Dection of Hepatozoon parasites in wild rodents of Central Europe

GANZINELLI S; HAMÍKOVÁ Z; FOLDVARI G; SZEKERES S; SCHNITTGER L; KAZIMÍROVÁ M

Conferencia; 10th Tick and Tick-Borne Pathogens Conference; 2022

Canine hepatozoonosis caused by Hepatozoon canis is an emerging disease in Europe. Clinical signs are usually non-specific and vary from subclinical to life-threatening manifestations. Ticks, fleas and other arthropods, such as mites and lice, act as definitive hosts, and dogs become infected by ingesting these parasite-bearing ectoparasites. The present study was aimed at analyzing the Hepatozoon species found in wild rodents of Hungary and Slovakia, acting as potential parasite reservoirs. DNA was extracted from spleen and lung samples of rodents and infesting parasites and a region of the18S rRNA gene was PCR-amplified and sequenced. Two closely related genetic variants, named Hepatozoon sp. BV1 (AY600626) and Hepatozoon sp. BV2 (AY600625) were detected in Myodes glareolus (bank vole). Furthermore, Hepatozoon sp. BV1 was also detected in the flea species Ctenophthalmus agyrtes and Megabothris turbidus, collected from these rodents.Phylogenetic analysis demonstrated that 18S rRNA variants BV1 and BV2 correspond to previously described genotypes UR1 and UR2 of H. erhardovae, respectively. In addition, a different 18S rRNA sequence was identified in lung and spleen samples of the rodent Apodemus flavicollis (yellow-necked mouse), which showed an identity of only 99.32% with a sequence of Hepatozoon sp. (KX4536361) from an Arabian snake. This finding strongly suggested that it is a new, hitherto unknown isolate, here designated SF1. Phylogenetic analysis confirmed this assumption, since the SF1 sequence fell into an independent, strongly supported branch, found to be associated with Hepatozoon speciesinfecting rodents. In summary, analysis of 18S rRNA sequences derived from fleas and rodents and their comparison with the GenBank database revealed the presence of the two genetic variants, Hepatozoon sp. BV1 and BV2, which coexist and which were previously detected in isolates from Spain, Slovakia, Hungary and Poland. The BV1 variant was also detected in fleas parasitizing the sampled rodents, indicating that they represent the definitive host. Finally, in the rodent A. flavicollis, a putative novel species has been detected as evidenced by molecular phylogenetic analysis. H. canis was not detected in this study suggesting that wild rodents are not reservoirs for this parasite (Financed by the INTA project I103 and I109).