Epidemic cholera in Burundi: patterns of transmission in the Great Rift Valley Lake region

After a 14-year hiatus, epidemic cholera swept through Burundi between January and May, 1992. The pattern of transmission was similar to that in 1978, when the seventh pandemic first reached this region. Communities affected were limited to those near Lake Tanganyika and the Rusizi River. The river connects Lake Tanganyika with Lake Kivu to the north in Zaire and Rwanda. To identify sources of infection and risk factors for illness, an epidemiological study was carried out in Rumonge, a lake-shore town where 318 people were admited to hospital with cholera between April 9 and May 31, 1992. The investigation included a case-control study of 56 case-patients and 112 matched controls. Attack rates according to street increased with the street's proximity to Lake Tanganyika (χ 2 test for linear trend, p