Sessions

The South American nutria (Myocastor coypus), an invasive rodent, has established stable populations in Hungary’s wetlands over the past decade. In addition to causing ecological and agricultural damage, it also poses a risk to human and animal health because it can serve as a potential reservoir for numerous pathogens. The wet, lush riparian areas with dense undergrowth that it favors also provide ideal conditions for the development and survival of ticks.

During the study, we examined 52 nutrias (n=52) trapped for pest control purposes in 17 locations in western Hungary. We searched the animals’ fur for ticks and, during necropsy, collected samples from various organs (diaphragm, liver, lungs, spleen, heart, and blood), resulting in a total of 209 samples. I then extracted DNA from these samples, which we subjected to PCR testing using primers specific for Piroplasma, Anaplasmataceae, Borrelia, Hepatozoon, and Rickettsia species; the positive samples were subsequently sequenced.

No ticks were found on the fur of the trapped animals at the time of examination. Molecular testing revealed that 8 samples were positive for Babesia microti, originating from a total of 6 animals, resulting in an individual-level prevalence of 11.5%. Screening for the Anaplasmataceae family yielded 9 positive samples; among these, we detected the presence of Candidatus Neoehrlichia species in the sequenced products from 5 samples derived from 3 animals (5,8% prevalence). All samples tested negative for Borrelia and Hepatozoon pathogens, and sequencing of the single positive product obtained during Rickettsia-specific PCR did not confirm the presence of the pathogen.

Our results confirm that expanding nutria populations may play a role in the maintenance of tick-borne zoonotic pathogens. Epidemiological monitoring of this species is a task of paramount importance.