Tick Dermacentor Marginatus Research Articles

DETECTION OF CHLAMYDIA-LIKE MICROORGANISM WADDLIA CHONDROPHILA IN TICKS

Chlamydia-like microorganism Waddlia chondrophila (C. Chondrophila) is a new pathogen that causes miscarriages and abortions in humans and cattle. This bacterium is considered as a potential zoonotic agent. The main reservoirs and carriers of C. chondrophila are ixodic ticks, and determining their role remains the most difficult and interesting question to be solved in future studies.The purpose of this study was to identify chlamydia in ixodic ticks collected from cattle by molecular methods. Polymerase chain reaction (PCR) and sequencing were used to confirm the presence of the pathogen in tick samples collected from domestic animals.The analysis of nucleotide sequences showed that the DNA of the bacterium W. chondrophila was detected in the ticks Dermacentor marginatus, Hyalomma asiaticum, Hyalomma marginatum, Ixodes persulcatus, Hyalomma anatolicum. Among 156 tick samples collected from North Kazakhstan, West Kazakhstan, Zhambyl and Turkestan regions, 7% were positive for chlamydia-like microorganism W. chondrophila.The presence of DNA of the chlamydia-like W. chondrophila microorganism in ixodic ticks suggests that additional research is needed to study the potential role of ticks as carriers of these zoonotic bacteria.

Bat ectoparasites: chigger mites (Trombiculidae), ticks (Ixodidae and Argasidae), and bugs (Cimicidae) in the Eastern Palaearctic.

Nine species-level taxa of bat ectoparasites, three chigger mites (Trombiculidae), three hard (Ixodidae), and one soft tick (Argasidae) species, as well as two bug (Cimicidae) species from nine bat species hosts were detected in the Eastern Palaearctic. Trombiculid larvae of Leptotrombidium schlugerae, Leptotrombidium album, and Ascoschoengastia latyshevi were first recorded on bats in the temperate zone of eastern Russia. L. schlugerae was more abundant than A. latyshevi in the same study sites in Eastern Siberia, and the main hosts of both chigger species were Plecotus ognevi and Eptesicus nilssonii. Ixodid ticks Dermacentor marginatus, Ixodes simplex, and Ixodes sp. were sampled from bats in Kazakhstan, the Far East, and Eastern Siberia, respectively. Phylogenetic analysis based on Cox1, 16S rDNA, and ITS2 sequences of I. simplex showed that the specimens from the Far East grouped into a clade distributed in the Eastern Palaearctic and India. In turn, the specimen of Ixodes sp. from Eastern Siberia was most closely related to Ixodes soricis and Ixodes angustus with p-distance of 9.8-10.7% (Cox1), suggesting that this tick probably belongs to a new species. Argas vespertilionis larvae were collected from three widespread bat species in Kazakhstan. Two bug species, Cimex pipistrelli and Cimex aff. lectularius, were recorded in the Far East and Eastern Siberia, respectively. Specimens from Transbaikalia were morphologically identified as Cimex lectularius. However, they differed from the latter by 12.5-12.9% of Cox1 sequences, indicating that C. aff. lectularius may be a new species.

Germany-wide citizen science study reveals spread of Babesia canis-infected Dermacentor reticulatus ticks by dogs travelling within the country

