Epidemiological Status of Theileriosis and Babesiosis among Domestic Ruminants in West Azerbaijan Province, Iran: A Systematic Review and Meta-analysis

Background: Theileriosis and babesiosis are major tick-borne hemoprotozoan diseases of domestic ruminants associated with economic losses, including anemia, reduced productivity, reproductive disorders, and mortality. West Azerbaijan Province, northwestern Iran, is considered an endemic region for these infections because of favorable climatic conditions, extensive livestock farming, and transboundary animal movement. This systematic review and meta-analysis aimed to evaluate the epidemiological status and prevalence of theileriosis and babesiosis among domestic ruminants in this province.

Methods: A systematic search of English and Persian databases, including PubMed, Scopus, Web of Science, ScienceDirect, Google Scholar, SID, Magiran, IranMedex, and ElmNet, was conducted for studies published between 2000 and 2025. Studies reporting the prevalence of Theileria spp. and Babesia spp. infections in cattle, sheep, goats, and buffaloes in West Azerbaijan Province were included. Data on sample size, host species, diagnostic methods, parasite species, and prevalence rates were extracted. Meta-analysis was performed using a random-effects model with 95% confidence intervals. Heterogeneity was assessed using the I² statistic, and publication bias was evaluated through subgroup analyses and funnel plot assessment.

Results: A total of 19 eligible studies involving more than 10,000 domestic ruminants were included. Infection rates ranged from 10% to 50% depending on parasite species, host animal, and diagnostic method, with higher prevalence in sheep than cattle and goats. Theileria annulata, T. lestoquardi, T. ovis, and Babesia ovis were the predominant species identified. The prevalence of T. annulata, T. ovis, and B. ovis was estimated at 27.5%, 17.4%, and 13.9%, respectively. PCR-based methods demonstrated greater sensitivity than conventional microscopy.

Conclusion: West Azerbaijan Province represents an important endemic focus for theileriosis and babesiosis among domestic ruminants in Iran. Continuous epidemiological surveillance, integrated tick-control programs, and implementation of sensitive diagnostic approaches should be strengthened to reduce the economic and veterinary impacts of these infections on livestock production.