Seroprevalence of Brucella spp. and Rift Valley fever virus among slaughterhouse workers in Isiolo County, northern Kenya

PLoS Negl Trop Dis. 2023 Oct 5;17(10):e0011677. doi: 10.1371/journal.pntd.0011677. eCollection 2023 Oct.

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 cross-sectional 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 ELISA-positive 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abattoirs
  • Animals
  • Antibodies, Viral
  • Brucella*
  • Cross-Sectional Studies
  • Humans
  • Kenya / epidemiology
  • Rift Valley Fever*
  • Rift Valley fever virus*
  • Seroepidemiologic Studies

Substances

  • Antibodies, Viral

Grants and funding

This study was implemented under the 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 Defense Threat Reduction Agency, (Grant No. HDTRA11910031 awarded to BB). The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. Additional funding was provided by the Consultative Group on International Agricultural Research (CGIAR) Fund Donors (https://www.cgiar.org/funders). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.