Brown dog ticks collected in Romania and Hungary: molecular identification and pathogens

• Autoři: GHODRATI Sajjad
• Rok publikování: 2024
• Druh: Konferenční abstrakty
• Popis: Introduction Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) refers to a group of tick species commonly called brown dog ticks. Ticks in the R. sanguineus complex are three-host parasites typically found on dogs, occasionally infesting humans and a variety of wild and domestic animals, such as rodents and birds. Some of the brown dog ticks are considered invasive species with extending distribution, mainly due to their association with domestic dogs. These ticks are mostly found in tropical and subtropical areas and their fast-extending distribution range is apparently enhanced also by climatic and environmental changes. Rhipicephalus sanguineus s.l. are well-known vectors of a range of pathogens of medical and veterinary importance. These include Anaplasma, Ehrlichia, Rickettsia, and piroplasmids such as Babesia, Theileria, and Hepatozoon. The differences in vectorial capacity of different taxa within the R. sanguineus s.l. represent a neglected part in the ecology of this group of tick-borne pathogens because many previous studies do not distinguish properly between the species of these ticks. Moreover, the asymptomatic status of infected dogs from endemic foci further increases the chance of pathogen importation into non-endemic regions with traveling dogs. The taxonomy of R. sanguineus s.l. ticks has been questioned and debated for many years. Several factors contribute to this confusion, including the limited description of the original species and the high level of morphological similarity among ticks within the complex. For instance, R. rossicus looks very similar to R. pumilio, and R. linnaei resembles R. sanguineus sensu stricto, as do R. hibericus and R. turanicus. Accurate identification of R. sanguineus s.l. species is crucial for understanding their role as disease vectors. Despite recent research on the genetic diversity of these ticks and newly described taxa, there are still gaps in our understanding of the epidemiology, vector capacity, and vector competence. Only in the last three years, three new species have been distinguished, raising questions about their roles in disease transmission. For example, R. linnaei (2022) was previously known as the "tropical lineage" of Rhipicephalus sanguineus, distinct from the "temperate lineage" now referred to as R. sanguineus s.str. Similarly, R. rutilus (2023) was formerly referred to as the Southeastern Europe lineage of R. sanguineus, and R. hibericus (2024) was previously identified as R. turanicus in Southwestern Europe. Descriptions and re-descriptions of new species over the last decade suggest that many ticks “superficially” identified as R. sanguineus may actually be other species, calling for more intense research. In Europe, this includes not only the “core” distribution range in the Mediterranean but also countries where Rhipicephalus ticks range from sporadic to endemic, including Hungary and Romania. In Hungary, canine pathogens such as A. platys, B. vogeli, and R. conorii have never been reported. Similarly, the ability of R. rossicus, the common dog tick in Eastern Romania, to transmit pathogens is unclear and likely underestimated. The genetic complexity of the brown dog tick led us to conduct genetic identification of brown dog ticks collected from domestic dogs and vegetation in Hungary and Romania. We also investigated the presence of pathogens Ehrlichia, Anaplasma, Rickettsia, and piroplasmids, including Babesia, Theileria, and Hepatozoon.