Prevalence and Risk Factors of East Coast Fever in the Copperbelt and Central Provinces of Zambia

Abstract

East Coast fever (ECF) is an infectious tick-borne disease of cattle, caused by a protozoan parasite Theileria parva. It is a disease of major economic importance in Zambia as it is the main cause of cattle morbidity and mortality. Despite its economic importance, the epidemiology of ECF in Zambia is poorly understood, thereby making ECF prevention and control difficult. Further, there is limited published literature on this disease in Zambia, with little available research concentrating on Southern and Eastern provinces. Such literature is mostly based on serological techniques such as indirect fluorescent antibody test (IFAT) which have limited sensitivity and specificity. Thus, this study was conducted to determine the prevalence and associated risk factors of ECF in Copperbelt and Central provinces of Zambia. The study was cross-sectional in design. Multistage cluster sampling was used involving district, veterinary camp, herd and individual animals. The provinces and districts were selected based on their vast potential for livestock production and the previously reported incidence of ECF. From each district, two veterinary camps were randomly selected. From each camp, herds were randomly selected from which individual animals were randomly sampled. Samples were collected from Mpongwe and Masaiti districts (Copperbelt province) and Kapiri Mposhi and Chibombo districts (Central province). Samples were examined for the presence of schizonts on Giemsa stained lymph smears. The lymph smear examinations revealed that 6.4% (95%, CI=4.9-7.9) of the samples were positive for T. parva schizonts. In Central province, the overall prevalence was 6.7% (95%, CI=4.0-8.2), while in the Copperbelt province it was 6.1% (95%, CI=4.0-8.2). Among the districts in these provinces, Kapiri Mposhi did not record any schizont positive cattle, while Masaiti recorded 2.4% (95%, CI=0.5-4.3). Mpongwe had a prevalence of 9.7% (95%, CI=6.0-13.4) and Chibombo had the highest prevalence at 13.6% (95%, CI=9.4-17.9). Risk factors that were identified to be associated with ECF were the district, frequency of veterinary service provision, tick control frequency, age and previous experience of ECF. The results indicate that ECF is prevalent in Copperbelt and Central provinces and hindering livestock production. There is hence the need for concerted efforts to control ticks and prevent ECF transmission through farmer sensitization, routine, regular, mandatory and supervised dipping and spraying of cattle and stringent livestock movement control.