Eco-epidemiology of Borrelia miyamotoi and Lyme borreliosis spirochetes in a popular hunting and recreational forest area in Hungary

Toxoplasma gondii in small mammals in Romania: the influence of host, season and sampling location

BACKGROUND

Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and insectivores play an important role in the epidemiology of T. gondii and may serve as a source of infection for both, domestic and wild definitive felid hosts. Factors influencing the occurrence of T. gondii in wild small mammals are unknown, despite the fact that many intermediate host species are identified. We have used small mammals (Rodentia and Lipotyphla) captured over two years in various habitats, both in urbanised and in natural landscapes. We assessed the importance of land-use, season and host ecology on T. gondii infection.

RESULTS

We examined 471 individuals belonging to 20 small mammal species, collected at 63 locations spread over wide altitude, habitat and land-use ranges from Romania. Heart tissue samples were individually analysed by PCR targeting the 529 bp repetitive DNA fragment of T. gondii. The overall prevalence of infection was 7.3%, with nine species of rodents and two species of shrews being found to carry T. gondii DNA. Five species showed high frequency of infection, with the highest prevalence found in Myodes glareolus (35.5%), followed by Spermophilus citellus (33.3%), Sorex minutus (23.1%), S. araneus (21.7%) and Micromys minutus (11.1%). Adults seemed more often infected than young, however when controlling for season, the difference was not significant, as in spring both adults and young showed higher infection rates, but more adults were sampled. Contrary to our expectations, urban/rural areas (with their implicit high density of domestic feline presence) had no effect on infection prevalence. In addition, neither habitat, nor land-use at sampling sites was important as only geographical location and host species were contributing factors to the infection risk.

CONCLUSIONS

High prevalence of T. gondii infection showed a highly localised, patchy occurrence, with long living and higher mobility host species being the most common carriers, especially during autumn.

Prevalence of Borrelia, Neoehrlichia mikurensis and Babesia in ticks collected from vegetation in eastern Poland

In Poland, tick-borne diseases constitute the majority of diseases related to exposure to biological agents with a predominance of Lyme borreliosis; therefore, research on ticks as a reservoir of various pathogens remains crucial in the epidemiology of human diseases after tick bites. This study aimed to identify the occurrence of Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Neoehrlichia mikurensis, and Babesia spp. in ticks collected from vegetation in eastern Poland. Additionally, the prevalence of co-infections in the adult Ixodes ricinus ticks was determined. Among I. ricinus ticks the predominantly detected pathogen was B. burgdorferi s.l. (23%) with B. burgdorferi sensu stricto as the most frequently identified species, followed by B. garinii. In 2013, the double or triple infections of B. burgdorferi s.s., B. afzelii, and B. garinii species did not exceed 9% in adult ticks, whereas in 2016, the prevalence of mixed infections reached 29%. The prevalence of N. mikurensis and B. miyamotoi in I. ricinus was determined at the same level of 2.8%. Four Babesia species were identified in the examined I. ricinus population: B. microti (1.5%), B. venatorum (1.2%), B. divergens (0.2%), and B. capreoli (0.1%). Co-infections were detected in 10.1% of all infected ticks with the highest prevalence of co-infections with B. burgdorferi s.l. and Babesia species. The changes in the prevalence and the distribution of particular pathogens within tick populations indicate the need for monitoring the current situation related to tick-borne pathogens from the aspect of risk to human health.

Exposure of dogs and cats to Borrelia miyamotoi infected Ixodes ricinus ticks in urban areas of the city of Poznań, west-central Poland

Borrelia miyamotoi is an emerging human pathogen that causes a relapsing fever-like disease named B. miyamotoi disease. The bacterium belongs to the relapsing fever borreliae, and similar to spirochetes of the Borrelia burgdorferi sensu lato group, it is transmitted only by hard ticks of the Ixodes ricinus complex. To date, B. miyamotoi has not been demonstrated to cause illness in dogs or cats, and is poorly documented in veterinary medicine. The aim of this study was to determine the B. miyamotoi presence in (i) host-seeking ticks and (ii) engorged Ixodes sp. ticks collected from dogs and cats during their inspection in veterinary clinics of the city of Poznań, west-central Poland. Host-seeking ticks were sampled in dog walking areas localized in urban forested recreational sites of the city. In this study, 1,059 host-seeking and 837 engorged I. ricinus ticks collected from 680 tick-infested animals (567 dogs and 113 cats) were screened. Additionally, 31 I. hexagonus ticks (one larva, 13 nymphs, and 17 females) were collected from three cats; one larva and one nymph were collected from two dogs; and one dog was infested with a single Dermacentor reticulatus female. Borrelia DNA was identified by the amplification and sequencing of the V4 hypervariable region of the 16S rRNA gene and flaB gene fragments. DNA of B. miyamotoi was detected in 22 (2.1%) of the host-seeking ticks (in all developmental tick stages and in all study areas). In addition, the engorged I. ricinus ticks exhibited a similar B. miyamotoi presence (1.8%). Fifteen I. ricinus ticks collected from animals tested positive for the presence of B. miyamotoi DNA, and the DNA of B. miyamotoi was observed in three (9.1%; one female and two nymphs) I. hexagonus ticks. The single D. reticulatus female collected from a dog tested PCR-negative for the bacterium. The results of this study demonstrated the establishment and broad presence of the bacterium in tick populations from different urban ecosystems of the city of Poznań. The lack of difference in the mean infection presence of animal-derived and host-seeking I. ricinus ticks suggests that the systematic surveillance of pets may be useful for the evaluation of human exposure to B. miyamotoi infected ticks in urban areas. Additional studies are required to further elucidate the role of domestic and wild carnivores in the epidemiology of B. miyamotoi, which remains unknown.

