High case fatality cholera outbreak in Western Kenya, August 2010

INTRODUCTION Cholera is a disease caused by the bacterium Vibrio cholera and has been an important public health problem since its first pandemic in 1817. Kenya has had numerous outbreaks of cholera ever since it was first detected there during 1971. In August 2010 an outbreak of cholera occurred in Kuria West District spreading to the neighboring Migori District. We conducted an investigation in order to determine the magnitude of the problem and institute control measures. METHODS In order to update the line lists we reviewed records in Migori and Kuria district hospitals and conducted active case search in the community between 30th August and 6th September 2010. Data was analyzed using Epi-Info 3.5.2. RESULTS A total of 114 cases and with 10 deaths (Case Fatality Rate = 9%) were documented. The index case was an 80 years old woman from Mabera Division who had hosted a cultural marriage ceremony a day before the outbreak. The mean age of case patients was 34.5 years (Standard Deviation=23.4) with a range 5 to 80 years. Females accounted for 61.4% of cases; people aged 10-39 years accounted 46.9%, those 40-69 years accounted for 29.2% and those above 70 years accounted for 9.7% of the cases. Sixty percent of deaths occurred among patients aged 50 years and over, case fatality rate was highest in this age group (16.7%) followed by those aged 40-49 years (12.5%), 20-29 years (10%) and 10-19 years (4.8%). The outbreak was confirmed within 2 weeks of onset after one (16.7%) of the six samples taken tested positive for V. cholera (serotype Inaba). CONCLUSION High case fatality rate and late laboratory confirmation was noted in this outbreak. There was urgent need to capacity build the districts on cholera case management, outbreak management, and equip the Migori District Hospital laboratory to allow prompt confirmation.