# Ancylostomatidae in wild canids and felids from Romania: new host associations and haplotype diversity

## TL;DR

This study identifies hookworms in wild carnivores in Romania, revealing new host associations and genetic diversity, which could impact domestic animals and humans.

## Contribution

The study reports new host-parasite associations and provides the first comprehensive molecular assessment of hookworm diversity in European wild carnivores.

## Key findings

- Hookworms were detected in 14.1% of wild carnivores, with three species identified.
- The Eurasian lynx was found to host Ancylostoma caninum for the first time.
- Molecular analysis revealed 14 unique hookworm haplotypes with global genetic similarities.

## Abstract

Hookworms (Ancylostomatidae) significantly impact on the health of both domestic animals and humans worldwide, with some species capable of causing zoonotic diseases. While hookworm infections in pets are frequently reported in Europe primarily through coproscopic studies, there are limited data regarding their presence in wild carnivores. To address this, this study aimed to assess the diversity, prevalence, and distribution of hookworms in wild canids and felids from Romania through both morphological and molecular analyses.

From November 2011 to February 2025, 319 carcasses belonging to six species of wild canids and felids from Romania [23 gray wolves (Canis lupus), 137 golden jackals (Canis aureus), 79 red foxes (Vulpes vulpes), 2 raccoon dogs (Nyctereutes procyonoides), 70 European wildcats (Felis silvestris), and 8 Eurasian lynxes (Lynx lynx)] were collected as road kills or legally hunted. Hookworms were recovered from the intestinal tract during necropsy and preserved in formalin for morphological examination and in absolute ethanol for genetic analysis. Genomic DNA was extracted and analyzed using a PCR targeting a barcode region of the second nuclear ribosomal internal transcribed spacer (ITS-2), followed by sequencing. Sequencing results were compared with other entries from GenBank™.

The overall hookworm infection rate was 14.1%, with hookworms detected in 4 wolves (17.4%), 23 golden jackals (16.8%), 11 European wildcats (15.7%), 4 red foxes (5.1%), 2 raccoon dogs (100%), and 1 lynx (12.5%). Three hookworm species were identified: Uncinaria stenocephala, Ancylostoma caninum, and A. tubaeforme. Molecular analysis revealed 14 unique sequences, comprising nine haplotypes of U. stenocephala, three of A. caninum, and two of A. tubaeforme. We report for the first time the Eurasian lynx as a host for A. caninum, expanding the known host range of this species.

This study provides the first comprehensive molecular assessment of hookworm diversity in European wild carnivores, showing new host–parasite associations and highlighting the importance of these hosts as reservoirs for domestic pets and, potentially, humans. The detected haplotypes showed high similarity to isolates from Europe, Asia, and the Americas, indicating a broad global connectivity of hookworm populations.

The online version contains supplementary material available at 10.1186/s13071-025-07219-7.