The ornate dog tick Dermacentor reticulatus, vector of Babesia canis, has shown a considerable range expansion in several European countries. Previously, only few areas in Germany were recognised as endemic for B. canis, but a marked increase in autochthonous canine babesiosis cases and spread to new areas has been noted recently. To better assess the current risk for dogs, the present study screened 5913 specimens of D. reticulatus from all over Germany, collected in the frame of a Citizen Science study during 2019–2023. Moreover, 343 Dermacentor marginatus ticks were also included. Babesia detection was achieved by quantitative real-time PCR (qPCR). Positive samples were confirmed by sequencing. Moreover, a MGB-probe-based triplex qPCR was established to detect and distinguish between the canine Babesia spp. relevant in Europe, i.e. B. canis, Babesia vogeli and Babesia gibsoni. Overall, B. canis DNA was detected in five D. reticulatus specimens (0.08%). Two of the B. canis-positive ticks originated from areas previously known as endemic for canine babesiosis, namely from the area of Freiburg im Breisgau, federal state of Baden-Wuerttemberg, and from the district St. Wendel, federal state of Saarland. Three further B. canis-positive ticks were detected in districts not yet recognised as endemic, one each in the district of Mansfeld-Suedharz, federal state of Saxony-Anhalt, the district of Ravensburg, federal state of Baden-Wuerttemberg and in the city of Fürth, federal state of Bavaria. However, the tick in Fürth was found on a dog who had returned from a trip to the Breisgau region on the previous day, indicating translocation of the specimen out of this well-known endemic focus. The geographical distribution of the positive samples shows that B. canis is currently spreading in Germany, particularly via dogs travelling within the country, increasing the infection risk throughout the country. Important measures to contain a further spread of the pathogen include comprehensive year-round tick prophylaxis with licensed acaricides, not only to protect the individual pet, but also the entire dog population. Moreover, screening of dogs entering Germany from B. canis-endemic countries is required and any treatment should aim at pathogen elimination by use of appropriate imidocarb dosages.

The first lumpy skin disease outbreak in cattle in Kazakhstan

Lumpy skin disease (LSD) is an emerging trans-boundary viral disease of cattle originating from the African continent. Here, we describe the first LSD outbreak reported in the Republic of Kazakhstan in July 2016, as well as associated clinical manifestations of the disease, diagnostic methods, and control measures taken to combat further spread of the pathogen. To determine the cause of the disease, samples were taken from sick and dead animals, as well as from insects and ticks. LSDV DNA was detected by PCR in all samples from dead animals and ticks (Dermacentor marginatus and Hyalomma asiaticum), in 14.29% of samples from horseflies (Tabanus bromius), and in one of the samples from two Stomoxys calcitrans flies. The reproductive LSD virus was isolated from organs of dead cattle and insects in the culture of LT and MDBK cells. The virus accumulated in cell cultures of LT and MDBK at the level of the third passage with titers in the range of 5.5–5.75 log 10 TCID50/cm3.During the outbreak, the number of affected cattle within an epidemiological unit reached 459 cattle out of 3557 registered susceptible cattle, with 12.90% morbidity and 0.96% mortality. This manuscript presents the epidemiological situation; the diagnosis; the control measures, including mass vaccination; and the stamping out campaign.

1765. Distribution of Rickettsia species among hospitalized cases and ticks in Pavlodar region, Kazakhstan, 2019

Abstract Background Spotted Fever Group Rickettsioses (SFGR) is a group of neglected, life-threatening zoonotic diseases caused by closely related bacteria spread primarily by ticks. Treatment is available if identified, but testing for Rickettsiae is limited. Little is known about SFGR prevalence and distribution of Rickettsiae species in Kazakhstan. This knowledge can help inform SFGR prevention and treatment efforts. Methods We conducted sentinel surveillance from April to October 2019 in six hospitals in the Pavlodar region, an area where several SFGR cases had previously been detected. We interviewed and collected samples from all consenting patients ≥ 6 years old with SFRG symptoms. Parents consented for patients < 18 years old. Samples included skin lesions and two serum samples at the acute stage (AS) and convalescent stage (CS). We classified participants as having acute SFGR if they had either: (1) positive PCR, or (2) a four-fold increase in IFA IgG titers from AS to CS samples, or (3) IgG titers (≥ 1:64) in an AS sample. We also collected ticks using dragging or flagging of vegetation and tested them using real-time PCR. Results Of 105 people enrolled, 69% had acute SFGR (fig. 1). Incidence rates per 100,000 population at sentinel sites ranged from 7 to 50. Common signs were fever (100%), headache (89%), rash (75%), and myalgia (58%). R. sibirica (40%), R. raoultii (39%), and R. slovaca (7%) were identified in participants (tab. 1). Participants with R. sibirica were more likely than participants with R. raoultii to have eschar (80% vs. 7%, p < 0.01, respectively) and rash (90% vs. 61%, p=0.01, respectively). Doxycycline was administered to 64% of participants, and nobody died. R. raoultii and R. spp were identified in 9% of Dermacentor reticulatus ticks (n=610) and 7% of Dermacentor marginatus ticks (n=349). R. sibirica was identified in 1% of D. marginatus ticks. S. slovaca was not detected in ticks (fig. 2).Figure 1.Patient enrollment, specimen collection and testing results, Pavlodar region, 2019. PCR: polymerase chain reaction; RSB: rash skin biopsy or /and eschar or/and swab from eschar samples; IFA: immunofluorescence assay; AS: acute serum collected at acute phase; CS: convalescent serum collected at convalescent phase; ND: not defined. *11 – PCR negative tested with IFA. Of which, 5 had both AS and CS (results: 2-positive, 2 -negative, 1-recent infection) and 6 had AS only (results: 2-probable, 4 not defined).Table 1.Rickettsia species identified from hospitalized cases (n=72)Figure 2.Rickettsia species in ticks by selected sites (Aksu and Pavlodar districts), Pavlodar region, 2019 Conclusion There was a two-fold increase in cases detected through active surveillance during our study than reported in previous years (105 in 2019 compared to 54 in 2018 and 40 in 2017). R. sibirica and R. raoultii are the dominant species associated with SFGR in Pavlodar and are also found in local ticks. Improved disease detection and regular testing of humans and ticks in areas with SFGR cases is needed. Disclosures All Authors: No reported disclosures

