Epidemiology of invasive group B streptococcal disease in the United States, 1999-2005.

CONTEXT: Group B streptococcus is a leading infectious cause of morbidity in newborns and causes substantial disease in elderly individuals. Guidelines for prevention of perinatal disease through intrapartum chemoprophylaxis were revised in 2002. Candidate vaccines are under development. OBJECTIVE: To describe disease trends among populations that might benefit from vaccination and among newborns during a period of evolving prevention strategies. DESIGN AND SETTING: Analysis of active, population-based surveillance in 10 states participating in the Active Bacterial Core surveillance/Emerging Infections Program Network. MAIN OUTCOME MEASURES: Age- and race-specific incidence of invasive group B streptococcal disease. RESULTS: There were 14,573 cases of invasive group B streptococcal disease during 1999-2005, including 1348 deaths. The incidence of invasive group B streptococcal disease among infants from birth through 6 days decreased from 0.47 per 1000 live births in 1999-2001 to 0.34 per 1000 live births in 2003-2005 (P < .001), a relative reduction of 27% (95% confidence interval [CI], 16%-37%). Incidence remained stable among infants aged 7 through 89 days (mean, 0.34 per 1000 live births) and pregnant women (mean, 0.12 per 1000 live births). Among persons aged 15 through 64 years, disease incidence increased from 3.4 per 100,000 population in 1999 to 5.0 per 100,000 in 2005 (chi2(1) for trend, 57; P < .001), a relative increase of 48% (95% CI, 32%-65%). Among adults 65 years or older, incidence increased from 21.5 per 100,000 to 26.0 per 100,000 (chi2(1) for trend, 15; P < .001), a relative increase of 20% (95% CI, 8%-35%). All 4882 isolates tested were susceptible to penicillin, ampicillin, and vancomycin, but 32% and 15% were resistant to erythromycin and clindamycin, respectively. Serotypes Ia, Ib, II, III, and V accounted for 96% of neonatal cases and 88% of adult cases. CONCLUSIONS: Among infants from birth through 6 days, the incidence of group B streptococcal disease was lower in 2003-2005 relative to 1999-2001. This reduction coincided with the release of revised disease prevention guidelines in 2002. However, the disease burden in adults is substantial and increased significantly during the study period.

Risk factors for meningococcal disease in students in grades 9-12.

BACKGROUND: Meningococcal disease is a serious problem in adolescents, including high school students. Universal immunization of adolescents with meningococcal conjugate vaccine was recently recommended. We studied risk factors for meningococcal disease in students in grades 9-12. METHODS: This was a matched case-control study using surveillance for meningococcal disease in students in grades 9-12 in sites throughout the United States. For each case-patient, up to 4 controls were selected from the home room classroom. All subjects answered an extensive questionnaire. Logistic regression was performed to identify risk factors associated with meningococcal disease. Meningococcal isolates were characterized. RESULTS: Of 69 eligible patients, 49 (71%) were enrolled and had at least 1 control. Isolates were available for 59 (86%) cases. Attending at least 1 barbeque or picnic [matched odds ratio (MOR): 0.26, P value = 0.003] or school dance (MOR: 0.30, P = 0.04) were independently associated with decreased risk of meningococcal disease. Male gender (MOR: 2.94, P = 0.009), upper respiratory infection symptoms (MOR: 2.43, P = 0.04), marijuana use (MOR: 4.21, P = 0.009), and nightclub/disco attendance (MOR: 3.30, P = 0.04) were associated with increased risk. Among 54 students not from Oregon (where serogroup B strains predominate) with available serogroup, 38 (73.1%) cases were potentially vaccine preventable: 18 (34.6%) serogroup C, 19 (36.5%) serogroup Y, and 1 (1.9%) serogroup W-135. CONCLUSIONS: Certain behaviors increase the risk of meningococcal infection, whereas others are associated with decreased risk. Most meningococcal disease in high school students can be prevented if recommendations on use of meningococcal conjugate vaccine are implemented.

Multistate shigellosis outbreak and commercially prepared food, United States.

In 2000, shigellosis traced to a commercially prepared dip developed in 406 persons nationwide. An ill employee may have inadvertently contaminated processing equipment. This outbreak demonstrates the vulnerability of the food supply and how infectious organisms can rapidly disseminate through point-source contamination of a widely distributed food item.