Molecular prevalence and associated risk factors of Theileria annulata infections in dromedary camels in Egypt.

Abstract

Theileria annulata (T. annulata) is an intracellular protozoan, transmitted by ixodid ticks of the genus Hyalomma and affects camels. There are few epidemiological data on T. annulata infection and its associated risk factors in Egyptian camels. Thus, the present study aimed to determine the prevalence of T. annulata in camels using PCR and assess the associated risk factors for infection. A total of 380 blood samples were collected from camels raising in three Egyptian governorates and examined by PCR assay targeting 30-kDa gene to detect the presence of T. annulata infection, beside statistical analysis of associated factors. The results revealed presence of T. annulata with overall prevalence of 21.1%. In addition, the univariate analysis revealed significant (P<0.05) association between prevalence of T. annulata in camels and locality, age, sex, tick infestation, and application of acaricides. Whereas the prevalence of T. annulata was higher in camels of age group >6 to 10 years (38%), females (25.7%) and in infested camels with ticks (29%) and in case of absence of acaricides application (25%). In contrast, the body condition of camels had not significant effect on prevalence of theileriosis in camels. The current study concluded that T. annulata is prevalent in Egyptian camels and that a tick control program is required to reduce the risk of infection.