Co-infection patterns in the ectoparasitic community affecting the Iberian ibex Capra pyrenaica

BackgroundSarcoptic mange is one of the main parasitic diseases affecting the Iberian ibex Capra pyrenaica. Scabietic animals suffer a decline in body condition and reproductive fitness and in severe cases may die. Although several previous studies of the pathology of this disease and the physiological changes it produces in ibex have been carried out in recent years, our knowledge of the relationship between Sarcoptes scabiei and other ectoparasites of this host is still limited.MethodsWe analysed 430 Iberian ibex skin samples. Ectoparasites were removed, counted and identified. Mite (S. scabiei) numbers were obtained after digesting the skin samples in a 5% KOH solution. We modelled mite numbers in terms of host sex and age, site, year, season and the presence of other ectoparasites such as ticks and lice using generalized linear mixed models (GLMMs) and ectoparasite co-occurrence patterns using two different models: the probabilistic model species co-occurrence and the generalized linear latent variable model (GLLVM).ResultsThe ectoparasite community was mainly composed of S. scabiei, six ticks (Haemaphysalis sulcata, Haemaphysalis punctata, Rhipicephalus bursa, Rhipicephalus turanicus, Dermacentor marginatus and Ixodes ricinus) and two lice (Bovicola crassipes and Linognathus stenopsis). Adult male ibex harboured more mites than females. Mite numbers varied greatly spatially and seasonally and increased with the presence of other parasites. Some positive co-occurrence relationships between pairs of different ectoparasites were observed, particularly between ticks. The presence of S. scabiei negatively affected lice and H. sulcata numbers.ConclusionsSarcoptic mange has spread above all in ibex populations in and around the Mediterranean Basin, where it is now found in almost a third of its host’s range. Mite numbers varied seasonally and spatially and were higher in male hosts. The presence of S. scabiei had a negative effect on lice numbers but favoured the presence of ticks.Graphical

The Prevalence of Pathogens among Ticks Collected from Livestock in Kazakhstan.

