It makes it possible to follow the control of an epidemic. This system needs to be continued, and further strengthened. Almost all major epidemics in terms of numbers of cases in this period occurred in the meningitis belt. It is expected that Ethiopia will soon have an outbreak of meningococcal disease, given the outbreak of Sudan in 1999. The number of cases in the years immediately proceeding and following large epidemics are often elevated and sometimes reach epidemic levels.
Some reports arrive late, when there are already a considerable number of cases.
The reported case fatality rate is higher in the beginning of an epidemic than at the end. Apart from a genuine change caused by better treatment, a major reason for this is a change in reporting practices. The number and intensity of epidemics of meningococcal disease in the meningitis belt has been increasing since the late 1970s with many large epidemics affecting tens of thousands of people. The epidemiology of meningococcal disease is complex, and although we have some knowledge about risk factors for epidemics, much more needs to be learned about disease transmission in order to develop effective strategies for prevention. Response to epidemic meningitis in Africa, 1997.