Anaplasmataceae closely related to Ehrlichia chaffeensis and Neorickettsia helminthoeca from birds in Central Europe, Hungary

Abstract

Increasing amount of data attest that (in the context of vector-borne infections) birds are not only important as hosts of blood-sucking arthropod vectors, but also as reservoirs of vector-borne pathogens. From 2015 to 2019 cadavers of 100 birds (from 45 species, nine orders) were collected in Hungary, and their organs were screened for DNA from a broad range of vector-borne bacteria with PCR and sequencing. Molecular analyses revealed the presence of Anaplasmataceae, and sequencing identified bacteria closely related to Neorickettsia helminthoeca and Ehrlichia chaffeensis in a Eurasian teal (Anas crecca) and a song thrush (Turdus philomelos), respectively. All samples were PCR negative for rickettsiae, borreliae, Francisella and Coxiella spp., as well as for piroplasms. To our knowledge, this is the first report of a Neorickettsia and an Ehrlichia sp., which belong to the phylogenetic groups of N. helminthoeca and E. chaffeensis, respectively, from Europe. The potential presence of these two vector-borne bacteria needs to be taken into account during future studies on the eco-epidemiology of Anaplasmataceae in Europe.

Keywords: Borrelia; Coxiella; Francisella; Piroplasm; Rickettsia; Tick-borne; Vector-borne.

Fig. 1

Minimum Evolution phylogenetic tree of Anaplasmataceae (with Rickettsia parkeri as outgroup) based on the 16S rRNA gene. There were a total of 1227 positions in the final dataset. Genotypes from this study are highlighted with red color and bold accession numbers. For each item, the isolation source and country of origin are shown in parentheses between the species name and relevant GenBank accession number. The scale-bar indicates the number of substitutions per site