Diseases of Importance at the Wildlife/Livestock Interface in Kenya1

Wildlife and livestock contribute significantly to the economies of most sub-Saharan African countries. The wildlife sector in Africa is worth US $7 billion with an annual growth rate of 5%. It is thus a major contributor to the continental gross domestic product (GDP). In East and southern African countries, the consumptive and nonconsumptive utilization of wildlife is a significant foreign exchange earner. In Kenya, tourism accounts for 30% of foreign exchange earnings (Kock et al. 2002). The livestock subsector contributes over 30% of the agricultural GDP and employs more than 50% of the agricultural labor force. Dairy and livestock farming accounts for utilization of 30% of the high-to-medium-potential land and of 81% of the arid and semi-arid lands and is crucial for promoting rural development and reducing poverty (Kock et al. 2002). The rangelands of Kenya comprise 74% of the country’s land area and are largely inhabited by nomadic or transhumant pastoralists who comprise 25% of the total population and are principally dependent on livestock (Bourn and Blench 1999). Most of Kenya’s livestock and most wildlife are found in the rangeland districts of Kajiado, Laikipia, Narok, and Taita Taveta (Bourn and Blench 1999), and this extensive traditional production system allows a greater interface between domestic and wild animals. The resurgence of some livestock and wildlife diseases in Kenya that were previously controlled is of serious concern. The recent incursion of rinderpest virus in Kenyan wildlife populations, associated with cattle in the Somali ecosystem, is one example (Wambwa 2002). Major factors in the spread of disease are the uncontrolled or illegal movements of livestock by pastoralists within the country and across national borders in search of grazing or markets, or as a result of cattle rustling. The cross-border livestock trade involves approximately 400,000 head of cattle per year. Seasonal wildlife movements result in frequent interactions with livestock, which also increases the possibility of disease spread across boundaries (Wambwa 2002). In addition, most of these rangelands have a poor infrastructure and are remote, making it difficult to provide adequate veterinary services. The diseases of major concern to livestock trade presently include contagious bovine pleuropneumonia, contagious caprine pleuropneumonia, African swine fever, foot and mouth disease, Rift Valley fever, rinderpest, and peste des petits ruminants (Grootenhuis 1999). Other diseases of economic and public health importance in Kenya include viral diseases such as malignant catarrhal fever and rabies (Karstad 1986, Kock et al. 2002), bacterial diseases such as anthrax and brucellosis (Karstad 1986), protozoal diseases such as trypanosomiasis and theileriosis, and ectoparasite and helminth infestations (Grootenhuis 1986). The presence of transboundary diseases has greatly reduced Kenya’s export of wildlife, livestock, and their products to lucrative international markets as a result of the stringent requirements in sanitary standards for international trade in animals and animal products established by the World Organisation for Animal Health (OIE). This paper briefly describes the wildlife/livestock interface in Kenya, with emphasis on the important animal diseases at this interface. It suggests measures to enhance disease control and improve trade in wildlife, livestock, and their products.