Ticks carry and transmit a wide variety of pathogens (bacteria, viruses and protozoa) that pose a threat to humans and animals worldwide. The purpose of this work was to study ticks collected in different regions of Kazakhstan for the carriage of various pathogens. The collected ticks were examined by PCR for the carriage of various pathogens. A total of 3341 tick samples parasitizing three animal species (cattle, sheep and horses) were collected at eight regions of Kazakhstan. Eight tick species were found infesting animals: Dermacentor marginatus (28.08%), Hyalomma asiaticum (21.28%), Hyalomma anatolicum (17.18%), Dermacentor reticulatus (2.01%), Ixodes ricinus (3.35%), Ixodes persulcatus (0.33%), Hyalomma scupense (12.87%) and Hyalomma marginatum (14.90%). Ticks collected from livestock animals were examined for the pathogen spectrum of transmissible infections to determine the degree of their infection. Four pathogen DNAs (lumpy skin disease virus (LSDV), Coxiella burnetti, Teileria annulata, and Babesia caballi) were detected by PCR in Dermacentor marginatus, Hyalomma asiaticum, Hyalomma scupense, Hyalomma anatolicum. The infection of ticks Dermacentor marginatus and Hyalomma asiaticum collected on cattle in the West Kazakhstan region with LSDV was 14.28% and 5.71%, respectively. Coxiella burnetti was found in the ticks Dermacentor marginatus (31.91%) in the Turkestan region and Hyalomma anatolicum (52.63%) in the Zhambyl region. Theileria annulata was found in ticks Hyalomma scupense (7.32%) and Dermacentor marginatus (6.10%) from cattle in the Turkestan region. Babesia caballi was isolated only from the species Hyalomma scupense (17.14%) in the Turkestan region. There were no PCR-positive tick samples collected from sheep. RNA/DNAs of tick-borne encephalitis virus (TBEV), African swine fever virus (ASFV), Hantavirus hemorrhagic fever with renal syndrome (HFRS), and chlamydia pathogens were not found in ticks. The new data give a better understanding of the epidemiology of tick-borne pathogens and the possibility of the emergence of tick-borne animal diseases in Kazakhstan.

Lumpy skin disease in Kazakhstan

This study describes the registration of the first cases of lumpy skin disease in July 2016 in the Republic of Kazakhstan. In the rural district of Makash, Kurmangazinsky district of Atyrau region, 459 cattle fell ill and 34 died (morbidity 12.9% and mortality 0.96%). To determine the cause of the disease, samples were taken from sick and dead animals, as well as from insects and ticks. LSDV DNA was detected by PCR in all samples from dead animals and ticks (Dermacentor marginatus and Hyalomma asiaticum), in 14.29% of samples from horseflies (Tabanus bromius), and in one of the samples from two Stomoxys calcitrans flies. The reproductive LSD virus was isolated from organs of dead cattle and insects in the culture of LT and MDBK cells. The virus accumulated in cell cultures of LT and MDBK at the level of the third passage with titers in the range of 5.5–5.75 log 10 TCID50/cm3. Sequencing of the GPCR gene allowed us to identify this virus as a lumpy skin disease virus.

Scalp eschar and neck lymphadenopathy by Rickettsia slovaca after Dermacentor marginatus tick bite case report: multidisciplinary approach to a tick-borne disease

BackgroundScalp Eschar and Neck LymphAdenopathy after Tick bite is a zoonotic non-pathogen-specific disease most commonly due to Rickettsia slovaca and Rickettsia raoultii. Diagnosis is mostly based only on epidemiological and clinical findings, without serological or molecular corroboration.We presented a clinical case in which diagnosis was supported by entomological identification and by R. slovaca DNA amplifications from the tick vector.Case presentationA 6-year-old child presented with asthenia, scalp eschar and supraclavicular and lateral-cervical lymphadenopathy. Scalp Eschar and Neck LymphAdenopathy After Tick bite syndrome following a Dermacentor marginatus bite was diagnosed. Serological test on serum revealed an IgG titer of 1:1024 against spotted fever group rickettsiae, polymerase chain reaction assays on tick identified Rickettsia slovaca. Patient was successfully treated with doxycycline for 10 days.ConclusionsA multidisciplinary approach including epidemiological information, clinical evaluations, entomological identification and molecular investigations on tick, enabled proper diagnosis and therapy.

Revisiting amino acid analyses for bioadhesives including a direct comparison of tick attachment cement (Dermacentor marginatus) and barnacle cement (Lepas anatifera)

