Zoonotic parasitic species identified in foxes

Abstract

Introduction. The red fox (Vulpes vulpes, Linnaeus, 1758) is the most widespread wild carnivore, exhibiting a pronounced ability to adapt to human-modified environments (synanthropization). It is distributed across all continents except Antarctica. This species plays a critical role in regulating rodent population dynamics, with rodents serving as potential definitive, intermediate, or paratenic hosts for a wide variety of parasitic species, many of which carry significant zoonotic and epizootic risks. The red fox itself functions as a natural reservoir, facilitating the transmission of parasitic zoonoses from wildlife to domestic animals. In the Republic of Moldova, the red fox population has undergone a 7- to 8-fold increase in density, a trend that may elevate the risk of human infection with vectorborne zoonotic pathogens. Purpose of the study. This study aimed to conduct an ecoparasitological assessment of the parasitic fauna epidemiological characteristics in V. vulpes and identify the zoonotic parasite groups. Material and methods. Parasitological examinations were conducted on biological samples collected from red foxes across various habitats of the Republic of Moldova, including both natural and anthropogenically influenced biotopes. A total of 69 fecal samples were collected and analysed in the Laboratory of Parasitology and Helminthology at the Institute of Zoology. The diagnostic procedures followed standardized coprological techniques, including the methods of Popova, Baermann, Fülleborn, and Darling, as well as the sedimentation technique. Results. The taxonomic structure of the parasitic fauna includes 5 classes, 10 families, 11 genera, and 12 species. Analysing the parasitic species from an epidemiological perspective, it was found that 10 species (83.3%) with wide distribution, have zoonotic significance (Alaria alata, Mesocestoides lineatus, Taenia spp., Syphacia obvelata, Strongyloides stercoralis, Toxocara canis, Toxascaris leonina, Ancylostoma caninum, Capillaria hepatica, Trichuris vulpis), posing a major risk to public health. Only 2 species are characteristic of canids (Isospora canis, Trichuris muris), and all identified infestations (100%) can also parasitize domestic animals, including game fauna. The zoonotic classification comprises 2 species of direct zoonotic parasites (T. leonina, T. canis), 5 species of saprozoonotic parasites (I. canis – 14.3%, A. caninum – 8.7%, S. obvelata – 17.0%, S. stercoralis – 13.3%, T. vulpis – 26.1%, T. muris – 4.4%), 1 species of metazoonotic parasites (A. alata – 51.0%), and several species of cyclozoonotic parasites (Taenidae – 27.0%, M. lineatus – 21.7%, A. caninum – 8.7%, C. hepatica – 35.0%). All investigated samples (100%) were infected with parasitic stages. Conclusions. The red fox occupies extensive, overlapping territories (15–20 km) that encompass both natural and anthropized landscapes. Its broad diet facilitates the transmission and maintenance of parasitic stages among a variety of wild and domestic hosts. Consequently, the red fox is a key reservoir for zoonotic parasites, particularly in transitional zones where contact with livestock and companion animals is common.