Meningococcal infections in Bolton, 1971-74.

Between December 1970, and the end of June, 1974, there were 82 cases of meningococcal infection, including 14 deaths, in the metropolitan borough of Bolton. This outbreak, caused by a sulphonamide-sensitive group-B strain, was characterised by a high attack-rate in young children, reaching a peak of 184 per 100,000 per year in the 6-11-month age-group. All the deaths were in children under 3 years of age. Nasopharyngeal carriage of the epidemic strain was found in 34% of close family contacts investigated before receiving sulphonamide prophylaxis.