A recent history of disease outbreaks in Kenya, 2007-2022: Findings from routine surveillance data.

Background: Africa reports the highest number of outbreaks globally, accounting for 39% of all outbreaks in 2022. The Integrated Disease Surveillance and Response strategy in Kenya ensures the reporting of outbreaks up to the national level. We present a summary of the burden of reported disease outbreaks in Kenya, 2007-2022.

Methods: We reviewed historical surveillance data, 2007-2022, summarized the annual caseload and deaths of reported outbreaks, and classified the outbreaks into 3 categories, that is high, moderate, and low burden. A nested Poisson regression model was fit to determine whether there was a significant increase in the number of diseases and counties reporting outbreaks over time.

Results: Twenty-three diseases were reported. COVID-19, cholera, epidemic malaria, kala-azar, and measles were associated with a high disease burden. The highest number of diseases reported in a single year was 10. We observed an increase in the number of outbreaks over time (IRR = 1.26, 95% CI [1.22-1.29], p < 0.001), and an increase in the number of counties reporting outbreaks over time (r = 0.97, p < 0.001).

Conclusion: There was an increase in the frequency and geographic occurrence of outbreaks. The differences in outbreak occurrence between counties necessitate targeted and enhanced preventive, preparedness, and response interventions at the sub-national level to reduce the burden of outbreaks.