Evidence of exposure to C. burnetii among slaughterhouse workers in western Kenya

Elizabeth Anne Jessie Cook; William Anson de Glanville; Lian Francesca Thomas; Alice Kiyong'a; Velma Kivali; Samuel Kariuki; Barend Mark de Clare Bronsvoort; Eric Maurice Fèvre

doi:10.1016/j.onehlt.2021.100305

Evidence of exposure to C. burnetii among slaughterhouse workers in western Kenya

One Health. 2021 Aug 10:13:100305. doi: 10.1016/j.onehlt.2021.100305. eCollection 2021 Dec.

Authors

Affiliations

¹ International Livestock Research Institute, Old Naivasha Road, PO Box 30709, 00100 Nairobi, Kenya.
² Center for One Health, University of Global Health Equity, Rwanda.
³ Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK.
⁴ Kenya Medical Research Institute, PO Box 19464-00200, Nairobi, Kenya.
⁵ Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK.
⁶ Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK.

Abstract

Q fever, caused by C. burnetii, has been reported in slaughterhouse workers worldwide. The most reported risk factor for seropositivity is the workers' role in the slaughterhouse. This study examined the seroprevalence and risk factors for antibodies to C. burnetii in slaughterhouse workers in western Kenya to fill a data gap relating to this emerging disease in East Africa. Individuals were recruited from all consenting slaughterhouses in the study area between February and November 2012. Information was collected from participating workers regarding demographic data, animals slaughtered and role in the slaughterhouse. Sera samples were screened for antibodies to C. burnetii using a commercial ELISA and risk factors associated with seropositivity were identified using multi-level logistic regression analysis. Slaughterhouse workers (n = 566) were recruited from 84 ruminant slaughterhouses in western Kenya. The seroprevalence of antibodies to C. burnetii was 37.1% (95% Confidence Interval (CI) 33.2-41.2%). The risk factors identified for C. burnetii seropositivity included: male workers compared to female workers, odds ratio (OR) 5.40 (95% CI 1.38-21.22); slaughtering cattle and small ruminants compared to those who only slaughtered cattle, OR 1.52 (95% CI 1.06-2.19). In addition, specific roles in the slaughterhouse were associated with increased odds of being seropositive, including cleaning the slaughterhouse, OR 3.98 (95% CI 1.39-11.43); cleaning the intestines, OR 3.24 (95% CI 1.36-7.73); and flaying the carcass OR 2.63 (95% CI 1.46-4.75) compared to being the slaughterman or foreman. We identified that slaughterhouse workers have a higher seroprevalence of antibodies to C. burnetii compared to published values in the general population from the same area. Slaughterhouse workers therefore represent an occupational risk group in this East African setting. Workers with increased contact with the viscera and fluids are at higher risk for exposure to C. burnetii. Education of workers may reduce transmission, but an alternative approach may be to consider the benefits of vaccination in high-risk groups.

Keywords: C. burnetii; Kenya; Occupational health; Q fever; Slaughterhouse; Zoonoses.

Abstract

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