Borrelia miyamotoi: A Comprehensive Review

Borrelia miyamotoi is an emerging tick-borne pathogen in the Northern Hemisphere and is the causative agent of Borrelia miyamotoi disease (BMD). Borrelia miyamotoi is vectored by the same hard-bodied ticks as Lyme disease Borrelia, yet phylogenetically groups with relapsing fever Borrelia, and thus, has been uniquely labeled a hard tick-borne relapsing fever Borrelia. Burgeoning research has uncovered new aspects of B. miyamotoi in human patients, nature, and the lab. Of particular interest are novel findings on disease pathology, prevalence, diagnostic methods, ecological maintenance, transmission, and genetic characteristics. Herein, we review recent literature on B. miyamotoi, discuss how findings adapt to current Borrelia doctrines, and briefly consider what remains unknown about B. miyamotoi.

Borrelia miyamotoi a neglected tick-borne relapsing fever spirochete in Thailand

Borrelia miyamotoi is a relapsing fever spirochete that shares the same vector as Lyme disease causing Borrelia. This epidemiological study of B. miyamotoi was conducted in rodent reservoirs, tick vectors and human populations simultaneously. A total of 640 rodents and 43 ticks were collected from Phop Phra district, Tak province, Thailand. The prevalence rate for all Borrelia species was 2.3% and for B. miyamotoi was 1.1% in the rodent population, while the prevalence rate was quite high in ticks collected from rodents with an infection rate of 14.5% (95% CI: 6.3-27.6%). Borrelia miyamotoi was detected in Ixodes granulatus collected from Mus caroli and Berylmys bowersi, and was also detected in several rodent species (Bandicota indica, Mus spp., and Leopoldamys sabanus) that live in a cultivated land, increasing the risk of human exposure. Phylogenetic analysis revealed that the B. miyamotoi isolates detected in rodents and I. granulatus ticks in this study were similar to isolates detected in European countries. Further investigation was conducted to determine the serological reactivity to B. miyamotoi in human samples received from Phop Phra hospital, Tak province and in rodents captured from Phop Phra district using an in-house, direct enzyme-linked immunosorbent assay (ELISA) assay with B. miyamotoi recombinant glycerophosphodiester-phosphodiesterase (rGlpQ) protein as coated antigen. The results showed that 17.9% (15/84) of human patients and 9.0% (41/456) of captured rodents had serological reactivity to B. miyamotoi rGlpQ protein in the study area. While a low level of IgG antibody titers (100-200) was observed in the majority of seroreactive samples, higher titers (400-1,600) were also detected in both humans and rodents. This study provides the first evidence of B. miyamotoi exposure in human and rodent populations in Thailand and the possible roles of local rodent species and Ixodes granulatus tick in its enzootic transmission cycle in nature.

The first detection of relapsing fever spirochete Borrelia miyamotoi in Ixodes ricinus ticks from the northeast Czech Republic

Borrelia miyamotoi, a relapsing fever spirochete, is considered a human pathogen. Knowledge of this borrelia is currently limited. Data about its potential impact on public health, circulation in nature, or its occurrence in natural environments are insufficient. For our study, a total of 505 questing Ixodes ricinus ticks (337 nymphs, 85 females and 83 males) from Hradec Králové Region in the Czech Republic were collected. Additionally, 160 winged Lipoptena deer keds from Hradec Králové Region, from Pardubice Region, Czech Republic, and from one location in western Slovakia were collected. The presence of B. miyamotoi in ticks and deer keds was determined using polymerase chain reaction (PCR) targeting a gene encoding glycerophosphodiester phosphodiesterase (glpQ), antigenic protein specific to the relapsing fever spirochetes. Borrelia miyamotoi was identified in six nymphs and four females of I. ricinus ticks. The overall prevalence was 2%. None of the examined Lipoptena specimens were found to be infected. Although no human case of infection with B. miyamotoi has been reported in the Czech Republic yet, this spirochete is widespread in ticks, and therefore the risk of human infection exists.

Borrelia burgdorferi and Borrelia miyamotoi in Atlantic Canadian wildlife

Borrelia burgdorferi and Borrelia miyamotoi are tick-vectored zoonotic pathogens maintained in wildlife species. Tick populations are establishing in new areas globally in response to climate change and other factors. New Brunswick is a Canadian maritime province at the advancing front of tick population establishment and has seen increasing numbers of ticks carrying B. burgdorferi, and more recently B. miyamotoi. Further, it is part of a region of Atlantic Canada with wildlife species composition differing from much of continental North America and little information exists as to the presence and frequency of infection of Borrelia spp. in wildlife in this region. We used a citizen science approach to collect a wide range of animals including migratory birds, medium-sized mammals, and small mammals. In total we tested 339 animals representing 20 species for the presence of B. burgdorferi and B. miyamotoi. We have developed new nested PCR primers and a protocol with excellent specificity for detecting both of these Borrelia species, both single and double infections, in tissues and organs of various wildlife species. The positive animals were primarily small non-migratory mammals, approximately twice as many were infected with B. burgdorferi than B. miyamotoi and one animal was found infected with both. In addition to established reservoir species, the jumping mouse (Napaeozapus insignis) was found frequently infected; this species had the highest infection prevalence for both B. burgdorferi and B. miyamotoi and has not previously been identified as an important carrier for either Borrelia species. Comprehensive testing of tissues found that all instances of B. burgdorferi infection were limited to one tissue within the host, whereas two of the five B. miyamotoi infections were diffuse and found in multiple systems. In the one coinfected specimen, two fetuses were also recovered and found infected with B. miyamotoi. This presumptive transplacental transmission suggests that vertical transmission in mammals is possible. This finding implies that B. miyamotoi could rapidly spread into wildlife populations, as well as having potential human health implications.

