Diversity and geographic distribution of rickettsial agents identified in brown dog ticks from across the United States

Rhipicephalus sanguineus sensu lato, or brown dog ticks, transmit a variety of pathogens of veterinary and public health importance globally. Pathogens vectored by brown dog ticks and identified in the United States include Babesia vogeli, Ehrlichia canis, and several spotted fever group Rickettsia spp. (SFGR). Due to the challenge of collecting canine blood samples nationwide to screen for exposure to these pathogens, we took an indirect approach and tested brown dog ticks for molecular evidence of infection. Brown dog ticks (616 adults and 65 nymphs) collected from dogs and cats across the nation were tested by separate PCR assays detecting Babesia spp., E. canis, and SFGR. While no Babesia sp. was found, we identified rickettsial agents in 3.5% (24/681; 95% CI 2.4–5.2%) of the ticks. Pathogens and related organisms detected in ticks included E. canis (n = 1), Rickettsia amblyommatis (n = 3), Rickettsia massiliae (n = 11), Rickettsia monacensis (n = 3), Rickettsia montanensis (n = 5), and an undefined Rickettsia species (n = 1). These data demonstrate a wider geographic distribution of R. massiliae than previously known, and to the authors’ knowledge, reports R. monacensis in brown dog ticks for the first time. Due to the close association that brown dog ticks have with domestic dogs and humans, more research is needed to understand the full array of organisms, some of which are zoonotic, potentially transmitted by this widespread tick complex.     

Investigation on haplotypes of ixodid ticks and retrospective finding of Borrelia miyamotoi in bank vole (Myodes glareolus) in Switzerland

The current status of tick species, important tick-borne bacteria and protozoan parasites is well-documented in Switzerland. However, reports on the genetic diversity and geographical relationships of tick species in this country appear to be in part lacking or outdated. Thus, the aim of this study was to collect ticks from various host species in southern Switzerland, to compare them in a geographical context and to screen in these samples rare tick-borne pathogens hitherto not reported or having low prevalence in Switzerland.In 2019–2020 altogether 177 ixodid ticks were collected from the vegetation, as well as from humans (n = 17), dogs (n = 23), cats (n = 41), red deer (n = 8), a European rabbit and a European hedgehog at 25 locations in three cantons of south Switzerland. Tick species were identified morphologically, followed by DNA extraction and comparison of mitochondrial haplotypes with molecular-phylogenetic methods. Tick DNA extracts, as well as sixty-two rodent liver or spleen tissue DNA extracts (representing six species) available from 2005 to 2006 were screened for trypanosomes, Occidentia massiliensis and Borrelia miyamotoi.Morphologically, three tick species were identified: Ixodes ricinus (n = 170), Rhipicephalus sanguineus sensu lato (n = 6) and I. hexagonus (n = 1). In contrast to companion animals (dogs, cats) immature ticks (larvae and nymphs) predominated on humans, which was a highly significant association (P < 0.0001). Molecular comparison of the cytochrome c oxidase subunit I (cox1) gene with GenBank data established the species as R. sanguineus sensu stricto and confirmed I. hexagonus, both showing 99.8–100% sequence identity to conspecific ticks from northern Italy. Seventy-nine specimens morphologically identified as I. ricinus revealed high 16S rRNA gene haplotype diversity and represented two phylogenetic groups. Two I. ricinus haplotypes from Switzerland belonged to the same haplogroup with I. inopinatus from Spain, Germany and Austria as well as with I. ricinus reported from a broad geographical range of Europe (including Italy, the Netherlands, Poland, Latvia and Sweden). All 141 tick DNA extracts (from five R. sanguineus s.l., 135 I. ricinus and one I. hexagonus) and 62 rodent tissue DNA extracts were negative for trypanosomes and O. massiliensis. However, B. miyamotoi was identified in a bank vole (Myodes glareolus) and three ticks by sequencing.From Switzerland, this is the first report of tick haplotypes that are phylogenetically closely related to I. inopinatus. However, based on their morphology, both specimens are considered as I. ricinus. These results highlight the importance that the identification of I. inopinatus should be based on coherent morphologic and molecular properties. This is also the first report of rodent-borne B. miyamotoi in Switzerland. Taking into account the year of collection (2005), in a chronological order this might be the first indication of B. miyamotoi in any rodent species in Europe.     

