Cholera: a new homeland in Africa?

Abstract

Cholera was largely eliminated from industrialized countries by water and sewage treatment over a century ago. Today it remains a significant cause of morbidity and mortality in developing countries, where it is a marker for inadequate drinking water and sanitation infrastructure. Death from cholera can be prevented through simple treatment-oral, or in severe cases, intravenous rehydration. The cholera case-fatality rate therefore reflects access to basic health care. We reviewed World Health Organization (WHO) data on cholera cases and deaths reported between 1960 and 2005. In the 1960s, at the beginning of the seventh and current cholera pandemic, cholera had an exclusively Asian focus. In 1970, the pandemic reached sub-Saharan Africa, where it has remained entrenched. In 1991, the seventh pandemic reached Latin America, resulting in nearly 1 million reported cases from the region within 3 years. In contrast to the persisting situation in Africa, cholera was largely eliminated from Latin America within a decade. In 2005, 31 (78%) of the 40 countries that reported indigenous cases of cholera to WHO were in sub-Saharan Africa. The reported incidence of indigenous cholera in sub-Saharan Africa in 2005 (166 cases/million population) was 95 times higher than the reported incidence in Asia (1.74 cases/million population) and 16,600 times higher than the reported incidence in Latin America (0.01 cases/million population). In that same year, the cholera case fatality rate in sub-Saharan Africa (1.8%) was 3 times higher than that in Asia (0.6%); no cholera deaths were reported in Latin America. The persistence or control of cholera in Africa will be a key indicator of global efforts to reach the Millennium Development Goals and of recent commitments by leaders of the G-8 countries to increase development aid to the region.