Treatment of contagious bovine pleuropneumonia as a potential driver for antimicrobial resistance in pastoral production systems of Kenya.

The control of contagious bovine pleuropneumonia (CBPP) remains constrained by institutional, financial and technical barriers in many livestock-keeping regions of sub-Saharan Africa, despite its detrimental impact on trade, pastoral livelihoods and food security. Therefore, livestock keepers are relying on suboptimal use of antimicrobials to manage CBPP outbreaks. We conducted an outbreak investigation to understand epidemiological and management practices in 95 herds with ongoing or recent cases of CBPP in five counties of Kenya. A wide range of antimicrobials including tetracycline, penicillin-streptomycin (pen & strep), tylosin, and diminazen were used in majority of herds (90/95; 94.7%), with half of these herds receiving sequential administration of two or more types of drugs to address failure of the first use. Only 33/95 (34.7%) of farmers reported to have vaccinated their animals and most of them vaccinated in response to outbreaks in their herds rather than the expected routine preventive program (28/33, 84.8%). The average case fatality rate (CFR) for CBPP was estimated at 36%, with only treatment with tylosin resulting in a significant reduction in mortalities due to CBPP (p = 0.035). Majority of livestock keepers (83.3%) continued to consume milk from their animals during and after the treatment period, without observing the stipulated withdrawal periods. Policy emphasis should shift toward prudent use of antimicrobials and preventive vaccination as the cornerstone of CBPP control, while using multifaceted One Health strategy that bridges veterinary, public health, and environmental sectors.