Detection of Leishmania infantum,Babesia canis,and rickettsiae in ticks removed from dogs living in Italy

The aims of this study were to determine natural infections by Anaplasma phagocytophilum/Anaplasma platys, Bartonella henselae, Ehrlichia canis, Leishmania infantum, Rickettsia spp., Babesia spp., and Hepatozoon spp. by molecular methods in ticks (n = 91) removed from dogs with clinical signs and laboratory abnormalities compatible with tick-borne diseases (n = 22) living in Italy and to assess the distribution and species of ticks encountered. Ticks from dogs living in southern Italy were all identified as Rhipicephalus sanguineus (n = 25), ticks from central Italy included Rh. sanguineus (n = 8) and Ixodes ricinus (n = 9), ticks from northern Italy included Rh. sanguineus (n = 45), Dermacentor marginatus (n = 3), and one I. ricinus. Leishmania infantum, Rickettsia spp., and Babesia canis were the only pathogens detected in 7 (8%), 4 (4%), and 2 (2%) out of 91 ticks, respectively. L. infantum was detected in I. ricinus from central Italy and in Rh. sanguineus from northern and central Italy. Rickettsia conorii and Ri. massiliae were detected in Rh. sanguineus ticks from central and southern Italy (Sicily), respectively. Bab. canis was detected in D. marginatus ticks from northern Italy.     

The brown dog tick Rhipicephalus sanguineus sensu Roberts, 1965 across Australia: Morphological and molecular identification of R. sanguineus s.l. tropical lineage

The brown dog tick Rhipicephalus sanguineus (Latreille, 1806) is the most widely distributed tick species globally. Throughout the world there are at least two divergent lineages on dogs that are traditionally grouped into what was known as R. sanguineus. The species R. sanguineus was recently redescribed using a neotype reported from countries with a temperate climate. The second lineage distributed in countries with primarily tropical climates is currently designated R. sanguineus s.l. tropical lineage. Here, we present a comprehensive genetic evaluation of Australian brown dog ticks from across the continent that complements the morphological study of R. sanguineus sensu Roberts (1965). A total of 294 ticks were collected from dogs around Australia ― including New South Wales, Queensland, the Northern Territory and Western Australia ― for morphological identification. All ticks were morphologically identified as R. sanguineus sensu Roberts (1965). DNA was isolated from a single leg from morphologically characterised individuals from New South Wales (n = 14), Queensland (n = 18), Northern Territory (n = 7) and Western Australia (n = 13), together with ticks from Fiji (n = 1) and the Seychelles (n = 1) for comparison with Australian ticks. The study revealed three cox1 haplotypes clustered only with R. sanguineus s.l. tropical lineage’. An updated distribution of R. sanguineus sensu Roberts (1965) is compared to the 1965 distribution. In the Australian context, R. sanguineus s.l. has appeared in north-western New South Wales but remains absent from coastal New South Wales. Despite both temperate and tropical climates being present in Australia, only R. sanguineus s.l. tropical lineage was found. The evidence does not support the presence of the strictly defined brown dog tick, R. sanguineus by Nava et al. (2018) in Australia, because the examined ticks are genetically and morphologically distinct. We recommend using the term brown dog tick, R. sanguineus sensu Roberts (1965) for specimens from Australia.     

