Diverse tick-borne microorganisms identified in free-living ungulates in Slovakia

Background: Free-living ungulates are hosts of ixodid ticks and reservoirs of tick-borne microorganisms in central Europe and many regions around the world. Tissue samples and engorged ticks were obtained from roe deer, red deer, fallow deer, mouflon, and wild boar hunted in deciduous forests of south-western Slovakia. DNA isolated from these samples was screened for the presence of tick-borne microorganisms by PCR-based methods. Results: Ticks were found to infest all examined ungulate species. The principal infesting tick was Ixodes ricinus, identified on 90.4% of wildlife, and included all developmental stages. Larvae and nymphs of Haemaphysalis concinna were feeding on 9.6% of wildlife. Two specimens of Dermacentor reticulatus were also identified. Ungulates were positive for A. phagocytophilum and Theileria spp. Anaplasma phagocytophilum was found to infect 96.1% of cervids, 88.9% of mouflon, and 28.2% of wild boar, whereas Theileria spp. was detected only in cervids (94.6%). Importantly, a high rate of cervids (89%) showed mixed infections with both these microorganisms. In addition to A. phagocytophilum and Theileria spp., Rickettsia helvetica, R. monacensis, unidentified Rickettsia sp., Coxiella burnetii, "Candidatus Neoehrlichia mikurensis", Borrelia burgdorferi (s.l.) and Babesia venatorum were identified in engorged I. ricinus. Furthermore, A. phagocytophilum, Babesia spp. and Theileria spp. were detected in engorged H. concinna. Analysis of 16S rRNA and groEL gene sequences revealed the presence of five and two A. phagocytophilum variants, respectively, among which sequences identified in wild boar showed identity to the sequence of the causative agent of human granulocytic anaplasmosis (HGA). Phylogenetic analysis of Theileria 18S rRNA gene sequences amplified from cervids and engorged I. ricinus ticks segregated jointly with sequences of T. capreoli isolates into a moderately supported monophyletic clade. Conclusions: The findings indicate that free-living ungulates are reservoirs for A. phagocytophilum and Theileria spp. and engorged ixodid ticks attached to ungulates are good sentinels for the presence of agents of public and veterinary concern. Further analyses of the A. phagocytophilum genetic variants and Theileria species and their associations with vector ticks and free-living ungulates are required.Fil: Kazimírová, Mária. Slovak Academy of Sciences. Institute of Zoology; EslovaquiaFil: Hamšíková, Zuzana. Slovak Academy of Sciences. Institute of Zoology; EslovaquiaFil: Spitalská, Eva. Slovak Academy of Sciences. Institute of Virology. Biomedical Research Center,; EslovaquiaFil: Minichová, Lenka. Slovak Academy of Sciences. Institute of Virology. Biomedical Research Center,; EslovaquiaFil: Mahríková, Lenka. Slovak Academy of Sciences. Institute of Zoology; EslovaquiaFil: Caban, Radoslav. Široká ; EslovaquiaFil: Sprong, Hein. National Institute for Public Health and Environment.Laboratory for Zoonoses and Environmental Microbiology; Países BajosFil: Fonville, Manoj. National Institute for Public Health and Environment.Laboratory for Zoonoses and Environmental Microbiology; Países BajosFil: Schnittger, Leonhard. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kocianová, Elena. Slovak Academy of Sciences. Institute of Virology. Biomedical Research Center,; Eslovaqui

A review on the eco-epidemiology and clinical management of human granulocytic anaplasmosis and its agent in Europe

Anaplasma phagocytophilum is the agent of tick-borne fever, equine, canine and human granulocytic anaplasmosis. The common route of A. phagocytophilum transmission is through a tick bite, the main vector in Europe being Ixodes ricinus. Despite the apparently ubiquitous presence of the pathogen A. phagocytophilum in ticks and various wild and domestic animals from Europe, up to date published clinical cases of human granulocytic anaplasmosis (HGA) remain rare compared to the worldwide status. It is unclear if this reflects the epidemiological dynamics of the human infection in Europe or if the disease is underdiagnosed or underreported. Epidemiologic studies in Europe have suggested an increased occupational risk of infection for forestry workers, hunters, veterinarians, and farmers with a tick-bite history and living in endemic areas. Although the overall genetic diversity of A. phagocytophilum in Europe is higher than in the USA, the strains responsible for the human infections are related on both continents. However, the study of the genetic variability and assessment of the difference of pathogenicity and infectivity between strains to various hosts has been insufficiently explored to date. Most of the European HGA cases presented as a mild infection, common clinical signs being pyrexia, headache, myalgia and arthralgia. The diagnosis of HGA in the USA was recommended to be based on clinical signs and the patient’s history and later confirmed using specialized laboratory tests. However, in Europe since the majority of cases are presenting as mild infection, laboratory tests may be performed before the treatment in order to avoid antibiotic overuse. The drug of choice for HGA is doxycycline and because of potential for serious complication the treatment should be instituted on clinical suspicion alone

