CIGH slaughterhouse study data

Rift Valley Fever virus (RVFV) is a globally important zoonotic arbovirus that is endemic across Africa with potential to cause severe disease in livestock and humans. Viral spread is primarily driven by livestock movement and despite influx of livestock to urban areas in response to the high demand for meat and animal products, RVFV has not been detected in any urban center. The objectives of this study were to determine the feasibility of assessing risk of transmission to urban Kisumu, Kenya, by testing slaughtered livestock for RVFV exposure and mapping livestock origins. Blood was collected from cattle, sheep, and goats directly after slaughter and tested for anti-RVFV antibodies. Slaughterhouse businessmen responded to a questionnaire on individual animals’ origin, marketplace, and transport means. Thereafter, livestock flow from origin to slaughterhouse was mapped using participatory mapping methods in focus group discussions with stakeholders. Qualitative data on route choice and deviations were spatially integrated into the map. A total of 304 blood samples were collected from slaughtered livestock in October and November 2021 and 99% of animals were purchased from 28 different markets across eight counties in Western Kenya. The overall RVFV seroprevalence was 9% (19% cattle, 3% in sheep, and 7% in goats). Migori County bordering Tanzania had the highest county-level seroprevalence (34%) and 80% of all seropositive cattle were purchased at the Subakuria market. Road quality and animal health influenced stakeholders’ decisions for transport means. Overall, this proof-of-concept study offers a novel sampling framework that can be locally implemented and rapidly deployed in response to increased regional risk. This information can be used in conjunction with participatory maps to improve active livestock surveillance for RVFV in Western Kenya and methods could be extrapolated to other urban centers and provide a basis for improved monitoring of RVFV and other livestock diseases.