Seroprevalence and Risk Factors Analysis of Foot‐and‐Mouth Disease in Cattle and Buffaloes in Punjab of Pakistan: A 3ABC ELISA‐Based Study

Foot‐and‐mouth disease (FMD) is an important transboundary livestock disease that can cause significant economic losses in endemic areas. This study aimed to assess the seroprevalence of antibodies against the nonstructural proteins (NSPs) of FMD virus (FMDV) and associated animal‐ and farm‐level risk factors in cattle and buffaloes of nine livestock‐producing districts in Punjab, Pakistan. A 6‐month field survey was conducted in which a total of 576 animals (322 cattle and 254 buffaloes) were sampled, and a 3ABC ELISA was used. The assay measures antibodies to FMDV NSPs, supporting a DIVA (differentiation of infected from vaccinated animals) strategy, as NSP antibodies are more characteristic of viral replication than vaccination with purified inactivated vaccines. However, vaccination histories were not available for the sampled animals, and NSP seropositivity in this study was regarded as indicative of prior FMDV exposure, with the possibility of residual NSPs in incompletely purified vaccines acknowledged. Overall FMDV NSPs seropositivity was 71.18% (410/576), ranging from 33.33% in Kasur to 89.36% in Faisalabad. The NSP seropositivity was higher in cattle (75.16%) than in buffaloes (66.14%), but the difference was not statistically significant (odds ratio [OR] = 1.14, 95% confidence interval [CI]: 0.88–1.47; p = 0.3289). The odds of seropositivity were higher in female animals than in male animals (74.72% vs. 26.19%; OR = 2.85, 95% CI: 1.46–5.58; p = 0.0016), but this should be interpreted with caution because of the highly skewed sex distribution. Animals over 10 years old were more likely to be FMDV NSPs seropositive than animals ≤5 years old (OR = 1.96, 95% CI: 1.24–3.08; p = 0.0085). Cattle–sheep mixed‐species contact was also associated with higher NSP seropositivity (90.91%; OR = 2.73, 95% CI: 1.53–4.85; p = 0.0417). These results suggest significant FMDV exposure in the sampled livestock population and emphasize the need for risk‐based surveillance, farm animal‐movement management, and enhanced farm biosecurity for FMD control in Punjab.