Seroprevalence and risk factors of Mycobacterium avium subsp. paratuberculosis in dromedary camels of Southern Punjab, Pakistan.

Mycobacterium avium subspecies paratuberculosis (MAP) is the etiologic agent of paratuberculosis (Johne's disease), a chronic granulomatous enteritis. A cross-sectional survey was conducted between 2022 and 2023 to determine the seroprevalence of MAP and identify associated risk factors in dromedary camels sampled in southern Punjab, Pakistan. Sera were tested using a commercial indirect ELISA (ID Screen® Paratuberculosis Indirect Screening Test, ID VET, Montpellier, France). The overall seroprevalence was 3.31% (20/604), and the Rogan-Gladen estimator yielded a true prevalence of 4.13%. The highest tehsil-level prevalence was recorded in Bahawalpur (6.3%), followed by Yazman (3.4%) and Liaqat Pur (1.96%). Multivariate logistic regression identified diarrhea (OR = 8.39, 95% CI: 2.46-28.59%, p = 0.001) and a history of abortion (OR = 6.75, 95% CI: 1.70-26.81, p = 0.007) as significant predictors of MAP seropositivity; sex, age, breed, body condition score (BCS), and contact with other ruminants remained non-significant. These findings provide sero-epidemiological evidence of MAP in camels in Southern Pakistan and highlight the need to strengthen the surveillance, coupled with molecular diagnostics, for early detection and control.