With respect to potential applications in healthcare, pharmacy, the bonding industry, and cosmetics, biological adhesives produced from various animals are of high interest. A large number of species in the family Ixodidae produce an adhesive substance called attachment cement. This study focuses on the detailed investigation of the amino acid composition of the attachment cement from ticks (Dermacentor marginatus) and comparison with cement samples from barnacles (Lepas anatifera).Strong emphasis was laid on sample preparation of both types of cement and included the complete hydrolysis of proteins under either basic or acidic conditions. Stability of propyl chloroformate derivatives of the amino acids were measured by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS) and gas chromatography electron ionisation tandem mass spectrometry (GC-EI-MS/MS) and were validated in terms of reproducibility and precision of analyses using NIST certified amino acid as well as protein standards. For the majority of the amino acids analytically valid recovery rates between 86 and 111% were achieved using GC-EI-MS/MS analysis after acidic hydrolysis.The method was applied for direct comparison of two biological glue systems, tick and barnacle cement. An outstandingly high content of glycine was present in the tick attachment cement; as were significant concentrations of leucine, serine and proline. In contrast, high levels of leucine, serine, aspartic acid/asparagine, glycine, glutamic acid/glutamine, alanine and valine were determined for barnacle cement. None of the samples showed the presence of 3,4-dihydroxy-phenylalanine (DOPA), yet tick attachment cement exhibited significantly higher concentration levels of tyrosine, the precursor of DOPA. It can clearly be stated that published results for amino acid analysis of barnacle cement show significantly under-/overestimation for some amino acids.Distinct differences in amino acid presence and concentration were observed for the two bio-adhesives. Although both have cement-like properties the data implied that different attachment mechanisms are involved for each of the organisms.

De novo assembly and analysis of the transcriptome of the Dermacentor marginatus genes differentially expressed after blood-feeding and long-term starvation

BackgroundThe ixodid tick Dermacentor marginatus is a vector of many pathogens wide spread in Eurasia. Studies of gene sequence on many tick species have greatly increased the information on tick protective antigen which might have the potential to function as effective vaccine candidates or drug targets for eco-friendly acaricide development. In the current study, RNA-seq was applied to identify D. marginatus sequences and analyze differentially expressed unigenes.MethodsTo obtain a broader picture of gene sequences and changes in expression level, RNA-seq was performed to obtain the whole-body transcriptome data of D. marginatus adult female ticks after engorgement and long-term starvation. Subsequently, the real-time quantitative PCR (RT-qPCR) was applied to validate the RNA-seq data.ResultsRNA-seq produced 30,251 unigenes, of which 32% were annotated. Gene expression was compared among groups that differed by status as newly molted, starved and engorged female adult ticks. Nearly one third of the unigenes in each group were differentially expressed compared to the other two groups, and the most numerous were genes encoding proteins involved in catalytic and binding activities and apoptosis. Selected up-regulated differentially expressed genes in each group were associated to protein, lipids, carbohydrate and chitin metabolism. Blood-feeding and long-term starvation also caused genes differentially expressed in the defense response and antioxidant response. RT-qPCR results indicated 6 differentially expressed transcripts showed similar trends in expression changes with RNA-seq results confirming that the gene expression profiles in transcriptome data is in consistent with RT-qPCR validation.ConclusionsObtaining the sequence information of D. marginatus and characterizing the expression pattern of the genes involved in blood-feeding and during starvation would be helpful in understanding molecular physiology of D. marginatus and provides data for anti-tick vaccine and drug development for controlling the tick.Graphical

In-vitro anticandidial efficacy of tick egg wax from Hyalomma marginatum, Rhipicephalus bursa and Dermacentor marginatus

Objective: In the previous studies, the antibacterial, antifungal, and antiviral efficacy of the tick egg wax-coating of certain tick species wereexamined and some significant results were obtained. However, related researches and studied tick species are limited. There are hundredsof tick species, and it is well known that the antimicrobial efficacy of the wax is closely related to the species. The aim of this study was toinvestigate the in-vitro anticandidial efficacy of the egg waxes belonging to three tick species, which have not been studied before and havequite different biological and ecological differences.Methods: In the study, the egg waxes of the tick species, Hyalomma marginatum, Rhipicephalus bursa, and Dermacentor marginatus, wereused on Candida albicans ATCC10231, Candida parapsilosis ATCC 22019, and Candida tropicalis ATCC 750. Antimycotic susceptibility test wascarried out in accordance with the Clinical and Laboratory Standards Institute (CLSI) recommendations using the M27-A3 microdilution method.Results: It was determined that the wax of Rhipicephalus bursa has inhibitory effect on Candida tropicalis ATCC 750 in a particular concentration,and no significant effects were observed in other trials.Conclusion: Anticandidial effect obtained from the egg wax of R. bursa can be associated with some distinctive biological characteristics, and itwas concluded that the detailed studies with different tick species might yield significant results for the discovery of new generation antifungals.

