Abstract:
Brucella spp. and Rift Valley fever virus (RVFV) are classified as priority zoonotic agents in
Kenya, based on their public health and socioeconomic impact on the country. Data on the
pathogen-specific and co-exposure levels is scarce due to limited active surveillance. This
study investigated seroprevalence and co-exposure of Brucella spp. and RVFV and associated
risk factors among slaughterhouse workers in Isiolo County, northern Kenya. A crosssectional
serosurvey was done in all 19 slaughterhouses in Isiolo County, enrolling 378 participants
into the study. The overall seroprevalences for Brucella spp. and RVFV were
40.2% (95% CI: 35.2–45.4) and 18.3% (95% CI: 14.5–22.5), respectively while 10.3% (95%
CI 7.4%-13.8%) of individuals were positive for antibodies against both Brucella spp. and
RVFV. Virus neutralisation tests (VNT) confirmed anti-RVFV antibodies in 85% of ELISApositive
samples. Our seroprevalence results were comparable to community-level seroprevalences
previously reported in the area. Since most of the study participants were not
from livestock-keeping households, our findings attribute most of the detected infections to
occupational exposure. The high exposure levels indicate slaughterhouse workers are the
most at-risk population and there is need for infection, prevention, and control programs
among this high-risk group. This is the first VNT confirmation of virus-neutralising antibodies
among slaughterhouse workers in Isiolo County and corroborates reports of the area being
a high-risk RVFV area as occasioned by previously reported outbreaks. This necessitates
sensitization campaigns to enhance awareness of the risks involved and appropriate mitigation
measures.
