Cummulative Incidence and Molecular Characterization of Trypanosoma Species in Camel Population of Bahawalpur District, Pakistan

Abstract Trypanosomiasis is a serious problem that causes severe health and productivity issues in camels through Camel trypanosomiasis due to Trypanosoma evansi in arid areas. This study was a prospective, hospital-based study conducted May 2024 to April 2025 in the Bahawalpur district, province of Punjab, Pakistan. The present study aimed to calculate the cumulative incidence rate and molecular characterization of Trypanosoma evansi and to correlate the clinical signs with the camel population of Bahawalpur district. To our knowledge, this study presents the first-ever estimate of cumulative incidence based on the clinical signs of Trypanosoma evansi in camels globally and within Pakistan. With a 12-month risk of 0.71%, indicating approximately 7 new infections per 1,000 camels per year. Those eighty clinically suspected cases of trypanosomiasis in camels were subjected to microscopy and polymerase chain reaction (PCR) on ITS- 1 region. T. evansi was found in 5 percent (4/80) samples by microscopy and 8.75 percent (7/80) with PCR, making it less sensitive (57.14 percent) of microscopy and specificity of (100 percent). A statistical analysis showed strong correlations of infection and season (p = 0.040), age (p = 0.001), and body condition score (p = 0.000), and the infection was mostly prevalent in spring, camels younger than a year and emaciated. There was no significance association in sexes (p = 0.641). Concerning the clinical presentation, the co-occurrence of weight loss, anemia and fever and showed high correlation with infection of T.evansi. These evidences identify PCR as the diagnostic choice to establish accurate diagnosis especially in chronic and low-parasitemia infections. It is recommended to reduce the burden of camel trypanosomiasis in the region by using targeted control measures affecting young, undernourished camels and increasing year-round surveillance during high risk seasons.