Ticks in the metropolitan area of Berlin,Germany

A high-resolution city map showing the geographic distribution of 12 tick species (Acari: Argasidae, Ixodidae) that have been recorded from the metropolitan area of Berlin, Germany is presented. A total of 237 tick locations was mapped. These include ten ixodid tick species: Dermacentor reticulatus, Haemaphysalis concinna, Hyalomma rufipes, Ixodes ricinus, Ixodes canisuga, Ixodes hexagonus, Ixodes arboricola, Ixodes frontalis, Ixodes trianguliceps and Rhipicephalus sanguineus sensu lato. The two tick species Hy. rufipes and R. sanguineus s.l. are not endemic to Berlin. Hyalomma rufipes ticks are introduced in Europe with migratory birds from Africa every spring. Rhipicephalus sanguineus s.l. are introduced to Central Europe with dogs that had travelled to or were imported from countries where this tick is endemic. In Germany, they are able to develop and reproduce inside heated buildings. Occurrences of two soft tick species, the pigeon tick Argas reflexus and the short-legged bat tick Carios vespertilionis were also mapped. Other tick species that are likely to be endemic to Berlin and its environs, but for which documented findings or geographical coordinates are lacking, are mentioned. These include the long-legged bat tick I. vespertilionis and the marten tick I. rugicollis documented in Brandenburg, the federal state surrounding Berlin. It can be assumed that if appropriate field studies are carried out, these tick species will also be found in the metropolitan area of Berlin. The high-resolution mapping of all tick species found in a city (like Berlin) forms the basis for further investigations into the impact of climate change and changing land use on ticks and tick-borne diseases, precisely in those habitats where most people will live in the future.     

Rickettsia spp. in Rhipicephalus sanguineus sensu lato ticks collected from stray dogs in Kerman city,Iran

Rickettsial diseases are recognized as one of the most important vector-borne infectious diseases for humans all over the world. Dogs and their ticks are considered the most important reservoirs for Rickettsia spp., especially in spotted fever group rickettsioses. The aim of the study was to investigate Rickettsia infections in ticks collected from stray dogs in southeastern Iran. In this study, 50 stray dogs in Kerman city were randomly selected, of 68% and 52% of which were above 8 months age and male, respectively. Ticks were collected from the dog skins. After identification of collected ticks, genomic DNA of all ticks was extracted. DNA samples were tested using real-time PCR for Rickettsia spp. infections. The species of Rickettsia in positive samples were determined using gltA gene amplification and sequencing. A total of 250 ticks were collected from 50 stray dogs and all of them belonged to Rhipicephalus sanguineus sensu lato. Totally, 10 pooled of 50 pooled ticks were positive for Rickettsia spp. in real-time PCR and the minimal Rickettsial infection rate was 4% in this study. The identified Rickettsia spp. included R. massiliae (n = 5), R. rhipicephali (n = 1), and R. sibirica (n = 1). In this study, molecular evidence of Rickettsia spp. infection was observed in collected ticks from stray dogs in southeast Iran. More sensitivity to human and animal health care systems in southeastern Iran is essential to the diagnosis of suspected clinical cases that are related to rickettsiosis.     

Ixodid tick species found in northern Sweden – Data from a frontier area

Environmental and climatic changes in northern Europe have shaped a geographical area in which new tick species may become established and introduce new tick-borne pathogens. In recent decades, ticks have expanded their latitudinal and altitudinal range limits in northern Sweden. In this study, ticks were collected in 2018 and 2019 in northern Sweden from different hosts, mainly from dogs, cats and humans. The ticks in 2018 (n = 2141, collected from 65 municipalities in 11 provinces) were identified as Ixodes ricinus (n = 2108, 98.5%), Ixodes persulcatus (n = 18, 0.8%), Ixodes trianguliceps (n = 14, 0.7%) and Hyalomma marginatum (n = 1, 0.05%). The ticks collected in 2019 (n = 519, across a smaller area than in 2018, i.e. Sweden's four northernmost provinces) were identified as I. ricinus (n = 242, 46.6%) and I. persulcatus (n = 277, 53.4%). Among those collected in 2019, the majority of I. ricinus (n = 111, 45.9%) were submitted from the province of Västerbotten, while most I. persulcatus (n = 259, 93.5%) were collected in the province of Norrbotten. This study provides updated figures on the geographical distribution of two Ixodes species in northern Sweden. The results confirmed I. ricinus to be the dominant species and that I. persulcatus has enlarged its distributional area compared with previous reports. Updated knowledge of tick distribution is fundamental for the creation of risk maps and will allow relevant advice to be provided to the general public, suggesting measures to prevent tick bites and consequently tick-borne diseases.     

