High prevalence of Ancylostoma caninum infection in black-eared opossums (Didelphis aurita) in an urban environment.

Marsupials of the genus Didelphis, such as black-eared opossums (Didelphis aurita), are common synanthropic animals in urban areas of Brazil. These marsupials are frequently parasitized by numerous helminth species, including ancylostomatid nematodes. This study aimed to report the occurrence of Ancylostoma caninum in black-eared opossums captured in an urban environment of Southeastern Brazil and discuss the potential impact of these findings for public health. From January to June 2019, we collected fecal samples from 49 restrained opossums and evaluated by a simple flotation method; Helminth eggs were observed at different magnifications and identified according to morphological and morphometric features. Genomic DNA was extracted from Ancylostomatidae eggs and screened by duplex PCR for Ancylostoma spp. and Necator americanus using primers that amplify a region of internal transcribed spacer 2 and the 28S ribosomal RNA (ITS2-28S rRNA). Ancylostoma spp. eggs were detected in 65.3% (32/49) of the animals. Sequence analysis revealed 100% homology with A. caninum sequences from GenBank. Our results demonstrate a new host-parasite interaction for A. caninum, suggesting that black-eared opossums may participate in the zoonotic cycle of this parasite in urban areas of Brazil.