Lymphadenopathy transmitted by tick. A pediatric case of rickettsiosis in primary care

The entity called tick-borne lymphadenopathy, also known as dermacentor-borne necrosis eritema lymphadenopathy, is included in the differential diagnosis of diseases transmitted by ticks, which have increased considerably in recent years due to greater clinical-epidemiological observation and diagnostic improvement. It is a zoonosis caused by Rickettsia slovaca and transmitted by the bite of the Dermacentor marginatus tick. Affected patients have a necrotic eschar surrounded by an erythematous halo in the scalp, as well as painful regional lymphadenopathy. We present a seven-year-old male who shows, after the extraction of a tick, a necrotic eschar on the scalp, accompanied by lymphadenopathy and low-grade fever. The study of polymerase chain reaction and culture of the lesion confirm the presence of Rickettsia slovaca. The patient received oral azithromycin with a good response. In Primary Care, it is important to monitor the tick bites, to detect possible diseases transmitted by them.

Uptake and fecal excretion of Coxiella burnetii by Ixodes ricinus and Dermacentor marginatus ticks

BackgroundThe bacterium Coxiella burnetii is the etiological agent of Q fever and is mainly transmitted via inhalation of infectious aerosols. DNA of C. burnetii is frequently detected in ticks, but the role of ticks as vectors in the epidemiology of this agent is still controversial. In this study, Ixodes ricinus and Dermacentor marginatus adults as well as I. ricinus nymphs were fed on blood spiked with C. burnetii in order to study the fate of the bacterium within putative tick vectors.MethodsBlood-feeding experiments were performed in vitro in silicone-membrane based feeding units. The uptake, fecal excretion and transstadial transmission of C. burnetii was examined by quantitative real-time PCR as well as cultivation of feces and crushed tick filtrates in L-929 mouse fibroblast cells and cell-free culture medium.ResultsTicks successfully fed in the feeding system with engorgement rates ranging from 29% (D. marginatus) to 64% (I. ricinus adults). Coxiella burnetii DNA was detected in the feces of both tick species during and after feeding on blood containing 105 or 106 genomic equivalents per ml blood (GE/ml), but not when fed on blood containing only 104 GE/ml. Isolation and cultivation demonstrated the infectivity of C. burnetii in shed feces. In 25% of the I. ricinus nymphs feeding on inoculated blood, a transstadial transmission to the adult stage was detected. Females that molted from nymphs fed on inoculated blood excreted C. burnetii of up to 106 genomic equivalents per mg of feces.ConclusionsThese findings show that transstadial transmission of C. burnetii occurs in I. ricinus and confirm that I. ricinus is a potential vector for Q fever. Transmission from both tick species might occur by inhalation of feces containing high amounts of viable C. burnetii rather than via tick bites.

Establishing a Cultivable Cell Line of the Tick Dermacentor marginatus

Owing to the changes in the general ecological situation in Russia, livestock losses from ovine anaplasmosis have rapidly increased in recent years. The development of a vaccine against this disease is therefore all the more relevant. A continuous culture of tick cells could be used as an appropriate substrate for producing biomass of the pathogen of ovine anaplasmosis, Anaplasma ovis, for the purpose of manufacturing a cell-cultural inactivated vaccine. Such a continuous cell line of the tick Dermacentor marginatus, the definitive reservoir host of A. ovis, has been obtained by cultivation of homogenized tick eggs on a modified Leibovitz medium L15. The established cell line DM-77 has an undifferentiated phenotype: the cells are rounded, with large nuclei and well-visible nucleoli. By the end of the study, the cell line was passaged eight times and did not express signs of growth rate decrease. The duplication time was 2.8 ± 0.3 days for cultivation in a medium with 10% fetal serum at 32°C.

