Trichinellosis is a foodborne disease caused by ingestion of raw or undercooked meat containing Trichinella spp. larvae. Consumption of wild boar (Sus scrofa) meat represents an important source of human trichinellosis worldwide. In El Palmar National Park (EPNP), Argentina, invasive alien wild boars are controlled and meat from culled animals is released for public consumption following on-site artificial digestion (AD) testing. Meat trimmings and offal from the control program are often used as food for dogs (Canis familiaris). We evaluated infection and exposure to Trichinella spp. in wild boars from EPNP, as well as exposure to Trichinella spp. and associated risk factors in dogs and human consumers of wild boar meat. Trichinella spp. larvae were detected in muscle samples from 5/49 wild boars by AD (10.2%; 95% confidence interval [CI], 3.8%–23%), with a mean burden of 0.24 larvae per gram (lpg; range, 0.06–0.95 lpg). Anti-Trichinella antibodies were not detected in wild boar serum samples (n=42). In dogs, 12/34 were seropositive to Trichinella spp. (35.29%; 95%, CI, 20.3%–53.5%). Immunoglobulin (Ig) G antibodies were not detected in human serum samples (n=63). Our results reveal the presence, albeit at low prevalence, of Trichinella spp. in wild boars and exposure in dogs fed game offal. These findings suggest that the low prevalence and parasitic load in wild boars, together with the best practices applied by EPNP culling program personnel, contribute to keeping the risk of infection in people low. The dog results highlight that the parasite is circulating in the area, and therefore the risk of infection is not negligible. We recommend the implementation of an animal surveillance strategy in order to monitor the evolution of this zoonosis in the study area.

Brucellosis is a worldwide zoonotic disease caused by Brucella spp. and transmitted from domestic and wild animals to humans. Brucellosis causes important economic losses in livestock, has a significant impact on public health, and may affect the health of wildlife. Hunting and consumption of meat from culled wildlife constitute a risk for Brucella spp. infection in humans and hunting dogs. In El Palmar National Park (EPNP), Argentina, the invasive alien mammals wild boar (Sus scrofa) and axis deer (Axis axis) are controlled, slaughtered in situ, and consumed by hunters, with meat trimmings and offal often fed to dogs. In this study, we evaluated but did not detect anti-Brucella antibodies in wild boar (n=95) and axis deer (n=238) from EPNP or in game consumers, dogs (n=39) and humans (n=61). These results suggest a lack of exposure to Brucella spp. at this site during the study period. Despite negative findings in the sampled location, One Health surveillance across multiple species contributes to our understanding of pathogen dynamics and enables targeted interventions to minimize health risks.

The hepatitis E virus (HEV) is an emerging multi-host pathogen, with suids being the main reservoir. Humans are primarily infected through the consumption of contaminated water or food. In Argentina, HEV circulation has been confirmed in humans, domestic pigs, wild boar (Sus scrofa), and surface water. In El Palmar National Park, invasive wild boar and axis deer (Axis axis) are controlled, and their meat is released for public consumption, with trimmings and offal frequently fed to dogs. Between 2017 and 2019, we conducted a multi-species serological survey in this protected area to assess HEV exposure in invasive mammals and in dog and human consumers of game meat. We also evaluated associations between seropositivity and environmental variables, as well as behavioral risk factors among game-meat consumers. Total anti-HEV antibodies were detected in 29/75 (38.67%) wild boar, 1/134 (0.75%) deer, 1/18 (5.6%) dogs, and 6/59 (10.17%) humans. A spatial cluster of seropositive wild boar was identified in a low-lying, flood-prone area near the confluence of the El Palmar stream and the Uruguay river, suggesting increased risk of environmental transmission. This is the first report of HEV exposure in wild boar from this park and in axis deer and dogs in Argentina. Participation in culling and game meat handling and consumption may contribute to HEV exposure pathways among humans. These findings improve understanding of HEV epidemiology at the wildlife–domestic animal–human interface and highlight the influence of environmental factors and human behavior on zoonotic virus circulation.