in Maryland: implications for vaccine formulation. Maryland Emerging Infections Program.

Invasive group B streptococcal (GBS) infection is a major health problem among infants and adults. The formulation of GBS vaccines depends on knowledge of the GBS serotype distribution. Serotype V GBS infection appears to have recently emerged, suggesting that the serotype distribution changes over time. GBS isolates from 210 pediatric patients, 23 pregnant women, and 314 nonpregnant adults with invasive infection in Maryland were studied. The predominant serotypes from infants with early-onset disease were as follows: serotype III, 38% of isolates; serotype Ia, 36%; serotype V, 13%; and serotype II, 11%. Although the majority (60%) of isolates among infants with late-onset infection were serotype III, serotype Ia (23%) was also common. The predominant serotype among isolates from nonpregnant adult patients was serotype V, accounting for 29% of the isolates. The serotype distribution differs between pediatric patients and adults and is changing over time. The inclusion of a relatively small number of serotypes in a GBS vaccine could provide protection against the vast majority of isolates.

Relapsing invasive group B streptococcal infection in adults.

OBJECTIVE: To study recurrent group B streptococcal infection in adults. DESIGN: Patients with more than one reported group B streptococcal infection were identified through active surveillance for this infection. Sterile-site group B streptococcal isolates were evaluated for serotype and molecular subtyping using restriction endonuclease analysis of chromosomal DNA (REAC). SETTING: All acute-care hospitals in Maryland. PATIENTS: Nonpregnant residents of Maryland 18 years of age or older. RESULTS: 22 adults had at least two group B streptococcal episodes that were separated by 2 to 95 weeks (mean, 24 weeks). Of 395 patients with invasive group B streptococcal infection who survived the first episode and were followed for at least 1 year, 17 (4.3% [95% CI, 2.6% to 6.9%]) had more than one episode. Several patients were found to have endocarditis or osteomyelitis during the second episode. Group B streptococcal isolates from both episodes were obtained from 18 of 22 patients. Of the 18 isolate pairs, 13 (72% [CI, 46% to 90%]) had identical REAC patterns; the probability that at least 13 matches would be found by chance alone was less than 0.000001. Among patients with recurrent infection caused by the same strain, the interval between episodes was shorter (mean, 14 weeks) than that among patients with recurrent infection caused by another strain (mean, 43 weeks; P = 0.05). CONCLUSIONS: Recurrent group B streptococcal infection is common among adults and in most cases appears to be caused by relapse. The optimal management of adults with a first episode of group B streptococcal infection needs to be further defined to minimize the likelihood of recurrent disease.