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.

Environmental determinants of the occurrence and activity of Ixodes ricinus ticks and the prevalence of tick-borne diseases in eastern Poland

Ixodes ricinus is the most widely distributed tick species in Europe. Mainly deciduous and mixed forests, pastures, and urban parks are habitats preferred by this species. I. ricinus ticks are also one of the most important reservoirs and vectors of human and animal infectious diseases on the continent. Borrelia burgdorferi s.l. spirochetes causing Lyme borreliosis (LB) in humans and tick borne encephalitis virus (TBEV), which is a causative agent of tick-borne encephalitis (TBE), are pathogens with the highest medical importance transmitted by this species. Investigations of the environmental determinants of the occurrence and activity of I. ricinus are crucial for elucidation of the environmental background of tick-borne diseases. In eastern Poland, I. ricinus is a common species with peak activity recorded in May in the entire region. During this period, 49 females, 32 males, and 55 I. ricinus nymphs were collected from an area of 900 m². The results of the present study show that the occurrence and seasonal activity of this tick species are mainly influenced by microhabitat conditions, and saturation deficit has a significant effect on the activity of the species. Eastern Poland is characterized by a high incidence of LB and TBE. We have shown a correlation between the forest cover and the number of reported cases of tick-borne diseases.

Borrelia miyamotoi infection in Apodemus spp. mice populating an urban habitat (Warsaw, Poland)

The two of three species of city-inhabiting (Warsaw, Poland) Apodemus spp. mice were showed to be infected with Borrelia miyamotoi, spirochete bacterium considered to be a tick-borne relapsing fever (TBRF) disease causative agent. The pathogen infection was ascertained based on bacterium DNA presence in a blood (obtained from the lateral tail vein) of the mice, using the nested polymerase chain reaction (PCR) technique. The B. miyamotoi carriers populated not only green spaces situated in the suburban areas but also recreational parks and lawns in the city centre proper. Moreover, we found no significant differences in the infection rate depending on mouse species. The total prevalence of infection at the level of 5.6% suggests the potential role of urban-settled rodents in the spreading of the tick-borne zoonosis, which pose high risk to public health.

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First confirmation of Borrelia miyamotoi infection in urban rodents in Poland.

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The pathogen was found to infect city-inhabiting mice with a total prevalence of 5.6%.

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Degree of human pressure within habitat did not affect rodents' infection rate.

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Tick-borne zoonosis spread by mice could pose potential high risk to public health.

Borrelia miyamotoi-An Emerging Human Tick-Borne Pathogen in Europe

Borrelia miyamotoi is classified as a relapsing fever spirochete. Although B. miyamotoi is genetically and ecologically distinct from Borrelia burgdorferi sensu lato, both microorganisms are transmitted by the same Ixodes tick species. B. miyamotoi was detected in I. persulcatus ticks in 1994 in Japan. A phylogenetic analysis based on selected sequences of B. miyamotoi genome revealed genetic differences between isolates from Asia, North America, and Europe, which are clearly separated into three genotypes. Symptomatic human cases of Borrelia miyamotoi disease (BMD) were first reported in 2011 in Russia and then in North America, Europe, and Asia. The most common clinical manifestation of BMD is fever with flu-like symptoms. Several differences in rare symptoms (thrombocytopenia, monocytosis, cerebrospinal fluid pleocytosis, or symptoms related to the central nervous system) have been noted among cases caused by Asian, European, and American types of B. miyamotoi. BMD should be considered in the diagnosis of patients after tick bites, particularly with meningoencephalitis, without anti-Borrelia antibodies in the cerebrospinal fluid. This review describes the biology, ecology, and potential of B. miyamotoi as a tick-borne pathogen of public health concern, with particular emphasis on Europe.

The Unexpected Holiday Souvenir: The Public Health Risk to UK Travellers from Ticks Acquired Overseas

Overseas travel to regions where ticks are found can increase travellers' exposure to ticks and pathogens that may be unfamiliar to medical professionals in their home countries. Previous studies have detailed non-native tick species removed from recently returned travellers, occasionally leading to travel-associated human cases of exotic tick-borne disease. There are 20 species of tick endemic to the UK, yet UK travellers can be exposed to many other non-native species whilst overseas. Here, we report ticks received by Public Health England's Tick Surveillance Scheme from humans with recent travel history between January 2006 and December 2018. Altogether, 16 tick species were received from people who had recently travelled overseas. Confirmed imports (acquired outside of the UK) were received from people who recently travelled to 22 countries. Possible imports (acquired abroad or within the UK) were received from people who had recently travelled to eight European countries. Species-specific literature reviews highlighted nine of the sixteen tick species are known to vector at least one tick-borne pathogen to humans in the country of acquisition, suggesting travellers exposed to ticks may be at risk of being bitten by a species that is a known vector, with implications for novel tick-borne disease transmission to travellers.

