Session: Poster Session: Pediatric Vaccines
Saturday, October 25, 2008: 12:00 AM
Room: Hall C
Background: Infants <12 months have the highest rates of meningococcal disease (MD). Quadrivalent conjugate vaccines (serogroups A,C,Y, and W-135) are not licensed in the United States for children <2 years and there are no serogroup B vaccines. Understanding age-specific epidemiology of MD in infants has important implications for future prevention strategies. Methods: Active laboratory-based surveillance for MD was conducted from 1996-2005 through the Active Bacterial Core surveillance program (surveillance population infants <1 year ~400,000). A confirmed case was defined as isolation of N. meningitidis from a normally sterile body site from an infant with clinically compatible illness. Incidence rates were calculated using U.S census data and estimates of the number of cases in the 50 US states were calculated standardizing for race and age group. Results: From 1996 to 2005, there were an annual estimated 255 cases of MD in infants <12 months (rate=6.75/100,000) with a case-fatality rate of 5.9%. Fifty-five percent of cases were caused by N. meningitidis serogroup B, 27% Y, 10% C, 4% W-135, and 4% non-groupables. Disease peaked in incidence among 2-3 month-olds (8.2/100,000) and was lowest among 8-9 month-olds (2.8/100,000). Combined serogroup C and Y incidence was highest among 4-5 month-olds (3.2/100,000). An estimated 63 cases of serogroup C and Y disease occurred annually in 0-5 month-olds compared to 37 cases among 6-11 month-olds. Conclusion: A high proportion of MD in infants is caused by serogroup B. However, there is a substantial burden of disease caused by serogroups C and Y, especially in infants <6 months. Serogroup B vaccines and conjugate vaccines that protect early in the first year of life are needed to prevent MD in infants.
Previous Abstract | Next Abstract >>