Multicenter surveillance of invasive meningococcal infections in children.

Objectives: Meningococcal disease continues to result in substantial morbidity and mortality in children, but there is limited recent surveillance information regarding serogroup distribution and outcome in children in the United States. The objective of this study was to collect demographic, clinical, laboratory, and outcome information for infants and children who had Neisseria meningitidis infections of various serogroups and were cared for in 10 pediatric hospitals.

Methods: Investigators at each of the participating hospitals identified children with meningococcal infections and collected demographic and clinical information using a standard data form. Meningococcal isolates were sent to a central laboratory for serogrouping by slide agglutination and penicillin susceptibility.

Results: From January 1, 2001, through March 15, 2005, 159 episodes of systemic meningococcal infections were detected. The greatest numbers of children were younger than 12 months (n = 41) or were 12 to 24 months of age (n = 22). Meningitis was the most common clinical manifestation of disease accounting for 112 (70%) cases; 43 (27%) children had bacteremia only. Children who were younger than 5 years (17 of 102) were significantly less likely to require mechanical ventilation than children who were 5 to 10 years of age (12 of 24) or children who were older than 10 years (13 of 33). Overall, 55 (44%) isolates were serogroup B, 32 (26%) were serogroup C, and 27 (22%) were serogroup Y. All but 1 isolate (intermediate) were susceptible to penicillin. The overall mortality rate was 8% (13 of 159) but was greater for children who were > or = 11 years of age (7 [21.2%] of 33) than for children who were younger than 11 years (6 [4.8%] of 126). Unilateral or bilateral hearing loss occurred in 14 (12.5%) of 112 children with meningitis.

Conclusions: The morbidity and the mortality of meningococcal infections are substantial. With the recent licensure of meningococcal conjugate vaccines, our baseline trends in meningococcal disease can be compared with those seen after widespread vaccination to assess the success of routine immunization.