Protracted cholera outbreak in the Central Region, Ghana, 2016

Objective: On 24th October 2016, the Central Regional Health Directorate received report of a suspected cholera outbreak in the Cape Coast Metropolis (CCM). We investigated to confirm the diagnosis, identify risk factors and implement control measures. Design: We used a descriptive study followed by 1:2 unmatched case-control study. Data source: We reviewed medical records, conducted active case search and contact tracing, interviewed case-patients and their contacts and conducted environmental assessment. Case-patients' stool samples were tested with point of care test kits (SD Bioline Cholera Ag 01/0139) and sent to the Cape Coast Teaching Hospital Laboratory for confirmation. Main outcomes: Cause of outbreak, risk factors associated with spread of outbreak Results: Vibrio cholerae serotype Ogawa caused the outbreak. There was no mortality. Of 704 case-patients, 371(52.7%) were males and 55(7.8%) were aged under-five years. The median age was 23 years (interquartile range: 16-32 years). About a third 248(35.2%) of the case patients were aged 15-24 years. The University of Cape Coast subdistrict was the epicenter with 341(48.44%) cases. Compared to controls, cholera case-patients were more likely to have visited Cholera Treatment Centers (CTC) (aOR=12.1, 95%CI: 1.5-101.3), drank pipe-borne water (aOR=11.7, 95%CI: 3.3-41.8), or drank street-vended sachet water (aOR=11.0, 95%CI: 3.7-32.9). Open defecation and broken sewage pipes were observed in the epicenter. Conclusion: Vibrio cholerae serotype Ogawa caused the CCM cholera outbreak mostly affecting the youth. Visiting CTC was a major risk factor. Prompt case-management, contact tracing, health education, restricting access to CTC and implementing water sanitation and hygiene activities helped in the control.