PAKISTAN VETERINARY JOURNAL

Pak Vet J, 2026, 46(6) 1536-1544

Epidemiology and Diagnostic Performance of Theileria equi Infection in Equids: a Multi-Method Study with Climatic and Management Risk Factors in Selected Districts of Central Punjab, Pakistan

Qasim Bilal¹, Muhammad Shuaib Khan^*1, Muhammad Irfan², Shakeeb Ullah^1,3,4, Faiqah Ramzan¹, Babar Maqbool⁵, Ali Haider Saleem^6,7, Muzammal Tariq⁸, Farhan Farooq^9,10and Raja Danish Muner^*11

¹Faculty of Veterinary and Animal Sciences, Gomal University, Dera Ismail Khan, Pakistan; ²Department of Biotechnology, University of Sargodha, Pakistan; ³University of Veterinary and Animal Sciences, Swat, Pakistan; ⁴Pakistan Veterinary Medical Council, Islamabad, Pakistan; ⁵Department of Veterinary Medicine, Faculty of Veterinary and Animal Sciences, University of Agriculture Dera Ismail Khan, Pakistan; ⁶Department of Animal Sciences, University of Veterinary and Animal Sciences, sub-campus Jhang, Pakistan; ⁷Department of Animal Sciences, Purdue University, West Lafayette, Indiana, USA; ⁸Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture, Peshawar, Pakistan; ⁹Department of Poultry Sciences, PMAS Arid Agriculture University, Rawalpindi, Pakistan; ¹⁰World's Poultry Science Association, Pakistan; ^*11Department of Animal Breeding and Genetics, Faculty of Veterinary and Animal Sciences, University of Agriculture Dera Ismail Khan, Pakistan

*Corresponding author: danishmunirraja@gmail.com (RDM); shoaibbaloch2002@yahoo.com (MSK)

Abstract

This study provides insights into multi-method epidemiological dynamics and performance of diagnostic tests in horses with associated risk factors of theileriosis. We analyzed 1,414 blood samples collected monthly over one year across multiple regions, assessing seasonal trends, geographical variations, environmental drivers, and diagnostic performance. Overall, microscopy detected Theileria equi in 8.42% of samples, ELISA seroprevalence was 19.3%, and PCR confirmed infection in 14.4%. qPCR peaks were observed in March (30.0%; 95% CI: 22.6–38.6%) and October (26.4%; 95% CI: 19.1–35.3%), whereas the lowest prevalence was recorded in April (4.7%; 95% CI: 2.4–9.0%). Seasonally, the highest prevalence occurred in fall (20.1%) and spring (12.8%), both significantly higher than winter (7.8%; P<0.001). Geographically, MBD/Head Faqerian (28.3%; 95% CI: 21.9–34.7%) and Sargodha (27.2%; 95% CI: 20.9–33.5%) were identified as major hotspots of prevalence. Beta regression revealed temperature as key predictor with 0.69% increase per 1°C increase (P<0.001), While high humidity (>60%) and heat waves increased the risk by 0.22% and 1.98%, respectively. The Bayesian latent class model estimated the sensitivity and specificity of PCR at 86.2% and 94.5%, respectively, while ELISA showed a sensitivity of 78.5% and specificity of 88.2%. Microscopy demonstrated comparatively lower sensitivity (65.4%) but higher specificity (96.1%). In conclusion, theileriosis revealed strong association with climate-density interactions, spring/fall peaks and rapidly increasing transmission. The study recommends adopting pre-peak acaricide treatments in March and October, managing hotspot density, and using dual ELISA/PCR testing to enhance accuracy in mitigating this issue

To Cite This Article: Bilal Q, Khan MS, Irfan M, Ullah S, Ramzan F, Maqbool B, Saleem AH, Tariq M, Farooq Fand Muner RD, 2026. Epidemiology and diagnostic performance of Theileria equi infection in equids: a multi-method study with climatic and management risk factors in Selected Districts of Central Punjab, Pakistan. Pak Vet J, 46(6): 1536-1544. http://dx.doi.org/10.29261/pakvetj/2026.145

Abstract

ISSN 0253-8318 (Print)ISSN 2074-7764 (Online)

ISSN 0253-8318 (Print)
ISSN 2074-7764 (Online)