Molecular epidemiology and phylogenetic analysis of Tams I gene of Theileria annulata in Khyber Pakhtunkhwa, Pakistan

Theileriosis is a hemoparasitic disease that affects a wide range of different animal species and is caused by various species of Theileria. This study aimed to determine the molecular epidemiology of Theileria annulata through microscopy and PCR, in crossbred cattle in some districts of Khyber Pakhtunkhwa, Pakistan. For this study, a total of 384 blood samples were collected from cattle in the Peshawar (n=120), Charsadda (n=94), Nowshera (n=84), and Swabi (n=86) districts. Microscopy and PCR were used to determine the overall prevalence of theileriosis, which was found to be 15.8 and 22.6%, respectively. Theileria annulata was detected in blood samples through PCR in the study area, and the target gene i.e., Tams 1, of positive samples was sequenced. The sequences in the current study revealed high sequence homology (ranging from 96 to 100%) with Tams 1 sequences of neighboring countries present in the NCBI database. Season, breed, age, and sex were found to be important risk factors among the several risk factors examined, whereas, among different clinical manifestations, lymphadenopathy showed a strong association with theileriosis. According to Cohen's kappa and ROC analysis, microscopy was proven to be a fair diagnostic test for detecting theileriosis in cattle, and may be used in combination with molecular techniques for screening a large number of animals.