Distribution of ticks in Bosnia and Herzegovina

Ticks are one of the important groups of parasites, whose populations have increased in Europe in the last 20 years and, as vectors of many emerging diseases, are a major threat to human and animal health. Bosnia and Herzegovina has both climate and environmental conditions favorable for ticks. Given this risk, the aim of this study was to identify tick species currently present in this country and to compare the findings with previous studies, in order to update information on their spatial distribution and other parameters of occurrence.From March 2017 to April 2020, ticks were collected in 42 sampling areas (municipalities) throughout the country. Prespecified identification keys were used for identifying the ticks to the species level.A total of 6193 tick specimens from the Ixodidae family were collected from animal hosts or from vegetation. Ixodes ricinus was the most dominant tick species found. However, our results indicate a decrease in the relative contribution of this tick species to the overall abundance of tick populations. Dermacentor marginatus, which almost doubled in abundance compared to earlier studies, is the second most common tick species. We further confirmed the presence of Dermacentor reticulatus, Rhipicephalus bursa, Rhipicephalus sanguineus sensu lato, Hyalomma marginatum and Haemaphysalis punctata. Ixodes hexagonus, Ixodes canisuga and Haemaphysalis concinna, which were previously reported at low abundance were not found amongst our specimens.     

A practical protocol to prepare paraffin-embedded whole tick histology sections

Ticks are important ectoparasites that are capable of transmitting multiple classes of pathogens and are currently linked with many emerging tick-borne diseases worldwide. With increasing occurrences of tick-borne diseases in both humans and veterinary species, there is a continuous need to further our understanding of ticks and the pathogens they transmit. Whole tick histology provides a full scope of the tick internal anatomy, allowing researchers to examine multiple organs of interest in a single section. This is in contrast to other techniques that are more commonly utilized in tick-borne disease research, such as electron microscopy and light microscopy of individual organs. There is a lack of literature describing a practical technique to process whole tick histologic sections. Therefore, the current study aims to provide researchers with a workable protocol to prepare high quality paraffin-embedded whole tick histology sections. Amblyomma americanum adults were used as an example species for this study. After a series of pilot experiments using a combination of various fixatives, softening agents and processing techniques, we elected to compare two common fixatives, 10% neutral-buffered formalin (NBF) and Bouin's solution for whole ticks. Equal numbers of A. americanum unfed adults (n = 10/fixative) were processed identically and their whole tick histology coronal sections were individually scored. Higher scores were assigned to whole tick sections that contained more internal organs that are crucial for tick-borne disease research (e.g. salivary glands and midgut), high integrity of tissues and exoskeleton on the section, and good fixation and staining quality of the tissues. The mean total scores for Bouin's-fixed ticks were significantly higher compared to NBF-fixed ticks (p = 0.001). To further assess our preferred technique, we also demonstrated the feasibility of producing high quality whole tick sections for three other common tick species of medical importance (Rhipicephalus sanguineus, Ixodes scapularis, and Dermacentor variabilis) using Bouin's solution. While this technique may require further optimization for other tick species, we described a feasible protocol that uses commonly available tools, reagents and standard histologic equipment. This should allow any investigator to easily make adjustments to this protocol as needed based on their experimental goals.     

Vector competence of Rhipicephalus sanguineus sensu stricto for Anaplasma platys

Anaplasma platys is a Gram-negative, obligate intracellular bacteria that causes canine infectious cyclic thrombocytopenia in dogs. The brown dog tick Rhipicephalus sanguineus sensu lato is presumed to be the vector of A. platys based on the overlap in distribution of R. sanguineus and A. platys infections, detection of A. platys DNA in both flat and engorged field-collected R. sanguineus, and the fact that dogs are primary hosts of both brown dog ticks and A. platys. However, the only study evaluating the vector competence of R. sanguineus for A. platys under controlled laboratory conditions reported an apparent inability of ticks to acquire or maintain the pathogen. In 2016, engorged female Rhipicephalus sanguineus sensu stricto ticks were collected off dogs to start a laboratory tick colony. After one generation of colony maintenance on tick-naïve and pathogen-free New Zealand White rabbits, a rabbit used to feed F1 adults seroconverted to Anaplasma phagocytophilum antigen. PCR and subsequent DNA sequencing identified the presence of A. platys in both the adult ticks fed on this rabbit and their resulting F2 progenies. Retrospective testing of all previous (P and F1) life stages of this colony demonstrated that the infection originated from one field-collected A. platys-infected female whose progeny was propagated in the laboratory and produced the PCR-positive F1 adults. Over the following (F2-F4) generations, the prevalence of A. platys in this colony reached 90–100 % indicating highly efficient transovarial and horizontal transmission, as well as transstadial maintenance, of this pathogen by R. sanguineus s.s.     