Molecular characterization and phylogenetic analysis of Babesia and Theileria spp. in ticks from domestic and wild hosts in Sardinia

Piroplasmoses are tick-borne protozoan diseases caused by hemoprotozoan parasites with considerable economic, veterinary and medical impact worldwide. Here, the presence and diversity of piroplasmids was investigated in ticks collected from domestic and wild hosts in a typical subtropical environment of Sardinia island by standard PCR, sequencing, and phylogenetic analyses. We demonstrate the presence of strains closely related to the Theileria buffeli/sergentii/orientalis complex in Rhipicephalus sanguineus s.l., Rh. bursa, Rh. annulatus, Hyalomma marginatum, Dermacentor marginatus and Haemaphysalis punctata ticks. A strain detected in two Rh. sanguineus s.l. ticks collected from dogs grouped with T. equi, the agent of equine piroplasmosis. T. ovis, the main etiological agent of ovine theileriosis, was detected in one Rh. bursa tick from a mouflon. Babesia bigemina, the causative agent of bovine babesiosis, was detected in two Rh. sanguineus s.l. ticks from dogs. Our findings expand the knowledge on the repertoire of tick-borne pathogens present in Mediterranean ticks. Further analyses are needed to determine the role of ticks in the biological or mechanical transmission of piroplasmoses in this area.

Tissue localization of Coxiella-like endosymbionts in three European tick species through fluorescence in situ hybridization

Ticks are commonly infected by Coxiella-like endosymbionts (Coxiella-LE) which are thought to supply missing B vitamin nutrients required for blood digestion.While this nutritional symbiosis is essential for the survival and reproduction of infected tick species, our knowledge of where Coxiella-LE is localized in tick tissues is partial at best since previous studies have focused on a limited number of Asian or American tick species. To fill this gap, we investigated the tissue localization of Coxiella-LE in three European tick species, Ornithodoros maritimus, Dermacentor marginatus and Ixodes hexagonus, using a diagnostic fluorescence in situ hybridization (FISH) assay, combined with PCR-based detection. Specific fluorescent foci were observed in several tick tissues. We visualized a pronounced tissue tropism of Coxiella-LE for tick ovaries and Malpighian tubules, a pattern suggestive of a high degree of lifestyle specialization toward mutualism: infection of the ovaries is indicative of transovarial transmission, whereas infection of the Malpighian tubules suggests a nutritional function. We postulate that Malpighian tubules are key organs for the nutritional symbiosis, notably the synthesis of B vitamins by Coxiella-LE, whereas the infection of the ovaries ensures vertical transmission of the symbionts to future generations. We also detected occasional infections in other organs, such as salivary glands and the midgut. Finally, we discuss the potential significance of the different tissue tropism for tick biology.

Ticks from wild mammals: evidence of zoonotic pathogens in Liguria region, North-West Italy

Purpose: Pathogens of the genera Anaplasma, Borrelia and Rickettsia, and Tick-borne Encephalitis virus (TBEV) may be associated to various tick species which are hematophagous ectoparasites potentially hosted by any terrestrial vertebrate, humans included. This peculiarity makes ticks potential horizontal vectors of zoonotic importance. Liguria is characterized by mountains and an intense urbanization of the terminal part of the alluvial plains. The 12% of its surface is a protected natural area. The aim of our study is to provide an overview of the infection rate of tick-borne agents by analyzing ticks collected between 2016 and 2017 from wild mammals in Liguria. Methods & Materials: More than 200 ticks (124 Ixodes, 68 Dermacentor, 34 Haemaphysalis and 9 Riphicephalus spp.) were collected from 49 roe deer (Capreolus capreolus), 41 wild boars (Sus scrofa), 7 chamois (Rupicapra rupicapra), 2 fallow deer (Dama dama) and 1 marten (Martes foina) and stored in 70% ethanol. After ticks identification and total nucleic acid extraction, simplex PCR assays to detect Anaplasma, Borrelia, Rickettsia spp. and TBE virus were performed. By project's design, all ticks belonging to a given species from the same animal and collection date were pooled and treated as a single sample. Results: PCR results revealed 36 ticks positive for Rickettsia spp. and 3 for Anaplasma spp.; all samples were negative for Borrelia spp. and TBEV. Rickettsia spp. were found in 32 Ixodes ricinus and 4 Dermacentor marginatus ticks, while Anaplasma spp. were related to 2 Haemaphysalis punctata and 1 Ixodes ricinus (co-infected with Rickettsia). Regarding the host species, the 15% of wild boars and 61% of roe deer sampled were carrying ticks infected with Rickettsia, while the 29% of chamois ticks infected with Anaplasma. Conclusion: Our study confirms the presence of Rickettsia and Anaplasma spp. in ticks in Liguria, giving proof of their circulation in wild mammals. This panorama suggests the importance of taking forward the health monitoring in order to ensure the early detection of potential zoonotic infections in this area.

