One health surveillance: linking human and animal rabies surveillance data in Kenya

Samuel Kahariri^1,2,3,4*Lian F Thomas^2,5Bernard Bett²Marianne W Mureithi⁴Brian Njuguna³Mutono Nyamai^3,6,7SM Thumbi^3,6,7,8

• ¹state department for livestock - Directorate of Policy, Research and Regulations, Nairobi, Kenya
• ²International Livestock Research Institute (ILRI), Nairobi, Kenya
• ³Center for Epidemiological Modelling and Analysis, Institute of Tropical and Infectious Diseases, University of Nairobi, Nairobi, Kenya
• ⁴Department of Medical Microbiology & Immunology, Faculty of Health Sciences, University of Nairobi, Nairobi, Kenya
• ⁵Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
• ⁶Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States
• ⁷Feed the Future Innovation Lab for Animal Health, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States
• ⁸Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburg, Scotland, United Kingdom

Rabies poses a significant public health and economic challenge in Kenya. The Kenya rabies elimination strategy identifies surveillance as a key pillar to achieve the targets of ending human deaths from rabies by 2030. Here we investigated the utility of the national human and animal rabies surveillance data to provide robust surveillance data to guide the Kenya rabies elimination program.We conducted a retrospective analysis of the official rabies data obtained from the national human and animal health surveillance systems between 2017 to 2023. We obtained data on bites, cases, and deaths in dogs and humans due to rabies. We estimated incidences and tested the relationships between rabies variables in human and dogs as a proxy for robust data availability.On average, there were 162 cases and 84 deaths in dogs, while in humans, there were 53 cases and 6 deaths. We found positive correlations between dog bites and cases of dog rabies (RR = 1.33, 95% credible interval [CI]: 1.16, 1.54), deaths and rabies cases in dogs (RR = 1.09, 95% CI: 1.05, 1.14) and death cases and dog bites (RR = 1.46, 95% CI: 1.06, 1.98). However, relationships between rabies cases and dog bites in humans were not statistically significant (RR = 1.00, 95% CI: 0.98, 1.03), whereas rabies cases in dogs and humans were negatively correlated (RR = 0.82, 95% CI: 0.68, 0.94).The findings indicate that Kenya's rabies surveillance system effectively captures trends in dog rabies but has gaps in human rabies case reporting. The weak relationship between rabies cases and dog bites in humans and the negative correlation between rabies cases in dogs and humans point to potential underreporting of human cases, that could be possibly driven by misdiagnosis or limited access to healthcare, or effective post-exposure treatment.Understanding these relationships is critical for improving the surveillance systems that can effectively support the rabies elimination program.