Influence of tick sex and geographic region on the microbiome of Dermacentor variabilis collected from dogs and cats across the United States

As tick-borne diseases continue to increase across North America, current research strives to understand how the tick microbiome may affect pathogen acquisition, maintenance, and transmission. Prior high throughput amplicon-based microbial diversity surveys of the widespread tick Dermacentor variabilis have suggested that life stage, sex, and geographic region may influence the composition of the tick microbiome. Here, adult D. variabilis ticks (n = 145) were collected from dogs and cats from 32 states with specimens originating from all four regions of the United States (West, Midwest, South, and Northeast), and the tick microbiome was examined via V4-16S rRNA gene amplification and Illumina sequencing. A total of 481,246 bacterial sequences were obtained (median 2924 per sample, range 399–11,990). Fifty genera represented the majority (>80%) of the sequences detected, with the genera Allofrancisella and Francisella being the most abundant. Further, 97%, 23%, and 5.5% of the ticks contained sequences belonging to Francisella spp., Rickettsia spp., and Coxiella spp., respectively. No Ehrlichia spp. or Anaplasma spp. were identified. Co-occurrence analysis, by way of correlation coefficients, between the top 50 most abundant genera demonstrated five strong positive and no strong negative correlation relationships. Geographic region had a consistent effect on species richness with ticks from the Northeast having a significantly greater level of richness. Alpha diversity patterns were dependent on tick sex, with males exhibiting higher levels of diversity, and geographical region, with higher level of diversity observed in ticks obtained from the Northeast, but not on tick host. Community structure, or beta diversity, of tick microbiome was impacted by tick sex and geographic location, with microbiomes of ticks from the western US exhibiting a distinct community structure when compared to those from the other three regions (Northeast, South, and Midwest). In total, LEfSe (Linear discriminant analysis Effect Size) identified 18 specific genera driving these observed patterns of diversity and community structure. Collectively, these findings highlight the differences in bacterial diversity of D. variabilis across the US and supports the interpretation that tick sex and geographic region affects microbiome composition across a broad sampling distribution.     

Species richness and adaptation of the invasive cattle tick,Rhipicephalus microplus (Acari: Ixodidae) on camps grazed by sheep in the Eastern Cape Province,South Africa

The seasonal dynamics and distribution of ticks play a pivotal role in the epidemiology of tick-borne diseases. The objective of this study was to establish the seasonal abundance and species richness of questing ixodid ticks on Amathole Montane Grassland camps grazed by sheep. Ticks questing for hosts were collected monthly for a period of three years by dragging flannel strips attached to a wooden spar over the vegetation. At each occasion, six replicate drag-samples were made in camps grazed by sheep. Of the questing ticks (n = 14 891) collected from the vegetation, the most abundant larvae were those of Rhipicephalus microplus (95.04%) followed by Rhipicephalus appendiculatus (2.32%), Rhipicephalus evertsi (1.56%), Rhipicephalus decoloratus (1.03%), Rhipicephalus simus (0.03) and Amblyomma hebraeum (0.02%). Comparing the two Rhipicephalus (Boophilus) spp., R. microplus (98.9%) outcompete the indigenous tick, R. decoloratus (1.1%). The R. microplus larvae were significantly higher (P < 0.05) in 2015 (2.11±0.108), 2016 (2.02 ± 0.076) and 2017 (1.94±0.075) during spring than any other season. There were no significant differences (P ? 0.05) from R. appendiculatus questing ticks collected in autumn (0.27±0.007; 0.30±0.052) and spring (0.33±0.007; 0.20±0.052) for 2015 and 2016, respectively. The study showed that the cattle tick, R. microplus adapted very well on host species, in this case sheep, and encroached to areas that were too cold for its adaptation.     

