Borana women with sheep and goats at a traditional deep well water source, Garba Tulla, Isiolo, Kenya (photo credit: ILRI/Fiona Flintan).

Brucellosis is an important zoonotic disease that affects wildlife and livestock. People may get exposed to the disease through direct contact with an infected animal or consumption of raw or undercooked animal products. In humans, the disease is characterized by prolonged fever, body aches, joint pains and weakness, while in livestock, it mainly causes abortions and infertility. 

A study carried out in Garissa and Tana River counties of Kenya set out to identify the factors that affect the spread of brucellosis in people and livestock. Livestock and people from randomly selected households were recruited and serum samples were obtained and screened for Brucella antibodies to determine the level of exposure to Brucella spp. 

The study found that the chances of exposure to brucellosis in humans were at least three times higher in households that had at least one Brucella-seropositive animal compared to those that had none. 

This finding can be used to design risk-based surveillance systems for brucellosis, based on the locations of the primary cases of the disease, where each case of Brucella infection identified in livestock could signal potential locations of additional brucellosis cases in humans, and vice versa.

Citation

Kairu-Wanyoike, S., Nyamwaya, D., Wainaina, M., Lindahl, J., Ontiri, E., Bukachi, S., Njeru, I., Karanja, J., Sang, R., Grace, D. and Bett, B. 2019. Positive association between Brucella spp. seroprevalences in livestock and humans from a cross-sectional study in Garissa and Tana River Counties, Kenya. PLOS Neglected Tropical Diseases 13(10): e0007506.