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.