Hepatitis E in Karamoja, Uganda, 2009-2012: epidemiology and challenges to control in a setting of semi-nomadic pastoralism.

BACKGROUND: A prolonged hepatitis E outbreak occurred between 2009 and 2012 among a semi-nomadic pastoralist population in the Karamoja region of Uganda. As data on the public health problems of nomadic pastoralists in sub-Saharan Africa is limited, we sought to characterize the epidemiology and challenges to control of hepatitis E in such a setting. METHODS: A retrospective case-series investigation was undertaken. Surveillance line-lists of suspected hepatitis E cases maintained during the outbreak were analyzed. Standardized interviews and focus group discussions were conducted with key informants involved in outbreak control activities. RESULTS: Between August 2009 and September 2012, 987 hepatitis E cases with individual case-based data were identified. Of 22 total deaths, almost half occurred during the first 4 months of the outbreak. Infection attack rates were higher among males and young adults. The average time between onset of jaundice and presentation was approximately 1 week. Challenges to control were related to persistent consumption of untreated water, poor sanitation infrastructure, remote geography, nomadic movement and civil insecurity. CONCLUSIONS: The hepatitis E outbreak in Karamoja highlights the emergence of sanitation and hygiene-related disease among semi-nomadic pastoralist populations. Improving sanitation and safe water access and extending health education programs to remote pastoralist communities is crucial to prevent such diseases from becoming endemic.