Cholera outbreak in Addis Ababa, Ethiopia: A case-control study

Area of Science:

• Public Health
• Epidemiology
• Infectious Diseases

Background:

• Cholera outbreaks are a recurring public health issue in Addis Ababa, particularly during rainy seasons.
• Limited data on risk factors hinders effective cholera outbreak interventions in the region.
• This study investigated a recent cholera outbreak to determine its etiology, source, and risk factors for control.

Purpose of the Study:

• To identify the causative agent, source, and transmission routes of a cholera outbreak in Addis Ababa.
• To determine key risk factors associated with the cholera outbreak.
• To provide evidence-based recommendations for cholera outbreak control and prevention.

Main Methods:

• A case-control study was conducted, comparing 25 cholera cases with 50 health center-based controls (1:2 ratio).
• Data on demographics and potential risk factors were collected using a structured questionnaire.
• Unconditional logistic regression was employed to analyze risk factors and identify protective measures.

Main Results:

• The outbreak occurred from September 7 to October 1, 2017, with 25 confirmed cases of acute watery diarrhea and dehydration.
• Vibrio cholerae O1 Ogawa was identified in stool and water samples.
• Consumption of contaminated holy water (AOR: 20.5) and raw vegetables (AOR: 15.3) were significant risk factors; handwashing with soap was protective (AOR: 0.04).

Conclusions:

• Cholera transmission was attributed to both foodborne (raw vegetables) and waterborne (contaminated holy water) routes.
• Effective cholera control requires addressing both contaminated food and water sources.
• Promoting handwashing with soap and proper food preparation (cooking vegetables) are crucial preventive strategies.