Ticks, fleas and rodent-hosts analyzed for the presence of Borrelia miyamotoi in Slovakia: the first record of Borrelia miyamotoi in a Haemaphysalis inermis tick

In Slovakia, little knowledge is available on the occurrence, hosts and vectors of Borrelia miyamotoi of the relapsing fever group. In the current study, 2160 questing and rodent-attached ticks of six species (Ixodes ricinus, Ixodes trianguliceps, Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna and Haemaphysalis inermis), 279 fleas belonging to 9 species (Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus assimilis, Megabothris turbidus, Amalareus penicilliger, Hystrichopsylla orientalis, Ctenophthalmus uncinatus, Doratopsylla dasycnema and Nosopsyllus fasciatus) and skin biopsies from 245 small mammals belonging to eight species (Apodemus agrarius, Apodemus flavicollis, Apodemus uralensis, Myodes glareolus, Crocidura leucodon, Micromys minutus, Microtus arvalis, Microtus subterraneus) were screened for the presence of B. miyamotoi DNA. The overall prevalence of B. miyamotoi found in questing and rodent-attached ticks was 1.8% (23 positive/1260 examined) and 3.4% (31 positive/900 examined), respectively. Borrelia miyamotoi was detected in questing I. ricinus, rodent-attached I. ricinus and H. inermis ticks, and in one male of the common vole (M. arvalis) in different habitats (mainly rural) in eastern Slovakia. However, B. miyamotoi was not found in any of the tested fleas. Our findings indicate that rural habitats with different species of tick vectors and hosts are appropriate for the occurrence of B. miyamotoi.

Multiple Tick-Borne Pathogens in Ixodes ricinus Ticks Collected from Humans in Romania

Ticks are medically important vectors of infectious diseases that are able to transmit pathogens to humans and animals. Tick-borne diseases represent a major health concern, posing an increasing risk to the public health during the last century and affecting millions of people. The aim of the current study was to provide epidemiological data regarding the presence of certain tick-borne pathogens in ticks feeding on humans in Romania. Overall, 522 Ixodes ricinus ticks collected from humans were screened for six pathogens: Borrelia spp., Neoehrlichia mikurensis, Babesia spp., Coxiella spp., Bartonella spp., and Francisella tularensis. Ticks attached to humans were collected between 2013-2015 in Cluj County, Romania. Conventional, nested and quantitative PCR were used to detect specific genetic sequences of each pathogen. For identifying the infectious agents, positive samples were sequenced. The infection prevalence was 21.07% from which 8.18% were mixed infections. The detected agents were Borrelia spp., N. mikurensis and Babesia spp. The present data reveal the endemic occurrence of potentially zoonotic pathogens in Romania. Revealing the current distribution of tick-borne pathogens in ticks collected from humans may provide new insights in understanding the complex ecology of tick-borne diseases and enlightens current knowledge about the infection prevalence at local, regional and national levels.

Ticks on the Channel Islands and implications for public health

The Channel Islands are British Crown dependencies located in the English Channel to the west of the Normandy coast in northern France. Whilst there have been studies investigating tick occurrence and distribution in different habitats on the mainland of the UK and in France, the Channel Islands have been relatively understudied. As such, little is known about whether the sheep tick, Ixodes ricinus, is present, and whether there is a potential risk of Lyme borreliosis on the Channel Islands. To ascertain the presence of I. ricinus on the three largest islands in the archipelago: Jersey, Guernsey and Alderney, surveys of ticks questing in the vegetation and ticks feeding on hosts were undertaken during April and May 2016. Across all three islands, the highest numbers of ticks were found in woodland habitats. Ixodes ricinus was the predominant questing tick species found on Jersey, and Ixodes ventalloi the most common questing tick species on Alderney and Guernsey, with little or no evidence of questing I. ricinus on either island. During field studies on small mammals, I. ricinus was the predominant tick species feeding on Jersey bank voles (Myodes glareolus caesarius), with Ixodes hexagonus the most common species infesting hedgehogs on Guernsey. We propose that the greater diversity of small mammals on Jersey may be important in supporting immature stages of I. ricinus, in contrast to Guernsey and Alderney. Morphological identification of tick species was confirmed by PCR sequencing based on amplification of the cytochrome c oxidase subunit one (cox1) gene (COI DNA barcoding). To date, there have been few records of human tick bites in the Channel Islands, suggesting that the current risk from tick-borne disease may be low, but continued reporting of any human tick bites, along with reporting of cases of Lyme borreliosis will be important for continued assessment of the impact of tick-borne diseases in the Channel Islands.

Borrelia spp. in small mammals in Romania

BACKGROUND

Small mammals play an important role in the life-cycle of ticks and are reservoirs for several zoonotic pathogens. The aim of this study was to provide epidemiological data regarding the presence of Borrelia spp. in tissues of small mammals from Romania.

METHODS

We examined 401 individuals belonging to 11 small mammal species collected in Romania. Collections cover the largest effort to survey these reservoirs in the country. Tissue samples were analyzed by multiplex qPCR targeting the ospA gene of Borrelia burgdorferi (s.l.) and a part of the flaB gene of B. miyamotoi. Positive samples were further analysed by conventional PCR and sequenced.

RESULTS

The overall prevalence of infection with Borrelia spp. in small mammal tissues was 4.9%. The most commonly detected species were B. afzelii, followed by B. garinii/B. bavariensis, B. miyamotoi and B. burgdorferi (s.s.). To our knowledge, we report for the first time the detection of Borrelia spp. in Crocidura leucodon and C. suaveolens, and B. miyamotoi in the liver of Myodes glareolus.

