Multiple pathogens co-exposure and associated risk factors among cattle reared in a wildlife-livestock interface area in Kenya

Sophina Manyenya; Daniel Nthiwa; Harrison Osundwa Lutta; Mathew Muturi; Richard Nyamota; Athman Mwatondo; Grace Watene; James Akoko; Bernard Bett

doi:10.3389/fvets.2024.1415423

Multiple pathogens co-exposure and associated risk factors among cattle reared in a wildlife-livestock interface area in Kenya

Front Vet Sci. 2024 Jul 25:11:1415423. doi: 10.3389/fvets.2024.1415423. eCollection 2024.

Authors

Affiliations

¹ Department of Biological Sciences, University of Embu, Embu, Kenya.
² International Livestock Research Institute, Nairobi, Kenya.
³ Biotechnology Research Institute, Kabete Centre, Kenya Agricultural and Livestock Research Organization, Nairobi, Kenya.
⁴ Kenya Zoonotic Disease Unit, Ministry of Health and Ministry of Agriculture, Livestock, and Fisheries, Nairobi, Kenya.

^# Contributed equally.

Abstract

Introduction: Understanding multi-pathogen infections/exposures in livestock is critical to inform prevention and control measures against infectious diseases. We investigated the co-exposure of foot-and-mouth disease virus (FMDV), Brucella spp., Leptospira spp., and Coxiella burnetii in cattle in three zones stratified by land use change and with different wildlife-livestock interactions in Narok county, Kenya. We also assessed potential risk factors associated with the transmission of these pathogens in cattle.

Methods: We identified five villages purposively, two each for areas with intensive (zone 1) and moderate wildlife-livestock interactions (zone 2) and one for locations with low wildlife-livestock interactions (zone 3). We sampled 1,170 cattle from 390 herds through a cross-sectional study and tested the serum samples for antibodies against the focal pathogens using enzyme-linked immunosorbent assay (ELISA) kits. A questionnaire was administered to gather epidemiological data on the putative risk factors associated with cattle's exposure to the investigated pathogens. Data were analyzed using the Bayesian hierarchical models with herd number as a random effect to adjust for the within-herd clustering of the various co-exposures among cattle.

Results: Overall, 88.0% (95% CI: 85.0-90.5) of the cattle tested positive for at least one of the targeted pathogens, while 41.7% (95% CI: 37.7-45.8) were seropositive to at least two pathogens. FMDV and Brucella spp. had the highest co-exposure at 33.7% (95% CI: 30.9-36.5), followed by FMDV and Leptospira spp. (21.8%, 95% CI: 19.5-24.4), Leptospira spp. and Brucella spp. (8.8%, 95% CI: 7.2-10.6), FMDV and C. burnetii (1.5%, 95% CI: 0.7-2.8), Brucella spp. and C. burnetii (1.0%, 95% CI: 0.3-2.2), and lowest for Leptospira spp. and C. burnetii (0.3%, 95% CI: 0.0-1.2). Cattle with FMDV and Brucella spp., and Brucella spp. and Leptospira spp. co-exposures and those simultaneously exposed to FMDV, Brucella spp. and Leptospira spp. were significantly higher in zone 1 than in zones 2 and 3. However, FMDV and Leptospira spp. co-exposure was higher in zones 1 and 2 than zone 3.

Discussion/conclusion: We recommend the establishment of a One Health surveillance system in the study area to reduce the morbidity of the targeted zoonotic pathogens in cattle and the risks of transmission to humans.

Keywords: Brucella spp.; Coxiella burnetii; Kenya; Leptospira spp.; cattle; co-exposure; foot-and-mouth disease virus; livestock-wildlife interface.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This study was funded by the European Union’s Horizon 2020 Research and Innovation Programme (grant no. 641918) through the African Bioservices project (Linking biodiversity, ecosystem functions, and services in the Serengeti-Mara region, East Africa. Drivers of change, causalities and sustainable management strategies). Additional funding was provided by the German Academic Exchange Services (DAAD) through a fellowship program “special initiative, a world without hunger 2015,” awarded to DN through ILRI. The screening of samples for Coxiella burnetii was supported by the co-infection project (Co-infection with Rift Valley fever virus, Brucella spp. and Coxiella burnetii in humans and animals in Kenya: Disease burden and ecological factors) funded by the Defense Threat Reduction Agency (DTRA) (grant no. HDTRA 11910031).