Cholera in 1997.

The year was marked by a dramatic cholera epidemic affecting the countries in the Horn of Africa. At the end of December almost all countries in this region were affected or threatened by severe cholera outbreaks. Countries affected by major outbreaks were Djibouti, Kenya, Mozambique, Somalia, Uganda and the United Republic of Tanzania. Case-fatality rates (CFR) in some countries were as high as 20%. Most of the cholera outbreaks followed heavy rainfalls which in some countries resulted in huge floods. The El Niño phenomenon is considered to be related to the heavy rainfalls and floods in the Horn of Africa and has destroyed land and displaced populations in several countries, e.g. Djibouti, Ethiopia, Kenya, Somalia, Sudan. All regions of the world have continued to report cholera caused by V. cholerae O1 biotype E1 Tor since 1961 when it first appeared in Indonesia (Map 1). A total of 147,425 cases and 6,274 deaths (CFR 4.3%) were reported in 1997 to WHO (Table 1 and Figs. 1-3). With a total of 118,349 cases, Africa accounted for 80% of the global total. The total number of cases and deaths are similar to the previous year when 143,349 cases and 6,689 deaths were reported with a CFR of 4.7%. Cholera cases were notified from 65 countries in 1997 which is a decrease of 9% compared to 1996 (71 countries). Although the number of countries and the total global number of cases have been decreasing every year since 1992, the CFR is not decreasing and is of major concern. In the Americas, the total number of cases declined by 15.5% from 1996 to 1997. However, by the end of the year, and probably related to the extreme weather changes associated with the El Niño phenomenon, many countries in the region reported unexpected cholera outbreaks.