Seroprevalence of foot-and-mouth disease in large ruminants in periurban dairy farms near Islamabad, Pakistan

Abstract

Abstract Background Foot-and-mouth disease (FMD) is an enzootic viral disease affecting livestock in Pakistan. Objectives To determine the seroprevalence of FMD in large ruminants in periurban dairy farms near Islamabad. Methods Serum samples were collected from 636 large ruminants during 2011 to 2012; 584 (92%) were buffaloes (Bos bubalis bubalis) and 52 (18%) were cattle (Bos taurus indicus). The population sampled was mainly adult (n = 514) and female (n = 596). Sera were assayed for antibodies against a nonstructural protein of the FMD virus using a Chekit FMD-3ABC bo-ov enzyme immunoassay Kit (Idexx Laboratories). Data were analyzed using a χ2 test and multiple logistic regression. Results The seroprevalence of FMD in the ruminants was 46% (n = 293, 95% confidence interval (CI); 42.18- 49.95) and was significantly higher in buffaloes (285, 97%; χ2 = 21.46; P < 0.001) than in cattle (8, 3%). The risk of seropositivity increased significantly with age (χ2 = 72.71; P < 0.001); adult animals were 7.05 times more likely (odds ratio (OR) 7.05, 95% CI 3.60-13.79; P < 0.001) to be seropositive after adjusting for the effect of species. Buffaloes were more likely to be seropositive (OR 3.99, 95% CI 1.78-8.92, P = 0.001). Sex was not significantly associated with FMD seropositivity (OR 0.58, 95% CI 0.17-1.95, P = 0.38). Conclusions Large ruminants in periurban dairy farms near Islamabad have a high FMD virus seroprevalence and play a potential role in the persistence and transmission of FMD in Pakistan.