Meningococcal disease in siblings caused by rifampicin sensitive and rifampicin resistant strains.

Two brothers presented with meningococcal infection in a five day period, the first with a rifampicin sensitive strain and the second, who had received rifampicin chemoprophylaxis, with a resistant strain. Secondary cases of meningococcal disease can occur despite chemoprophylaxis, and may be rifampicin resistant. Close contacts should be informed of the early symptoms of meningococcal disease and of the need to seek medical advice urgently if they occur.