Hepatitis E virus (HEV) causes infections in humans and a wide range of animal hosts. Wild boar is an important natural reservoir of HEV genotypes 3–6 (HEV-3–HEV-6), but comparative analysis of HEV infections in both feral and farmed wild boars remains limited. In this study, samples from 599 wild boars were collected during 2017–2020, including 121 feral wild boars (collected 121 fecal, 121 serum, and 89 liver samples) and 478 farmed wild boars (collected 478 fecal and 478 serum samples). The presence of anti-HEV IgG antibodies were detected by the HEV-IgG enzyme-linked immunosorbent assay (ELISA) kit. HEV RNA was detected by reverse transcription polymerase chain reaction (RT-PCR), targeting the partial ORF1 genes from fecal and liver samples, and the obtained genes were further genotyped by phylogenetic analysis. The results showed that 76.2% (95% CI 72.1–79.9) of farmed wild boars tested anti-HEV IgG seropositive, higher than that in feral wild boars (42.1%, 95% CI 33.2–51.5, p < 0.001). HEV seropositivity increased with age. Wild boar HEV infection presented a significant geographical difference (p < 0.001), but not between sex (p = 0.656) and age (p = 0.347). HEV RNA in fecal samples was detected in 13 (2.2%, 95% CI 1.2–3.7) out of 599 wild boars: 0.8% (95% CI 0.0–4.5, 1/121) of feral wild boars and 2.5% (95% CI 1.3–4.3, 12/478) of farmed wild boars. Phylogenetic analysis showed that all these viruses belonged to genotype HEV-4, and further grouped into sub-genotypes HEV-4a, HEV-4d, and HEV-4h, of which HEV-4a was first discovered in the wild boar populations in China. Our results suggested that farms could be a setting for amplification of HEV. The risk of HEV zoonotic transmission via rearing and consumption of farmed wild boars should be further assessed.

Wild ruminants are at risk for zoonotic pathogen infection as a result of interactions with domestic animals and humans. One way to assess the level of a wild ruminant disease in a population is to determine the seroprevalence of the pathogen of interest. The objective of this study was to determine the seroprevalence of five zoonotic pathogens in wild ruminants in Xinjiang, Northwest China. In 2009 and 2011–2015, 258 wild ruminant sera samples were collected from various species. Samples were obtained from 30 Siberian ibexes, 94 goitered gazelles, 6 Tibetan antelopes, 32 argali sheep, 16 roe deer, 20 blue sheep, 56 red deer, and 4 wild yaks, in 10 regions of Xinjiang. Samples were tested using antibodies against Brucella spp ., Chlamydophila abortus , Coxiella burnetii , Toxoplasma gondii , and West Nile virus. Seropositivity was detected for all five pathogens, with detection rates of Brucella spp ., C. abortus , C. burnetii , T. gondii , and West Nile virus of 2.3% (95% confidence interval [CI], 0.5–4.2%), 6.2% (95% CI, 3.3–9.1%), 7.8% (95% CI, 4.5–11.0%), 2.3% (95% CI, 0.5–4.2%), and 0.8% (95% CI, 0–1.8%), respectively. The level of pathogens differed for different species and different regions. The results indicate that seropositivity to zoonotic pathogens is common among wild ruminants in Xinjiang, Northwest China, with C. burnetii and C. abortus detected at the highest levels. This study provides a baseline for future assessment of spillover events.

Background: Tuberculosis (TB), caused by Mycobacterium tuberculosis complex (MTBC), poses a significant risk for zoonotic transmission, especially with the increasing wild boar population in China. Following the annual wildlife disease surveillance, we conducted a serosurvey to determine the prevalence of TB in wild boars. We collected 512 serum samples from 25 counties of Xinjiang, Northwest China, and used ELISA to detect antibodies against bPPD. TB seropositivity was defined as a mean sample OD450nm ≥ 2×the mean negative control OD450nm, and employed cluster analysis with purely spatial scan statistics using the Bernoulli model. Results: The seropositivity was 10.0% (51/512), with higher rates in farmed wild boars (12.0%, 47/391) than feral wild boars (3.3%, 4/121), indicating a greater risk in farmed wild boar populations. Spatial analysis revealed two clusters near the Sino-Kazakh border, underscoring the need for targeted surveillance and control measures to prevent zoonotic transmission. Conclusion: Xinjiang is a endemic area for MTBC exposure, with farmed wild boars posing higher risk. Findings highlight the need for targeted surveillance, control measures, and international collaboration to prevent zoonotic transmission.