Epidemiology of tropical bovine theileriosis (Theileria annulata infection) in Tunisia: A review

Abstract

This article reviews the literature on the epidemiology of tropical theileriosis in Tunisia. It is a specific parasitic disease caused by the presence and proliferation in mononuclear phagocytes, then in erythrocytes of a protozoan belonging to the family Theileridae, Theileria annulata. It is biologically transmitted by several species of ixodid ticks belonging to the genus Hyalomma. The three actors involved have a very different taxonomy causing a disease whose epidemiology is particularly complex. This infection consists of three enzootic ways: enzootic stability due to an equilibrium between the host and the parasite, (ii) low enzootic instability due to the presence of a low tick population causing clinical cases in animals aged 2 to 3 years, and (iii) high enzootic instability in which the tick population is so low that the probability of a contact between an infected tick and a susceptible host is very low. Depending on the epidemiological situation, the farms can plan adapted control programs.