"Silent circulation of Trichinella spp. in wild boars (Sus scrofa): Evidence from serology in the absence of detectable larvae".

Trichinella spp. are globally distributed foodborne zoonotic parasites maintained in complex sylvatic cycles, with wild boars (Sus scrofa) serving as key reservoir hosts. Regions located at ecological crossroads, where wildlife movement and species interactions are intensified, may facilitate silent parasite circulation that remains undetected by conventional surveillance. Türkiye, situated at the interface between Europe and Asia, and particularly the Central Black Sea Region-characterised by major river systems, wetland deltas, and migratory bird flyways-represents such a high-connectivity ecological landscape. In this study, exposure to Trichinella spp. was investigated in 100 wild boars hunted in Samsun, Amasya, and Çorum provinces using an integrated diagnostic approach combining parasitological, serological, and molecular methods. Muscle tissues were examined by magnetic stirrer artificial digestion and trichinoscopy, while meat juice samples were analysed for anti-Trichinella antibodies using a commercial multi-species indirect ELISA. Conventional PCR targeting the mitochondrial cytochrome c oxidase subunit I (COI) gene was performed on tissues from seropositive animals. No Trichinella larvae or parasite DNA were detected by direct or molecular methods. In contrast, serological analysis revealed a high apparent seroprevalence (24%; 95% CI: 16.7-33.2%). However, considering the potential for ELISA to overestimate prevalence due to cross-reactivity with other helminths, these results indicate widespread exposure rather than confirmed active infection. The presence of anti-Trichinella antibodies in the absence of detectable larvae indicates previous exposure, low-intensity infections, or latent infection dynamics within the wild boar population. These findings indicate that wild boars in the Central Black Sea Region of Türkiye are exposed to Trichinella spp. despite the absence of detectable larvae by conventional parasitological and molecular methods. The observed discrepancy between serological and direct detection results demonstrates a pattern of silent circulation of Trichinella spp. within a highly connected wildlife landscape and highlights the limitations of relying solely on direct detection methods for surveillance. Integrating serological tools paired with confirmatory testing, such as Western blot, into wildlife monitoring programmes is therefore essential for accurately assessing parasite circulation and for improving the evaluation of potential spillover risks at the human-wildlife interface.