# Candidatus Neoehrlichia sp. in an Austrian fox is distinct from Candidatus Neoehrlichia mikurensis, but closer related to Candidatus Neoehrlichia lotoris

## TL;DR

A new type of Candidatus Neoehrlichia was found in an Austrian fox, distinct from known species and more similar to one found in raccoons in the USA.

## Contribution

First global detection of a Candidatus Neoehrlichia sp. in a red fox, distinct from C. mikurensis and closer to C. lotoris.

## Key findings

- Candidatus Neoehrlichia sp. was detected in a red fox in Vorarlberg, Austria.
- The strain is genetically closer to C. lotoris than to C. mikurensis.
- This is the first worldwide report of this species in a red fox.

## Abstract

Candidatus Neoehrlichia came under the focus of recent research in terms of human and pet relevance. Candidatus Neoehrlichia mikurensis seems to be relatively abundant in animals and humans from Central European countries, whereas Candidatus Neoehrlichia lotoris was found solely in raccoons from the USA.

Spleen samples from a total of 164 red foxes, originating from two western provinces in Austria (Tyrol and Vorarlberg), were collected and examined for the presence of tick-borne bacteria of the family Anaplasmataceae by PCR and sequencing. In a fox sample originating from Vorarlberg Candidatus Neoehrlichia sp. was found, which is genetically (16S rRNA, groEL) closely related to Candidatus Neoehrlichia lotoris but clearly distinct from Candidatus Neoehrlichia mikurensis.

The present study revealed, for the first time, the occurrence of Candidatus Neoehrlichia sp. in a red fox worldwide. A continuing screening of wild carnivores, especially foxes, and ticks for this potential pathogen is required to evaluate the actual occurrence and distribution of these bacteria. Further research is needed to elucidate the relationships of Neoehrlichia, as well as their reservoir and impact on wildlife, pets and humans.