Constituting a glutathione S-transferase-cocktail vaccine against tick infestation

Cocktail vaccines are proposed as an attractive way to increase protection efficacy against specific tick species. Furthermore, such vaccines made with different tick antigens have the potential of cross-protecting against a broad range of tick species. However, there are still limitations to the selection of immunogen candidates. Acknowledging that glutathione S-transferases (GSTs) have been exploited as vaccines against ticks and other parasites, this study aimed to analyze a GST-cocktail vaccine as a potential broad-spectrum tick vaccine. To constitute the GST-cocktail vaccine, five tick species of economic importance for livestock industry were studied (Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus microplus, Amblyomma variegatum, and Haemaphysalis longicornis). Tick GST ORF sequences were cloned, and the recombinant GSTs were produced in Escherichia coli. rGSTs were purified and inoculated into rabbits, and the immunological response was characterized. The humoral response against rGST-Rd and rGST-Av showed a stronger cross-reactivity against heterologous rGSTs compared to rGST-Hl, rGST-Ra, and rGST-Rm. Therefore, rGST-Rd and rGST-Av were selected for constituting an experimental rGST-cocktail vaccine. Vaccination experiment in rabbits showed that rGST-cocktail caused 35% reduction in female numbers in a Rhipicephalus sanguineus infestation. This study brings forward an approach to selecting immunogens for cocktail vaccines, and the results highlight rGST–Rd and rGST-Av as potentially useful tools for the development of a broad-spectrum tick vaccine.     

Ticks and tick-borne rickettsiae from dogs in El Salvador,with report of the human pathogen Rickettsia parkeri

Twelve tick species have been reported in El Salvador; however, information regarding ticks infesting domestic dogs is lacking, and pathogenic tick-borne Rickettsia species have never been reported in El Salvador. This work evaluated ticks infesting 230 dogs from ten municipalities in El Salvador from July 2019 to August 2020. A total of 1,264 ticks were collected and identified into five species: Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus microplus, Amblyomma mixtum, Amblyomma ovale, and Amblyoma cf. parvum. The tick R. sanguineus s.l. was the most frequent species in all localities (81.3% of sampled dogs), followed by Amblyomma mixtum (13.0%), Amblyomma ovale (10.9%) and Amblyomma cf. parvum (10.4%). The overall mean intensity of tick infestation was 5.5 ticks/dog. The highest specific mean intensity value was for R. sanguineus s.l. (4.8 ticks/dog), varying from 1.6 to 2.7 ticks/dog for the three Amblyomma species. From a random sample of 288 tick specimens tested molecularly for the presence of rickettsial agents, three spotted fever group Rickettsia were detected: Rickettsia amblyommatis in 90% (36/40) A. mixtum, 46% (11/24) A. cf. parvum, 4% (7/186) R. sanguineus s.l., and 17% Amblyomma spp.; Rickettsia parkeri strain Atlantic rainforest in 4% (1/25) A. ovale; and an unnamed rickettsia agent, designated as ‘Rickettsia sp. ES-A.cf.parvum’, in 4% (1/24) A. cf. parvum. Our finding of R. parkeri strain Atlantic rainforest in A. ovale is highly relevant because this agent has been associated to spotted fever illness in other Latin American countries, where A. ovale is implicated as its main vector. These findings suggest that spotted fever cases caused by R. parkeri strain Atlantic rainforest could be occurring in El Salvador.     

