[Meningococcal epidemic in a boarding school: a rifampicin-resistant secondary case while under chemoprophylaxis].

An epidemic of meningococcal disease after an influenza outbreak in a community of 49 boys (14-18 years) and 8 adults in a boarding-school is reported. The first patient died with all symptoms of the Waterhouse-Friderichsen syndrome. Several hours later, two other boys developed severe septicemia with meningitis and meningitis respectively. N. meningitidis group B susceptible to penicillin and rifampin was isolated. Within the next 8 hours, chemoprophylaxis with rifampin (600 mg twice daily) was started and maintained for 4 days for the whole community. Throat cultures had not been obtained before prophylaxis. Ten other symptomatic boys were admitted to the hospital and treated by penicillin infusion. The results of blood and cerebrospinal fluid cultures were negative, and treatment was therefore discontinued. Five days after the death of the first boy, another boy died with full-blown Waterhouse-Friderichsen syndrome while on chemoprophylaxis. The neisseriae isolated from this patient were rifampin-resistant. Serological investigations in all patients admitted to hospital revealed the existence of concomitant epidemic infection with influenza A and B in this school. We assume that the viral infection made way for the outbreak of the meningococcal disease and for the high rate of secondary meningococcal infection. Chemoprophylaxis with rifampin should not be continued for longer than 2 to 3 days, otherwise the risk of occurrence of rifampin resistant strains of N. meningitidis increases. Hitherto such strains have rarely been isolated in clinically manifest disease.