CONCLUSIONS

To our knowledge, our study evaluates for the first time the occurrence of Borrelia spp. in small mammals in Romania, contributing to a better knowledge of the distribution of these bacteria. This survey upgrades previous data on the spatial distribution of the pathogens and reveals the importance of animal surveillance regarding Lyme borreliosis and relapsing fever caused by B. miyamotoi.

Questing Ixodes ricinus ticks (Acari, Ixodidae) as a vector of Borrelia burgdorferi sensu lato and Borrelia miyamotoi in an urban area of north-eastern Poland

Green areas located within large cities, as natural ecotypes, are a convenient habitat for ticks and their use as recreational areas is associated with the potential risk of acquiring tick-borne diseases. This study estimated the I. ricinus tick density, prevalence of infection with Borrelia species and the diversity of these bacteria in a green urban area (Olsztyn) of north-eastern Poland, an endemic region of tick-borne diseases. The ticks were collected during spring and autumn of 2015, at sites differing in the degree of human pressure and habitat. Borrelia species detection, typing and a molecular phylogenetic analysis were carried out based on the sequenced flaB gene. The overall mean abundance of I. ricinus was 2.0 ± 1.55 ticks per 100 m². The density of I. ricinus did not vary significantly between sites. According to semi-qualitative tick abundance categories, the collection sites were classified as 'very low' and 'low' tick abundance category. The overall infection rate of I. ricinus with Borrelia spirochaetes was 27.4%. The infection rate of adult ticks (42.0%) was three times higher than with nymphs (14.3%). Based on the restriction patterns and sequencing, B. afzelii (93.1%; 27/29), B. valaisiana 3.5% (1/29) and B. miyamotoi (3.5%; 1/29), related to the relapsing fever (RF) spirochaetes, were detected. No co-infections were found. Borrelia miyamotoi, detected for the first time in ticks in the north-eastern urban areas of Poland, was identical to isolates described as European-type. The Borrelia spirochaete infection rate of I. ricinus ticks in an urban area indicated a high risk of LB. Physicians should also be aware of B. miyamotoi infections among patients with a history of tick-bites in north-eastern Poland.

Simultaneous Occurrence of Borrelia miyamotoi, Borrelia burgdorferi Sensu Lato, Anaplasma phagocytophilum and Rickettsia helvetica in Ixodes ricinus Ticks in Urban Foci in Bratislava, Slovakia

BACKGROUND

Questing Ixodes ricinus ticks were collected in two urban parks (Železná studienka and Horský park) of the capital city of Slovakia, Bratislava, during two consecutive years in 2011 and 2012. A total of 932 ticks were analyzed for the presence of tick-borne agents: B. miyamotoi, B. burgdorferi s.l., A. phagocytophilum and R. helvetica.

RESULTS

PCR analysis confirmed the presence of all pathogens at both localities. The overall infection prevalence of B. miyamotoi, B. burgdorferi s.l., A. phagocytophilum and R. helvetica was 0.75, 13.2, 5.6 and 8.9%, respectively. B. burgdorferi s.l. positive samples were represented by six genospecies. The most frequent one was B. afzelii followed by B. garinii and B. valaisiana.

CONCLUSION

Our study confirms the presence of I. ricinus ticks and at least nine tick-borne bacterial agents in city forest parks, which are used for recreational purposes. Ordination analysis revealed significant differences in the composition of pathogens with respect to study site location, time of season and ambient temperature, despite the fact that both sites are located relatively close to one another within the city.

Using volunteered observations to map human exposure to ticks

Lyme borreliosis (LB) is the most prevalent tick-borne disease in Europe and its incidence has steadily increased over the last two decades. In the Netherlands alone, more than 20,000 citizens are affected by LB each year. Because of this, two Dutch citizen science projects were started to monitor tick bites. Both projects have collected nearly 50,000 geo-located tick bite reports over the period 2006–2016. The number of tick bite reports per area unit is a proxy of tick bite risk. This risk can also be modelled as the result of the interaction of hazard (e.g. tick activity) and human exposure (e.g. outdoor recreational activities). Multiple studies have focused on quantifying tick hazard. However, quantifying human exposure is a harder task. In this work, we make a first step to map human exposure to ticks by combining tick bite reports with a tick hazard model. Our results show human exposure to tick bites in all forested areas of the Netherlands. This information could facilitate the cooperation between public health specialists and forest managers to create better mitigation campaigns for tick-borne diseases, and it could also support the design of improved plans for ecosystem management.

Road-killed mammals provide insight into tick-borne bacterial pathogen communities within urban habitats

Small- and medium-sized mammals play an important role in the life cycle of tick-borne pathogens in urban habitats. Our aim was to apply the general protocol, DAMA (documentation-assessment-monitoring-action), which is an integrated proposal to build a proactive capacity to understand, anticipate, and respond to the outcomes of accelerating environmental change. Here we tested whether road-killed carcasses in urban areas are useful sources of tissue and parasite samples to investigate these species' contribution to the epidemiology of vector-borne diseases. We collected 29 road-killed and 6 carcasses with different causes of mortality (23 northern white-breasted hedgehogs and 12 from seven other mammal species) mainly from Budapest, Hungary. We used quantitative and conventional PCRs to determine pathogens in 90 collected tissues (52 from hedgehogs; 38 from other species) and 417 ticks that were only found on hedgehogs. Tissue samples revealed a wide range of bacteria including human zoonotic pathogens identified as Anaplasma phagocytophilum ecotype I, Borrelia afzelii, B. spielmanii, Borrelia miyamotoi, Rickettsia helvetica, and Bartonella species. Among the 23 collected hedgehog carcasses, 17 (74%) were infected with A. phagocytophilum, 6 (26%) with Borrelia burgdorferi s.l., 12 (52%) with R. helvetica, and 15 (65%) with Rickettsia sp. Furthermore, we report the first detection of Rickettsia sp. infection in European moles and lesser weasel and R. helvetica in stone marten. Through sequencing B. afzelii, R. helvetica, R. monacensis and A. phagocytophilum ecotype I were identified in the ticks removed from the carcasses. We showed that road-killed urban mammal species are exposed to multiple tick-borne pathogens but further studies have to clarify whether they, in fact, also have a role in their maintenance and spread. Our study also demonstrates that roadkill can be used in the risk assessment of potential human infection and in the implementation of the DAMA protocol.