Comprehensive screening of tick-borne microorganisms indicates that a great variety of pathogens are circulating between hard ticks (Ixodoidea: Ixodidae) and domestic ruminants in natural foci of Anatolia

Grazing domestic ruminants serve as important reservoirs and/or amplificatory hosts in the ecology of tick-borne pathogens (TBPs) and tick vectors in the natural foci; however, many enzootic life cycles including ruminants and ticks are still unknown. This study investigated a wide range of TBPs circulating among ticks and grazing ruminants in the natural foci of Anatolia, Turkey. Tick specimens (n = 1815) were collected from cattle, sheep, and goats in three ecologically distinct areas (wooded, transitional, and semi-arid zones) of Anatolia and identified by species: Dermacentor marginatus, Dermacentor reticulatus, Hyalomma anatolicum, Hyalomma excavatum, Hyalomma marginatum, Hyalomma scupense, Haemaphysalis inermis, Haemaphysalis parva, Haemaphysalis punctata, Haemaphysalis sulcata, Ixodes ricinus, Rhipicephalus bursa, and Rhipicephalus turanicus. PCR-sequencing analyses revealed TBPs of great diversity, with 32 different agents identified in the ticks: six Babesia spp. (Babesia occultans, Babesia crassa, Babesia microti, Babesia rossi, Babesia sp. tavsan1, and Babesia sp. Ucbas); four Theileria spp., including one putative novel species (Theileria annulata, Theileria orientalis, Theileria ovis, and Theileria sp.); one Hepatozoon sp.; four Anaplasma spp., including one novel genotype (Anaplasma phagocytophilum, Anaplasma marginale, Anaplasma ovis, and Anaplasma sp.); six unnamed Ehrlichia spp. genotypes; Neoehrlichia mikurensis; nine spotted fever group rickettsiae, including one putative novel species (Rickettsia aeschlimannii, Rickettsia slovaca, Rickettsia hoogstraalii, Rickettsia monacensis with strain IRS3, Rickettsia mongolitimonae, Rickettsia raoultii, Candidatus Rickettsia goldwasserii, Candidatus Rickettsia barbariae, and Rickettsia sp.); and Borrelia valaisiana. Detailed phylogenetic analyses showed that some of the detected pathogens represent more than one haplotype, potentially relating to the tick species or the host. Additionally, the presence of Neoehrlichia mikurensis, an emerging pathogen for humans, was reported for the first time in Turkey, expanding its geographical distribution. Consequently, this study describes some previously unknown tick-borne protozoan and bacterial species/genotypes and provides informative epidemiological data on TBPs, which are related to animal and human health, serving the one health concept.     

Spatial distribution and molecular epidemiology of hemotropic Mycoplasma spp. and Mycoplasma haemocanis infection in dogs from Rio de Janeiro,Brazil

This cross-sectional study aims to investigate the epidemiology and spatial distribution of hemotropic Mycoplasma spp. and Mycoplasma haemocanis in dogs from Rio de Janeiro, Brazil. Blood samples were collected at random from 437 household dogs. An epidemiological questionnaire was completed concerning the host characteristics as well as the environments in which they lived. A positivity frequency of 17.84% (78/437) was found for Mycoplasma spp. and 2% (9/437) for M. haemocanis in Rio de Janeiro, Brazil, through molecular detection based on the 16S rRNA sequence. According to the present study, dogs that live in households with the presence of rodents (odds ratio [OR] = 9.93; p-value = 0.02; confidence interval [CI]: 1.34–73.66) and wild animals (OR = 1.91; p-value = 0.03; CI: 1.06–3.42) are more likely to be infected with Mycoplasma spp.. Also, dogs with tick infestation (OR = 6.47; p-value = 0.007; CI: 1.63–25.60) have more chances to become infected with M. haemocanis. The spatial analysis disclosed a positive correlation between the Mycoplasma presence and tick infestation (global Moran index = 0.82; pseudo-p-value =0.001). The epidemiological findings support the hypothesis of Rhipicephalus sanguineus s.l. as the vector of M. haemocanis in the studied region and provide insightful information to prevent the Mycoplasma spp. infection in dogs from Rio de Janeiro     

Ticks on humans in an Atlantic rainforest preserved ecosystem in Brazil: Species,life stages,attachment sites,and temporal pattern of infestation

