Tick-borne pathogens in ticks collected from dogs, Latvia, 2011–2016

Abstract

BackgroundDifferent tick species are able to transmit different pathogens, and tick-borne diseases are of substantial concern worldwide for both humans and animals. Environmental changes and changes in the range of tick species, including Dermacentor reticulatus in Europe, can affect the spread of zoonotic pathogens. The aim of this study was to investigate the prevalence of the tick-borne pathogens in ticks removed from dogs in Latvia, and to explore possible changes between years 2011 and 2016.ResultsIn 2011, only Ixodes ticks (221 Ixodes ricinus and 22 Ixodes persulcatus) were collected from dogs, while in 2016 tick samples belonged to Ixodes ricinus (360), Ixodes persulcatus (2) and Dermacentor reticulatus (27) species. In total, 35.8 and 40.0% of adult ticks were pathogen-positive in 2011 and 2016, respectively; the difference was not statistically significant (P > 0.05). The molecular analysis indicated the presence of 13 tick-borne microorganisms; the most prevalent pathogen was Rickettsia, followed by Borrelia burgdorferi sensu lato group spirochetes, Anaplasma phagocytophilum and Babesia species. Borrelia miyamotoi was also present. A co-infection with two and three tick-borne pathogens was detected in 7.9 and 7.4% of Ixodes ricinus and Dermacentor reticulatus, respectively. The results of this study confirmed that the spread of novel vectors could bring additional risk of exposure to novel emerging pathogens to pets and their owners, as both Babesia canis and Rickettsia raoultii were shown to be highly associated with Dermacentor reticulatus ticks in Latvia.ConclusionsThis study demonstrates the potential danger from the inadvertent introduction of novel disease pathogens and vectors. Awareness of co-infections and Dermacentor reticulatus-related pathogens needs to be increased.

Large-scale countrywide screening for tick-borne pathogens in field-collected ticks in Latvia during 2017–2019

“…The presence of Ba. canis in I. ricinus observed here is in accordance with a study conducted by Cieniuch et al [ 48 ] in Poland, which showed that approximately 1% of field-collected I. ricinus ticks were infected, and also agrees with our recent study on ticks collected from dogs [ 10 ]. Interestingly, in the present study, the prevalence of Ba.…”

“…Moreover, D. reticulatus has been detected in geographically separate new localities in the Riga region, indicating the development of new foci outside of the major distribution area. Similar to these findings, we reported in a recent study that from 2011 to 2016, D. reticulatus ticks were removed from dogs in western, southern and central parts of Latvia and the Riga region [ 10 ]. Outside of Latvia, the spread of D. reticulatus during the last decade has been notable in other European countries such as neighboring Lithuania [ 9 , 11 , 19 ].…”

“…All samples were tested for the presence of Babesia spp., Borrelia spp., A. phagocytophilum and Rickettsia spp. using a nested polymerase chain reaction (PCR) targeting the 18S rRNA, 16S rRNA and gltA genes, respectively, as previously described [ 10 ]. The presence of TBEV RNA in the samples was detected by reverse transcription real-time polymerase chain reaction (RT-qPCR) amplifying a fragment of the 3’ NCR (non-coding region) as previously described [ 14 ].…”

“…In Latvia, a Baltic state in northern Europe, three tick-borne diseases are registered annually: Lyme disease (borreliosis, 481 cases in 2018, 24.9 cases per 100,000 individuals), tick-borne encephalitis (TBE; 169 cases in 2018, 8.7 cases per 100,000 individuals), and granulocytic ehrlichiosis, or anaplasmosis (27 cases in 2018, 1.4 cases per 100,000 individuals) (data from the Centre for Disease Prevention and Control of Latvia; https://spkc.gov.lv/ ). Babesiosis is not registered in Latvia as a human disease; however, it is playing an increasingly important role in veterinary medicine [ 10 ]. During the last decade, in addition to the commonly recorded I. ricinus and I. persulcatus ticks, the appearance and spread of D. reticulatus populations was reported in Latvia [ 11 ].…”

Molecular Detection of Borrelia burgdorferi Sensu Lato and Anaplasma phagocytophilum in Ticks Collected from Dogs in Urban Areas of North-Eastern Poland

“…In our study, only 5 out of 402 (1.2%) engorged I. ricinus females showed the presence of A. phagocytophilum DNA. The prevalence of A. phagocytophilum was 6% in the DNA of adult I. ricinus ticks collected from dogs in Latvia, whereas in I. persulcatus and D. reticulatus, the pathogen was not identified [56]. Even though similar studies are scarce, our data did seem rather low for the country.…”