Detection of tick-borne pathogens in ticks from dogs and cats in different European countries

Ticks are known to transmit pathogens which threaten the health and welfare of companion animals and man globally. In the present study, mainly adult ticks were collected from dogs and cats presented at their local veterinary practice in Hungary, France, Italy, Belgium (dogs only) and Germany (cats only), and identified based on tick morphology. If more than one tick was collected from a host animal, ticks were pooled by tick species for DNA extraction and subsequent PCR examination for the presence of tick-borne pathogens. Out of 448 tick samples, 247 (95 from dogs and 152 from cats) were Ixodes ricinus, 26 (12 from dogs and 14 from cats) were I. hexagonus, 59 (43 from dogs and 16 from cats) were Dermacentor reticulatus and 116 (74 from dogs and 42 from cats) were Rhipicephalus sanguineus sensu lato (s.l.). In 17% of the I. ricinus samples Anaplasma phagocytophilum was found. Borrelia spp. were mainly identified in I. ricinus collected from cats (18%) and to a lesser extent in dog-sourced ticks (1%), with Borrelia afzelii (n = 11), B. garinii (n = 7), B. valaisiana (n = 5), B. lusitaniae (n = 3) and B. burgdorferi sensu stricto (n = 3) being identified. One I. hexagonus sample collected from a cat in France tested positive for B. afzelii. Babesia canis was detected in 20% of the D. reticulatus samples, mainly from Hungary. Rhipicephalus sanguineus s.l. was found positive for Hepatozoon canis (3%), A. platys (5%) and three Rickettsia species (7%; R. massiliae; R. raoultii and R. rhipicephali). Furthermore, a total of 66 R. sanguineus s.l. ticks were subjected to molecular analysis and were identified as R. sanguineus sp. II-temperate lineage, with seven haplotypes recorded. Amongst them, the most prevalent sequence types were haplotype XIII (n = 24; 69%) and haplotype XIV (n = 16; 52%) in France and in Italy, respectively, found both in cats and dogs. Although differences related to both country and host, were observed, the results of this study indicate that cats and dogs are exposed to tick-borne pathogen infected ticks, which may represent a medical risk to these host animals.

Prevalence and Geographic Distribution of Borrelia miyamotoi in Host-Seeking Ixodes pacificus (Acari: Ixodidae) Nymphs in Mendocino County, California

Borrelia miyamotoi is an increasingly recognized human pathogen transmitted by Ixodes ticks in the Northern Hemisphere. In North America, infection prevalences of B. miyamotoi are characteristically low (<10%) in Ixodes scapularis (Say; Acari: Ixodidae) and Ixodes pacificus (Cooley & Kohls; Acari: Ixodidae), both of which readily bite humans. We tested 3,255 host-seeking I. pacificus nymphs collected in 2004 from 79 sites throughout Mendocino County in north-coastal California for presence of B. miyamotoi. The collection sites represented a variety of forest types ranging from hot, dry oak woodlands in the southeast, to coastal redwoods in the west, and Ponderosa pine and Douglas fir-dominated areas in the northern part of the county. We found that B. miyamotoi was geographically widespread, but infected I. pacificus nymphs infrequently (cumulative prevalence of 1.4%). Infection prevalence was not significantly associated with geographic region or woodland type, and neither density of host-seeking nymphs, nor infection with Borrelia burgdorferi sensu stricto was associated with B. miyamotoi infection status in individual ticks. Because B. burgdorferi prevalence at the same sites was previously associated with woodland type and nymphal density, our results suggest that despite sharing a common vector, the primary modes of enzootic maintenance for the two pathogens are likely different.

Relapsing Fevers: Neglected Tick-Borne Diseases

Relapsing fever still remains a neglected disease and little is known on its reservoir, tick vector and physiopathology in the vertebrate host. The disease occurs in temperate as well as tropical countries. Relapsing fever borreliae are spirochaetes, members of the Borreliaceae family which also contain Lyme disease spirochaetes. They are mainly transmitted by Ornithodoros soft ticks, but some species are vectored by ixodid ticks. Traditionally a Borrelia species is associated with a specific vector in a particular geographical area. However, new species are regularly described, and taxonomical uncertainties deserve further investigations to better understand Borrelia vector/host adaptation. The medical importance of Borrelia miyamotoi, transmitted by Ixodes spp., has recently spawned new interest in this bacterial group. In this review, recent data on tick-host-pathogen interactions for tick-borne relapsing fevers is presented, with special focus on B. miyamotoi.