We herein describe exposure and tick attachment to researchers and field staff within the greatest preserved inland Atlantic rainforest, located in Brazil, over a non-consecutive period of five years. Overall, 433 ticks from five species were collected, Amblyomma coelebs (n = 281), Amblyomma brasiliense (n = 79), Amblyomma incisum (n = 43), Amblyomma ovale (n = 4), Haemaphysalis juxtakochi (n = 4). Clusters of larvae belonged to the genus Amblyomma (n = 21) and Haemaphysalis (n = 1). Both Haemaphysalis and Amblyomma species were observed crawling on humans but only ticks from the latter genus were found attached. Most recovered ticks (59%) were found attached and, whereas A. brasiliense was the main host-seeking tick species in the forest, A. coelebs nymphs were the ones that overwhelmingly attached to humans (70% of all attachments). At the same time only 0.4% of human bites were of A. ovale, the Rickettsia parkeri strain Atlantic rainforest vector tick in Brazil. Tick attachment sites were recorded for 132 ticks and lower/upper limbs and the trunk were more parasitized than the head/neck. Tick bites were recorded throughout the year; while larvae did not show an evident seasonal pattern, nymphs attached to humans mainly in autumn and winter and the few adult bites were recorded in spring. Our results highlighted A. coelebs nymphs as major human-biters and evidenced the necessity of studies that discern human tick bites that occur after exposure to host-seeking ticks from those that occur after tick displacement from hosts that carry ticks to human dwellings.     

DNA barcoding of hard ticks (Ixodidae), notes on distribution of vector species and new faunal record for Croatia

Molecular methods are increasingly being utilized for accurate identification of ticks (Acari: Ixodidae), especially in cases of morphologically highly similar species. In this study, we performed molecular research of the tick fauna in Croatia using DNA barcoding method. Ticks were sampled in three biogeographical regions and thirteen species were recorded: Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna, Haemaphysalis inermis, Haemaphysalis punctata, Hyalomma marginatum, Ixodes frontalis, Ixodes hexagonus, Ixodes kaiseri, Ixodes ricinus, Rhipicephalus bursa, Rhipicephalus sanguineus s.l. and Rhipicephalus turanicus. Ixodes kaiseri is for the first time recorded in the fauna of Croatia. Of the thirteen hard tick species analyzed in this study, pathogens from different groups (bacteria, protozoa and viruses) have been detected in eight species in Croatia so far. For the important vector species R. sanguineus s.s., new distributional data for Croatia are given. The standard COI barcoding region was amplified, and the sequences were analyzed by species delimitation methods together with the sequences of conspecific and congeneric species from the public BOLD database. Our specimens of H. punctata represent a new, genetically distinct MOTU. A brief overview of the available public DNA barcoding data for Ixodidae is presented, highlighting the need for an integrative approach for the clarification of the taxonomic status of problematic Ixodid taxa. The results provide a basis for the establishment of a molecular data platform for the Ixodidae of the Croatian fauna.     

Tick species infesting cattle in the central region of Burkina Faso: Presence of Rhipicephalus microplus less than ten years after its first identification in the Southwest part of the country

Ticks are among the most important vectors for medical and veterinary importance in African countries, representing thus an obstacle for development and improvement of livestock production. The central part of Burkina Faso is an arid region which has a low diversity of tick species and in which Rhipicephalus microplus has been absent. This study aimed to examine ticks infesting cattle within this region, focusing on the peripheral area of Ouagadougou. Tick sampling was undertaken monthly on 30 selected cattle in the state breeding station of Loumbila, from June 2017 to February 2018. Morphological identification was carried out based on previous established keys and catalogue. A total of 1,076 ticks belonging to four genera and seven species were collected. Amblyomma variegatum (50.5%) was the most abundant species followed by Hyalomma rufipes (27.4%), Hyalomma truncatum (13.7%), Rhipicephalus decoloratus (4.5%), Hyalomma impressum (2.4%), Rhipicephalus microplus (1.5%), and Rhipicephalus sanguineus sensu lato (0.1%). The results suggested a decrease of A. variegatum and Hyalomma spp. load compared to data collected in 1996 from the same study area.Presence of R. microplus and R. decoloratus has been highlighted in the studied area for the first time. This finding highlights the relevance of regular investigations on tick species infesting livestock utilizing collaboration with different stakeholders.