Disease outbreak investigations--objectives, methods and importance.

In South Africa approximately 100 disease outbreaks or epidemics requiring investigation and control can be anticipated each year. Outbreak investigations play a critical role in determining effective disease control strategies. The application of modern epidemiological methods to the study of disease outbreaks is discussed and problem-solving methodology, which has similarities to the approach used in clinical diagnostics, described. These methods were applied to the investigation of an outbreak of Legionnaire's disease at a Johannesburg teaching hospital.