Search results for "ixodes ricinus"
showing 10 items of 30 documents
Predicting and mapping human risk of exposure to ixodes ricinus nymphs using climatic and environmental data, Denmark, Norway and Sweden, 2016
2019
Background Tick-borne diseases have become increasingly common in recent decades and present a health problem in many parts of Europe. Control and prevention of these diseases require a better understanding of vector distribution. Aim Our aim was to create a model able to predict the distribution of Ixodes ricinus nymphs in southern Scandinavia and to assess how this relates to risk of human exposure. Methods We measured the presence of I. ricinus tick nymphs at 159 stratified random lowland forest and meadow sites in Denmark, Norway and Sweden by dragging 400 m transects from August to September 2016, representing a total distance of 63.6 km. Using climate and remote sensing environmental…
Competition between strains of Borrelia afzelii inside the rodent host and the tick vector
2018
Multiple-strain pathogens often establish mixed infections inside the host that result in competition between strains. In vector-borne pathogens, the competitive ability of strains must be measured in both the vertebrate host and the arthropod vector to understand the outcome of competition. Such studies could reveal the existence of trade-offs in competitive ability between different host types. We used the tick-borne bacteriumBorrelia afzeliito test for competition between strains in the rodent host and the tick vector, and to test for a trade-off in competitive ability between these two host types. Mice were infected via tick bite with either one or two strains, and these mice were subse…
Predicting the spatial abundance of Ixodes ricinus ticks in southern Scandinavia using environmental and climatic data
2019
AbstractRecently, focus on tick-borne diseases has increased as ticks and their pathogens have become widespread and represent a health problem in Europe. Understanding the epidemiology of tick-borne infections requires the ability to predict and map tick abundance. We measured Ixodes ricinus abundance at 159 sites in southern Scandinavia from August-September, 2016. We used field data and environmental variables to develop predictive abundance models using machine learning algorithms, and also tested these models on 2017 data. Larva and nymph abundance models had relatively high predictive power (normalized RMSE from 0.65–0.69, R2 from 0.52–0.58) whereas adult tick models performed poorly …
Temporal dynamics of the tick Ixodes ricinus in northern Europe : epidemiological implications
2017
Background Tick-borne pathogens pose an increasing threat to human and veterinary health across the northern hemisphere. While the seasonal activity of ticks is largely determined by climatic conditions, host-population dynamics are also likely to affect tick abundance. Consequently, abundance fluctuations of rodents in northern Europe are expected to be translated into tick dynamics, and can hence potentially affect the circulation of tick-borne pathogens. We quantified and explained the temporal dynamics of the tick Ixodes ricinus in the northernmost part of its European geographical range, by estimating (i) abundance in vegetation and (ii) infestation load in the most common rodent speci…
Sympatric Ixodes-tick species: pattern of distribution and pathogen transmission within wild rodent populations
2018
AbstractThe generalist tick Ixodes ricinus is the most important vector for tick-borne pathogens (TBP), including Borrelia burgdorferi sensu lato, in Europe. However, the involvement of other sympatric Ixodes ticks, such as the specialist vole tick I. trianguliceps, in the enzootic circulations of TBP remains unclear. We studied the distribution of I. ricinus and I. trianguliceps in Central Finland and estimated the TBP infection likelihood in the most common rodent host in relation with the abundance of the two tick species. Ixodes trianguliceps was encountered in all 16 study sites whereas I. ricinus was frequently observed only at a quarter of the study sites. The abundance of I. ricinus…
Monitoring of ticks and tick-borne pathogens through a nationwide research station network in Finland.
2020
In 2015 a long-term, nationwide tick and tick-borne pathogen (TBP) monitoring project was started by the Finnish Tick Project and the Finnish Research Station network (RESTAT), with the goal of producing temporally and geographically extensive data regarding exophilic ticks in Finland. In the current study, we present results from the first four years of this collaboration. Ticks were collected by cloth dragging from 11 research stations across Finland in May September 2015-2018 (2012-2018 in Seili). Collected ticks were screened for twelve different pathogens by qPCR: Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, Borrelia burgdorferi sensu stricto, Borrelia miyamotoi, Babesia sp…
Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
AbstractBackgroundTicks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur:IxodesricinusandIxodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change.MethodsWe used species distribution modelling techniques to predict the distributions ofI.ricinusandI.persulcatus,using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Fin…
Diversity of ankA and msp4 genes of Anaplasma phagocytophilum in Slovenia.
2015
Granulocytic anaplasmosis is a tick transmitted emerging disease in Europe and worldwide. The agent, Anaplasma phagocytophilum is transmitted by ticks of the genus Ixodes and causes infections in humans and domestic animals. The analysis of different target genes showed that in nature several genetic variants of A. phagocytophilum were present. The purpose of our study was to genetically characterize A. phagocytophilum strains from eight humans, 16 dogs, 12 wild boars, one bear and 18 tick pools from Slovenia. Therefore, the ankA and msp4 genes of A. phagocytophilum were chosen. The same genetic ankA and msp4 variant of A. phagocytophilum was detected in humans, wild boar and a part of the …
Tick-borne pathogens in Ixodes ricinus ticks collected from migratory birds in southern Norway
2020
Birds are important hosts for the first life stages of the Ixodes ricinus tick and they can transport their parasites over long distances. The aim of this study was to investigate the prevalence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Neoehrlichia mikurensis and Rickettsia helvetica in ticks collected from migratory birds in Norway. A total of 815 Ixodes ricinus ticks from 216 birds trapped at Lista Bird Observatory in southern Norway during spring and autumn migration in 2008 were analysed by real-time PCR. B. burgdorferi s. l. was the most prevalent pathogen, detected in 6.1% of the ticks. The prevalence of N. mikurensis, A. phagocytophilum and R. helvetica was 1.2%…
Heterogeneity of host-parasite relationships : ecological and evolution significance
2005
Although parasites have been studied for a long time, the major knowledge concern parasite which have medical or veterinary interest. Whereas they are omnipresent in the nature, the role of parasite infections on natural populations is poorly understood. One of the aim of this work was to study the pathogenicity of two groups of parasites (ticks and Haemosporidae) among natural populations of blackbirds. The study revealed that both parasites are associated with body condition and immune response. However, the study of an urban blackbird population did not confirm the effect of Haemosporidae on the survey and on the population dynamic.The impact of spatial pattern on the relation between ho…