Assessing bat droppings and predatory bird pellets for vector-borne bacteria: molecular evidence of bat-associated Neorickettsia sp. in Europe

In Europe, several species of bats, owls and kestrels exemplify highly urbanised, flying vertebrates, which may get close to humans or domestic animals. Bat droppings and bird pellets may have epidemiological, as well as diagnostic significance from the point of view of pathogens. In this work 221 bat faecal and 118 bird pellet samples were screened for a broad range of vector-borne bacteria using PCR-based methods. Rickettsia DNA was detected in 13 bat faecal DNA extracts, including the sequence of a rickettsial insect endosymbiont, a novel Rickettsia genotype and Rickettsia helvetica. Faecal samples of the pond bat (Myotis dasycneme) were positive for a Neorickettsia sp. and for haemoplasmas of the haemofelis group. In addition, two bird pellets (collected from a Long-eared Owl, Asio otus, and from a Common Kestrel, Falco tinnunculus) contained the DNA of a Rickettsia sp. and Anaplasma phagocytophilum, respectively. In both of these bird pellets the bones of Microtus arvalis were identified. All samples were negative for Borrelia burgdorferi s.l., Francisella tularensis, Coxiella burnetii and Chlamydiales. In conclusion, bats were shown to pass rickettsia and haemoplasma DNA in their faeces. Molecular evidence is provided for the presence of Neorickettsia sp. in bat faeces in Europe. In the evaluated regions bat faeces and owl/kestrel pellets do not appear to pose epidemiological risk from the point of view of F. tularensis, C. burnetii and Chlamydiales. Testing of bird pellets may provide an alternative approach to trapping for assessing the local occurrence of vector-borne bacteria in small mammals.

Prevalence of Borrelia miyamotoi and Borrelia burgdorferi sensu lato in questing ticks from a recreational coniferous forest of East Saxony, Germany

The hard tick Ixodes ricinus is the most important vector of tick-transmitted pathogens in Europe, frequently occurring in urban parks and greenbelts utilized for recreational activities. This species is the most common vector of the causative agents of Lyme borreliosis in Europe. Similarly, the species spreads Borrelia miyamotoi, causing a relapsing-fever like illness. A total of 1774 Ixodes ricinus (50 females, 68 males, 840 nymphs and 818 larvae) were collected with flagging between March and September 2014 in a coniferous forest patch in Niederkaina near the town of Bautzen in Saxony, Germany. To measure questing tick density a time-based density estimating method was utilized. From each month, a total of 100 adults and nymphal ticks and all larvae (pools of 10 individuals per tube/month) were selected for the molecular analyses. For simultaneous detection of B. burgdorferi s.l. and B. miyamotoi a duplex real-time PCR targeting the flaB locus was performed. Prevalence of B. burgdorferi s.l. was 9.4% (female: 6%, male: 2.9%, nymph: 12.2%, larva: 0%) and minimum prevalence of B. miyamotoi was 1.2% (female: 0%, male: 4.3%, nymph: 2.8%, larva: 0.1%) in the 714 samples with real-time polymerase chain reaction. A real-time PCR reaction was utilized first to target the histone-like protein gene (hbb) of B. burgdorferi s.l., a hemi-nested outer surface protein (ospA) gene conventional PCR was then performed followed by a restriction enzyme analysis to distinguish B. burgdorferi s.l. genospecies. Seven B. afzelii, one B. burgdorferi s.s., one B. bavariensis and four B. miyamotoi infections were confirmed. Prevalence of Lyme borreliosis spirochetes was significantly higher in nymphs than in adults (p<0.01, Fisher exact test) probably due to the diluting effect of the local roe deer population. Our data highlight the potential risk of human infection with the emerging pathogen B. miyamotoi within the study area.

Europe-Wide Meta-Analysis of Borrelia burgdorferi Sensu Lato Prevalence in Questing Ixodes ricinus Ticks

Lyme borreliosis is the most common zoonotic disease transmitted by ticks in Europe and North America. Despite having multiple tick vectors, the causative agent, Borrelia burgdorferisensu lato, is vectored mainly by Ixodes ricinus in Europe. In the present study, we aimed to review and summarize the existing data published from 2010 to 2016 concerning the prevalence of B. burgdorferi sensu lato spirochetes in questing I. ricinus ticks. The primary focus was to evaluate the infection rate of these bacteria in ticks, accounting for tick stage, adult tick gender, region, and detection method, as well as to investigate any changes in prevalence over time. The data obtained were compared to the findings of a previous metastudy. The literature search identified data from 23 countries, with 115,028 ticks, in total, inspected for infection with B. burgdorferi sensu lato We showed that the infection rate was significantly higher in adults than in nymphs and in females than in males. We found significant differences between European regions, with the highest infection rates in Central Europe. The most common genospecies were B. afzelii and B. garinii, despite a negative correlation of their prevalence rates. No statistically significant differences were found among the prevalence rates determined by conventional PCR, nested PCR, and real-time PCR.IMPORTANCEBorrelia burgdorferisensu lato is a pathogenic bacterium whose clinical manifestations are associated with Lyme borreliosis. This vector-borne disease is a major public health concern in Europe and North America and may lead to severe arthritic, cardiovascular, and neurological complications if left untreated. Although pathogen prevalence is considered an important predictor of infection risk, solitary isolated data have only limited value. Here we provide summarized information about the prevalence of B. burgdorferi sensu lato spirochetes among host-seeking Ixodes ricinus ticks, the principal tick vector of borreliae in Europe. We compare the new results with previously published data in order to evaluate any changing trends in tick infection.