A metagenomic survey of ticks reveals pathogenic rickettsia and francisella/coxiella-like endosymbionts in Anatolia

Purpose: We investigated tick-borne bacteria in field-collected ticks via a metagenomic approach using high throughput sequencing. Methods & Materials: A total of 210 ticks, collected from various regions of Anatolia, were identified morphologically and processed in 39 pools. Homogenization, nucleic acid purification and library preparation in pools were performed using standard assays and protocols, followed by sequencing using the Illumina MiSeq system. Results: A near-complete Rickettsial genome of 1.485.148 nucleotides with 89,5% identity to Rickettsia felis strain URRWXCal2 was assembled from a pool of Haemaphysalis parva ticks. The identical pool further provided a 5690-nucleotide sequence of the Rickettsial conjugative plasmid. Varying lengths of 16S, OmpA, Sca1 and gltA sequences were obtained from 7 tick pools (17,9%) comprising Haemaphysalis parva, Rhipicephalus bursa, Rhipicephalus sanguineus sensu lato and Hyalomma marginatum ticks. The sequences were characterized as Rickettsia felis and Rickettsia hoogstraalii in 5 pools whereas strain identification remained obscure in two pools. 16S rRNA sequences of Coxiella-like endosymbionts were detected in 15 pools (38,4%) of Haemaphysalis parva, Rhipicephalus bursa, Rhipicephalus sanguineus s. l., Hyalomma marginatum, Hyalomma excavatum and Dermacentor marginatus ticks. These sequences formed three phylogenetically-distinct clusters with previously-characterized Coxiella-like endosymbionts from Rhipicephalus, Ixodes and Dermacentor species. Finally, Francisella-related 16S sequences were characterized in 9 pools (23%) of Rhipicephalus sanguineus s. l., Hyalomma marginatum, Dermacentor marginatus and Hyalomma aegyptium ticks. These sequences formed two distinct clusters and grouped with Francisella-like endosymbionts of Dermacentor ticks, sharing a common ancestor with Francisella percica. Conclusion: Rickettsia of the spotted fever - Rickettsia akari group were characterized in this preliminary tick screening study, with detailed sequence information obtained for various strains. Widespread infection of ticks with Francisella- and Coxiella-like symbionts were also identified. The impact of these endosymbiotic bacteria on the circulation and detection of pathogenic strains in ticks requires further investigation.

Diversity of Rickettsia species in border regions of northwestern China

BackgroundRickettsia species belonging to the spotted fever group (SFG) cause infections in humans, domestic animals and wildlife. At least ten SFG Rickettsia species are known to occur in China. However, the distribution of rickettsiae in ticks and fleas in the border region of northwestern China have not been systematically studied to date.ResultsA total of 982 ticks (Rhipicephalus turanicus, Dermacentor marginatus, D. nuttalli and Haemaphysalis punctata) and 5052 fleas (18 flea species from 14 species of wild mammals) were collected in ten and five counties, respectively, of Xinjiang Uygur Autonomous Region (northwestern China). Tick and flea species were identified according to morphological and molecular characteristics. Seven sets of primers for amplifying the 17-kDa antigen gene (17-kDa), citrate synthase gene (gltA), 16S rRNA gene (rrs), outer membrane protein A and B genes (ompA, ompB), surface cell antigen 1 gene (sca1) and PS120-protein encoding gene (gene D) were used to identify the species of rickettsiae. Nine Rickettsia species have been detected, seven of them in ticks: R. aeschlimannii, R. conorii, R. raoultii, Rickettsia sibirica, R. slovaca, R. massiliae and “Candidatus R. barbariae”. In addition, R. bellii and two genotypes of a rickettsia endosymbiont (phylogenetically in an ancestral position to R. bellii) have been detected from flea pools.ConclusionsThis study provides molecular evidence for the occurrence of several SFG rickettsiae in Rhipicephalus turanicus, Dermacentor nuttalli and D. marginatus. Furthermore, R. bellii and two ancestral rickettsia endosymbionts are present in fleas infesting wild rodents in the border regions of northwestern China. These data extend our knowledge on the diversity of rickettsiae in Central Asia.