A Survey of Hepatitis B Virus and Hepatitis E Virus at the Human-Wildlife Interface in the Peruvian Amazon.

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.

Toxoplasma gondii in a Remote Subsistence Hunting-Based Indigenous Community of the Peruvian Amazon.

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.

Variación ontogénica y sexual de Oecomys bicolor (Rodentia, Cricetidae) de Perú y Ecuador / Ontogenetic and sexual variation of Oecomys bicolor (Rodentia, Cricetidae) from Peru and Ecuador

Oecomys es un género rico en diversidad de especies de tamaño pequeño a mediano. Dentro del género, la especie O. bicolor es reconocida morfológicamente con relativa facilidad; sin embargo, se ha reportado en distintas poblaciones de la especie variaciones individuales, con respecto al tamaño y color, por lo que podría tratarse de un complejo de especies. La información intraespecífica es muy poca a pesar de su amplia distribución; no obstante, esta información es necesaria para la delimitación de la especie, así como explicar variaciones en poblaciones. Por ello, en el presente estudio se analizaron 148 especímenes de O. bicolor, con el objetivo de evaluar la variación no geográfica referida al sexo y edad. Se analizaron 13 variables cráneo-dentales. Mediante aproximaciones estadísticas univariadas y multivariadas se demostró que el dimorfismo sexual no es significativo; por otro lado, la variación ontogénica es considerable entre jóvenes y adultos, estos resultados son consistentes con estudios previos realizados en roedores sigmodontinos, Se recomienda continuar los estudios de variación geográfica tomando en cuenta las edades 3, 4 y 5, y agrupando machos y hembras

Oecomys is a moderately specious genus of small to medium size. Within the genus, the species O. bicolor is readily recognized; however, it has been reported individual variation in size and color from different populations suggesting that the species could be a species complex. Intraspecific information in O. bicolor is limited despite its wide distribution; but, this information is necessary for delimiting the species as well as explaining variations within populations. Therefore, in the present study 148 specimens of O. bicolor were analyzed, with the objective of evaluating the non-geographic variation of the species related to sex and age. 13 skull-dental variables were analyzed. Univariate and multivariate statistical approximations showed that sexual dimorphism is not significant; on the other hand, the ontogenic variation is considerable among young adults, these results are consistent with previous studies in sigmodontine rodents. It is recommended to continue studies of geographic variation with only ages 3, 4 and 5, and treating males and females collectively