The Burden of Theileria Infections in Animals Across the Arabian Gulf: A Systematic Review

Theileriosis is a tick-borne disease that threatens livestock health and productivity, particularly in regions with climates favorable to tick survival. In the Arabian Gulf, environmental conditions and extensive animal management increase risk, yet available data are limited and fragmented. This systematic review synthesizes existing evidence on the prevalence, species diversity, and risk factors of Theileria infections to inform surveillance and control strategies in the region. A literature search was conducted in Google Scholar, ScienceDirect, and PubMed following PRISMA guidelines. Studies reporting Theileria infection in animals from the Arabian Gulf were included. Data were extracted, and the quality and potential bias of each study were evaluated using the JBI checklist. From an initial 6,211 records, 42 studies were included after screening, with the majority conducted in Saudi Arabia, Oman, the UAE, and Qatar. The studies revealed significant variability in the prevalence, species diversity, host range, diagnosis, and vector involvement related to Theileria infections, with prevalence rates ranging from 0% to 100%. Cattle, sheep, goats, and camels were the most extensively studied hosts, with molecular techniques revealing higher prevalence rates and uncovering subclinical infections often missed by microscopy. Notably, multiple Theileria species, such as T. annulata, T. lestoquardi, T. ovis, and T. equi, were identified, with wildlife species also acting as reservoirs. Risk factors associated with infection included tick exposure, animal movement, management practices, and environmental conditions. Overall, the findings highlight the complex dynamics of Theileria in the region and the need for targeted surveillance and control measures.