Seroprevalence of Peste des Petits Ruminants Virus Antibodies and Associated Factors in Small Ruminants Sampled Around Protected Wildlife Areas in Pakistan

Peste des Petits Ruminants (PPR) threatens small-ruminant production in Pakistan, particularly where livestock grazing overlaps with wildlife habitats. In this exploratory cross-sectional study (January–June 2024), 1939 sera from goats (n = 1327) and sheep (n = 612) in 56 herds, purposively selected near eight protected wildlife areas, were tested for antibodies against PPR virus (PPRV) using a competitive ELISA. Vaccinated and unvaccinated animals were included, and the assay cannot distinguish vaccine-induced from infection-induced antibodies. The overall apparent antibody seroprevalence was 38.5% (747/1939; 95% CI: 36.4–40.7%) (naive 95% CI; it ignores clustering and understates uncertainty, and between-site heterogeneity was very high, I2 = 94%), ranging from 16.7% in Peshawar to 73.0% at Kirthar National Park, Sindh. Crude odds of seropositivity were higher in goats than in sheep (44.8% vs. 25.0%; OR = 2.43, 95% CI: 1.97–3.01), in animals older than three years than in those aged > 1–3 years (52.0% vs. 33.8%; OR = 2.13, 95% CI: 1.69–2.67), and in herds with more than 100 animals than in herds with 50–100 animals (43.3% vs. 35.7%; OR = 1.38, 95% CI: 1.11–1.72). After adjustment for site, goats remained more likely to be seropositive than sheep (OR = 2.19, 95% CI: 1.76–2.74), although the species difference varied between sites (heterogeneity p = 0.005). Herd-level clustering could not be modelled; associations with herd-level factors (herd size, vaccination status) were sensitive to plausible within-herd correlation and are exploratory. Vaccination categories are reported descriptively only. PPRV antibodies were common in small ruminants sampled near the selected protected areas. However, wildlife were not sampled, distance categories were confounded with site, and results are not nationally representative; transmission at the livestock–wildlife interface was not demonstrated. Targeted surveillance and integrated livestock–wildlife studies are warranted.