Incidence of Morbidity, Mortality and Risk Factors Associated With East Coast Fever and Theileria Parva Infection in Calves in Narok County, Kenya

Abstract

The livestock sector in Kenya is an important source of livelihood to a large proportion of pastoral households and therefore it plays a significant role in poverty reduction strategies for the rural populations. Similarly, the urban population relies directly or indirectly on this sector through the sale of food animals or their products, or employment in livestock-related agro-processing industries. Cattle are the main source of milk and meat consumed in Kenya. Apart from the economic aspects, cattle are also kept for cultural and social values by the pastoral communities. Despite the immense contribution of cattle to the economy, they are faced with many challenges including animal diseases. Ticks and tick-borne diseases (TBDs) have been reported as the main constraint to cattle production in the tropics. Among these TBDs, East Coast fever, caused by Theileria parva has been ranked as the most significant tick-borne disease with huge economic losses and high mortality killing approximately one million cattle annually. The study was carried out to understand the current epidemiology of ECF to help improve control and preventive measures. This study described the characteristics of production systems in different agroecological zones of Narok County of Kenya, estimated the seroprevalence of Theileria parva infection in calves less than one month, investigated the incidence of morbidity and mortality of East Coast fever and Theileria parva infection and the associated risk factors among calves in Narok County. The activities were undertaken from two wards of Ololulung’a and Naroosura Maji Moto of Narok South sub-county between May 2022 and December 2023. Initially, a crosssectional survey was undertaken to capture the baseline data on cattle husbandry and management practices and later a longitudinal study where calves were recruited and visited every 6 weeks for one year. During each visit, blood samples were collected, processed and stored at -200C in Narok and latter transported to Nairobi and stored at -400C awaiting serological analysis. Similarly, semixviii structured questionnaires, uploaded on CommCare platform, were administered at every visit to capture information on the health and management of the recruited calves.