Compiled Body of Works in Field Epidemiology

Background: A single case of cholera initiates outbreak investigation in Ethiopia. Nifas Silk Lafto sub-city Public Health Emergency Management reported acute watery diarrhea case on 7 September, 2017. We investigated the outbreak to identify its etiology, source, associated risk factors and to control the outbreak. Methods: We compared cases with health center-based unmatched controls(2:1). We defined suspected cases of cholera as occurrence of acute watery diarrhea, with or without vomiting, in a patient aged ≥5 years living in 02, 03 and 04 woredas of Nefas Silk Lafto sub-city between 7 September and 01 October 2017. Whereas, controls were individuals aged ≥5 years without history of acute watery diarrhea. We searched new cases, assessed houses of cases and holy waters, and collected data using structured questionnaire. We described the outbreak by descriptive epidemiology and then conducted unmatched case-control study. Epi Info™ version 7.2.0.1 was used for bivariate and multivariate analysis. Results: The outbreak began on 07 September, 2017 reaching its peak on 23 September, 2017 and ended on 01 October, 2017. We identified a total of 25 cases(Median age: 38 years; IQR:20) and recruited 50 controls (Median age: 35 years; IQR:29). An overall attack rate was 0.03%. Attack rate was nearly equal in females (0.04%) and males (0.03%). Attack rate was highest in 15-24 years (0.10%) and lowest in 35-44 years (0.02%)