Cholera Outbreak Investigation in Adamawa State, Nigeria 2021: An Unmatched Case Control Study
- Water or foodborne
- Vaccine preventable diseases
Background
Cholera, a diarrheal disease caused by the bacterium Vibrio cholerae remains a serious public-health problem in Nigeria. In 2018, 43,996 cholera cases and 836 deaths were recorded across 20 states in Nigeria with CFR of 1.9%. The Adamawa State Ministry of Health (SMOH) confirmed an outbreak of cholera in the state affecting 12 out of its 21 Local Government Areas (LGA) on September 9, 2021. The Nigeria Centre for Disease Control (NCDC) deployed an outbreak response team on October 19, 2021, to Adamawa State to identify risk factors contributing to the outbreak and institute control measures.
Methods
We defined a case of cholera as “any person aged ≥5 years with acute watery diarrhea with or without vomiting living in Adamawa State from June 19th, to December 31st, 2021. We conducted an unmatched case-control study with 66 cases and 120 controls. We enrolled new cases from health facilities and neighborhood controls from affected communities. A structured questionnaire was used to obtain information from the cases and controls. We estimated adjusted odds ratios (aORs) and 95% confidence intervals (95% C.I.) for associations between risk factors and cholera.
Results
The median age of cases and controls was 24.0 (range: 1-76) and 32.0 (range: 5-70). Males accounted for 54.5% of cases and 53.3% of controls. Among cases and controls 84.9% and 82.5% were unemployed respectively. Being younger than 10 years (aOR= 9.7; CI=2.6-34.9) and eating noodles from street vendors (aOR= 7.00; CI=1.4-34.8) were found to be independently associated with cholera.
Conclusion
We educated the community and food vendors on proper hygiene, and distributed chlorine tablets. We recommended that the SMOH should continue to educate food vendors and handlers about cholera and the importance of personal, food, and environmental hygiene.
Cholera, a diarrheal disease caused by the bacterium Vibrio cholerae remains a serious public-health problem in Nigeria. In 2018, 43,996 cholera cases and 836 deaths were recorded across 20 states in Nigeria with CFR of 1.9%. The Adamawa State Ministry of Health (SMOH) confirmed an outbreak of cholera in the state affecting 12 out of its 21 Local Government Areas (LGA) on September 9, 2021. The Nigeria Centre for Disease Control (NCDC) deployed an outbreak response team on October 19, 2021, to Adamawa State to identify risk factors contributing to the outbreak and institute control measures.
Methods
We defined a case of cholera as “any person aged ≥5 years with acute watery diarrhea with or without vomiting living in Adamawa State from June 19th, to December 31st, 2021. We conducted an unmatched case-control study with 66 cases and 120 controls. We enrolled new cases from health facilities and neighborhood controls from affected communities. A structured questionnaire was used to obtain information from the cases and controls. We estimated adjusted odds ratios (aORs) and 95% confidence intervals (95% C.I.) for associations between risk factors and cholera.
Results
The median age of cases and controls was 24.0 (range: 1-76) and 32.0 (range: 5-70). Males accounted for 54.5% of cases and 53.3% of controls. Among cases and controls 84.9% and 82.5% were unemployed respectively. Being younger than 10 years (aOR= 9.7; CI=2.6-34.9) and eating noodles from street vendors (aOR= 7.00; CI=1.4-34.8) were found to be independently associated with cholera.
Conclusion
We educated the community and food vendors on proper hygiene, and distributed chlorine tablets. We recommended that the SMOH should continue to educate food vendors and handlers about cholera and the importance of personal, food, and environmental hygiene.