Ecology of Anaplasmosis in Central Europe

Anaplasma phagocytophilum is the causative agent of granulocytic anaplasmosis of both medical and veterinary importance. In Europe, it is transmitted by the Ixodid ticks, mostly Ixodes ricinus, however other tick species such as Ixodes trianguliceps probably contribute to the enzootic cycle of this bacterium. According to some studies, the intraspecific variability of A. phagocytophilum plays an important role in the ecology of this pathogen. In order to understand the ecology of this pathogen in Central Europe we have analyzed and compared the genetic variability of different A. phagocytophilum strains from questing and feeding ticks collected from vegetation and different vertebrate hosts (roe deers, rodents, birds, sheeps, dogs) as well as blood and biological samples of some vertberate hosts (rodents and birds) from two regions of Central Europe (Slovakia and Northern Italy). A. phagocytophilum was detected in questing and host feeding I. ricinus ticks from all studied sites, rodent feeding I. trianguliceps, ear and spleen biopsies of rodents. Prevalence of A. phagocytophilum in areas with rodents was much lower (1.1%, 0.6%) than in areas without rodents (6%). In areas where I. trianguliceps were absent we did not detect A. phagocytophilum in rodents. Phylogenetic analysis of four genetic loci in positive samples have shown that genotypes in questing I. ricinus and feeding I. ricinus from ungulates, birds and dogs were distinct from genotypes found in rodents and feeding I. trianguliceps. Msp4, DOV and GroESL sequences of A. phagocytophilum genotypes showed considerable heterogeneity but none of the positive questing I. ricinus tick was infected with the rodent genotype that was identical to the genotype found in I. trianguliceps. GroESL sequences from rodents were closely related to the sequences found in questing I. persulcatus. Our study from Central Europe confirms the previous findings from UK that A. phagocytophilum strains have specific associations with two vectors and different reservoir hosts. Unlike in the US, A. phagocytophilum ecotypes that are associated with rodents are probably transmitted solely by I.trianguliceps ticks, therefore these strains are not of risk for human

Prevalence and genetic variability of Anaplasma phagocytophilum in feeding I. ricinus from wildlife and domestic host species in Northern Italy

In Europe, Anaplasma phagocytophilum is an emerging tick-borne pathogen with both medical and veterinary importance, being the causative agent of human granulocytic anaplasmosis (HGA) and the tick-borne fever of domestic animals. Its ecology and its molecular diversity in Europe is currently under assessement. Therefore, we analyzed and compared the genetic variability of different A. phagocytophilum strains identified in feeding ticks collected from roe deer, rodents, birds, sheep’s, dogs from Trentino region of Northern Italy. Furthermore, prevalence of other pathogens of public health importance such as Babesia sp., Borrelia sp. and Rickettsia sp. was also estimated

Population genetic of the wood tick Ixodes ricinus (acari: Ixodidae): new insight into dispersal capacity in relation to host movements: bloodmeal analysis in questing ticks: application of High Resolution Melting (HRM)

Ixodes ricinus is a hematophagous arthropod considered as one of the main vector of human infectious diseases in Europe. Higher minimum temperatures and earlier spring permit the tick and so tick-borne disease to expand towards higher altitude and latitude. Little is know about the genetics of this vector. In this research we are focusing on a little geographical area (province of Trento, northern Italy) in which questing and feeding ticks will be collected and then analysed using the RAD-seq technology and the classical population genetics inference. A better knowledge of genetic features of tick populations and the analysis of the relation between vector and different host-species, exploited to obtain the blood-meal, will allow us to improve the understanding and the design of ecological models of vector-parasite-host interaction

Effect of climate and habitat type on the spatio-temporal variability of tick-borne bacteria in Europe

The incidence of tick-borne diseases caused by Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Rickettsia spp. has been rising in Europe in recent decades. Early pre-assessment of acarological hazard still represents a complex challenge. The aim of this study was to model Ixodes ricinus questing nymph density and its infection rate with B. burgdorferi s.l., A. phagocytophilum and Rickettsia spp. in five European countries (Italy, Germany, Czech Republic, Slovakia, Hungary) in various habitat types differing in use and anthropisation (agricultural, urban and natural) with climatic and environmental factors (Normalized Difference Vegetation Index, Normalized Difference Water Index, Land Surface Temperature and precipitation). We show that the relative abundance of questing nymphs was significantly associated with climatic conditions, such as higher values of NDVI recorded in the sampling period, while no differences were observed among habitat types. However, the density of infected nymphs (DIN) also depended on the pathogen considered and habitat type. These results contribute to a better understanding of the variation in acarological hazard for Ixodes ricinus transmitted pathogens in Central Europe and provide the basis for more focused ecological studies aimed at assessing the effect of land use in different habitat types on tick-host pathogens interaction