The dramatic occurrence of meningococcal disease challenges doctors and attracts intense public interest. It is treatable and preventable, so every death raises the question: Could this have been avoided? Last winter’s experience of clusters in schools was the latest round in a struggle to apply rational and effective policies to control disease and panic. A strategist planning to prevent the occurrence and damage of meningococcal disease has various forces to deploy: epidemiology, the recognition of people who are susceptible to infection, vaccines, antibiotics for prophylaxis and treatment, public awareness, and education of doctors and parents.The epidemiology of meningococcal infection is fundamental to any preventive strategy. The incidence in the UK is 2.5–3 cases/100 000/year, 1200 to 2000 cases, with exact numbers depending on case definitions and the year in question.1 2 The age specific annual incidence peaks at 6 months of age (50–60/100 000), falls to 2/100 000 at age 10 years, rises slightly to 5/100 000 in teenagers, and then falls to 1/100 000 in adults.3

Meningococcal disease illustrates the two purposes of notification: to start public health action and to have statistics on incidence. The consultant in communicable disease control must be notified, to ensure that prophylaxis and advice is given to close contacts and that local general practitioners, schools, and nurseries are informed. A prevention strategy depends on a reliable count of cases. Notifications are an enduring source of statistics, but there has been under-reporting in the past. In the last three years there have been fewer laboratory isolates than notifications, which produced problems in the autumn of 1995 when the public were aware of clusters and an increase in notifications, which was not substantiated by laboratory reports.4 The only reliable way to enhance surveillance is to combine sources of data. The laboratory reporting system is accurate for diagnosis, …