Toxoplasma gondii is a ubiquitous zoonotic protozoan parasite that infects a wide variety range of warm-blooded animals. This study describes the epidemiological scenario of T. gondii in an indigenous community that relies on subsistence hunting in a well-conserved and isolated area of the Peruvian Amazon. The high seropositivity against T. gondii in humans (83.3% IgG and 6.1% IgM), wild mammals (30.45%, 17 species), peri-domestic rodents (10.0% Rattus sp.), and domestic animals (94.1% dogs and 100% cats) indicates the existence of a sylvatic cycle in the community under study. Individual age was found to be positively associated with IgG detection against T. gondii but not with IgM. It is estimated that each family consumed 5.67 infected animals per year with terrestrial species having higher infective rates than arboreal species. The main risk factors included improper handling and cooking of wild meat, poor hygiene practices, and feeding uncooked offal to domestic animals. This scenario results in a continuous process of infection and reinfection within the indigenous community with cats, dogs, and peri-domestic animals becoming infected through the ingestion of infected raw viscera. Our results emphasize the need to promote safe food handling practices and disposal of waste materials from hunted animals in such communities.

Hepatitis B virus (HBV) and Hepatitis E virus (HEV) are zoonotic pathogens posing significant health concerns in rural Amazonia, a region marked by high endemicity, poverty, and limited healthcare access. However, the epidemiology of HBV and HEV in this ecosystem remains underexplored. This study examines the circulation of HBV and HEV at the human–wildlife interface and identifies risk factors within an isolated Amazonian indigenous community reliant on hunting for subsistence. Antibodies against HBV core antigens (HBcAbs) were found in three wildlife species: Cuniculus paca (0.8%), Tayassu pecari (1.6%), and Mazama americana (4.1%), marking the first record of HBV antibodies in free-ranging wildlife in the Amazon. However, further research is necessary to identify circulating strains and their relation to human HBV. HBcAbs were also detected in 9.1% of human samples, confirming exposure to HBV in the region. HEV IgG antibodies were present in 17.1% of humans and were associated with higher age. All wildlife and domestic animal samples tested negative for HEV, but transmission through consumption of wild animals and contaminated water needs further investigation. The identified risk factors highlight the urgent need for measures to promote safer food handling, improved sanitation, hygiene, and practices related to contact with wild animals.

Trichinellosis is a global parasitic food-borne disease affecting humans, domestic and wild animals. Beyond its health implications, trichinellosis also has negative economic impacts for the pork industry. However, to date, few studies have analyzed Trichinella infections in the Amazon region. This study aimed to increase the information on the circulation of Trichinella spp. in free-ranging peccaries in two areas in the Northern Peruvian Amazon. Between 2008 and 2020, local subsistence hunters collected dried blood spots on filter paper from 140 free-ranging Pecari tajacu and 93 Tayassu pecari (n= 233 total), to test for antibodies against Trichinella spp. All animals were negative in serological tests for anti-Trichinella spp. antibodies. No evidence of nematodes was also found in the histological sections of the analyzed peccary diaphragm samples (n=29). In the two study areas, free-ranging peccary populations do not show evidence of having been exposed to the parasite. This is the first survey of Trichinella spp. in wild peccaries conducted in the Amazon. Negative result studies offer key insights into trichinellosis distribution.

Neotropical echinococcosis (NE) is a neglected zoonotic disease in tropical Latin America caused by Echinococcus vogeli. This study analyzed behavioral factors influencing NE transmission across 52 settlements, including rural and urban sites (285 respondents) within its distribution range. Of the surveyed communities, cysts in pacas associated with E. vogeli were reported in 86.5 % of Amazonian rural communities, 75.0 % of Amazonian cities, and 75.0 % of non-Amazonian rural areas. However, only 43.7 % of respondents in Amazonian rural communities and 23.1 % in non-Amazonian rural communities perceived these lesions as dangerous. Discarded livers were often fed to dogs, particularly in Amazonian rural (62.0 %) and non-Amazonian rural (43.6 %) communities, perpetuating the parasite's cycle. Routine dog deworming was also infrequent in rural areas (13.1 % in Amazonian rural and 38.5 % in non-Amazonian rural communities) in comparison to Amazonian cities (72.7 %). Additionally, limited access to healthcare in rural regions likely delays diagnoses, worsening disease outcomes. Human activities, such as handling wild meat and feeding infected organs to dogs, are key to disease transmission. High-risk practices for E. vogeli transmission are significantly more frequent in rural communities. Preventive strategies should focus on wildlife handling and domestic animal sanitation to reduce NE and other zoonotic diseases related to the wild meat chain, especially in rural areas.