Emerging Tick-Borne Bacterial Pathogens

A vast number of novel tick-related microorganisms and tick-borne disease agents have been identified in the past 20 years, and more are being described due to several factors, from the curiosity of clinicians faced with unusual clinical syndromes to new tools used by microbiologists and entomologists. Borrelioses, ehrlichioses, anaplasmosis, and tick-borne rickettsial diseases are some of the emerging diseases that have been described throughout the world in recent years. In this article, we focus on the bacterial agents and diseases that have been recognized in the past 3 years and refer to major recent reviews of other recognized infections.

Approaches for Reverse Line Blot-Based Detection of Microbial Pathogens in Ixodes ricinus Ticks Collected in Austria and Impact of the Chosen Method

Ticks transmit a large number of pathogens capable of causing human disease. In this study, the PCR-reverse line blot (RLB) method was used to screen for pathogens in a total of 554 Ixodes ricinus ticks collected from all provinces of Austria. These pathogens belong to the genera Borrelia, Rickettsiae, Anaplasma/Ehrlichia (including "Candidatus Neoehrlichia"), Babesia, and Coxiella The pathogens with the highest detected prevalence were spirochetes of the Borrelia burgdorferisensu lato complex, in 142 ticks (25.6%). Borrelia afzelii (80/142) was the most frequently detected species, followed by Borrelia burgdorferisensu stricto (38/142) and Borrelia valaisiana (36/142). Borrelia garinii/Borrelia bavariensis, Borrelia lusitaniae, and Borrelia spielmanii were found in 28 ticks, 5 ticks, and 1 tick, respectively. Rickettsia spp. were detected in 93 ticks (16.8%): R. helvetica (39/93), R. raoultii (38/93), R. monacensis (2/93), and R. slovaca (1/93). Thirteen Rickettsia samples remain uncharacterized. "Candidatus Neoehrlichia mikurensis," Babesia spp. (B. venatorum, B. divergens, B. microti), and Anaplasma phagocytophilum were found in 4.5%, 2.7%, and 0.7%, respectively. Coxiella burnetii was not detected. Multiple microorganisms were detected in 40 ticks (7.2%), and the cooccurrence of Babesia spp. and "Candidatus Neoehrlichia mikurensis" showed a significant positive correlation. We also compared different PCR-RLBs for detection of Borrelia burgdorferisensu lato and Rickettsia spp. and showed that different detection approaches provide highly diverse results, indicating that analysis of environmental samples remains challenging.IMPORTANCE This study determined the wide spectrum of tick-borne bacterial and protozoal pathogens that can be encountered in Austria. Surveillance of (putative) pathogenic microorganisms occurring in the environment is of medical importance, especially when those agents can be transmitted by ticks and cause disease. The observation of significant coinfections of certain microorganisms in field-collected ticks is an initial step to an improved understanding of microbial interactions in ticks. In addition, we show that variations in molecular detection methods, such as in primer pairs and target genes, can considerably influence the final results. For instance, detection of certain genospecies of borreliae may be better or worse by one method or the other, a fact of great importance for future screening studies.

Borrelia miyamotoi and Co-Infection with Borrelia afzelii in Ixodes ricinus Ticks and Rodents from Slovakia

Borrelia miyamotoi causes relapsing fever in humans. The occurrence of this spirochete has been reported in Ixodes ricinus and wildlife, but there are still gaps in the knowledge of its eco-epidemiology and public health impact. In the current study, questing I. ricinus (nymphs and adults) and skin biopsies from rodents captured in Slovakia were screened for the presence of B. miyamotoi and Borrelia burgdorferi s.l. DNA. The prevalence of B. miyamotoi and B. burgdorferi s.l. in questing ticks was 1.7 and 16.9%, respectively. B. miyamotoi was detected in Apodemus flavicollis (9.3%) and Myodes glareolus (4.4%). In contrast, B. burgdorferi s.l. was identified in 11.9% of rodents, with the highest prevalence in Microtus arvalis (68.4%) and a lower prevalence in Apodemus spp. (8.4%) and M. glareolus (12.4%). Borrelia afzelii was the prevailing genospecies infecting questing I. ricinus (37.9%) and rodents (72.2%). Co-infections of B. miyamotoi and B. burgdorferi s.l. were found in 24.1 and 9.3% of the questing ticks and rodents, respectively, whereas the proportion of ticks and rodents co-infected with B. miyamotoi and B. afzelii was 6.9 and 7.0%, respectively. The results suggest that B. miyamotoi and B. afzelii share amplifying hosts. The sequences of the B. miyamotoi glpQ gene fragment from our study showed a high degree of identity with sequences of the gene amplified from ticks and human patients in Europe. The results seem to suggest that humans in Slovakia are at risk of contracting tick-borne relapsing fever, and in some cases together with Lyme borreliosis.

Host Immune Evasion by Lyme and Relapsing Fever Borreliae: Findings to Lead Future Studies for Borrelia miyamotoi

The emerging pathogen, Borrelia miyamotoi, is a relapsing fever spirochete vectored by the same species of Ixodes ticks that carry the causative agents of Lyme disease in the US, Europe, and Asia. Symptoms caused by infection with B. miyamotoi are similar to a relapsing fever infection. However, B. miyamotoi has adapted to different vectors and reservoirs, which could result in unique physiology, including immune evasion mechanisms. Lyme Borrelia utilize a combination of Ixodes-produced inhibitors and native proteins [i.e., factor H-binding proteins (FHBPs)/complement regulator-acquiring surface proteins, p43, BBK32, BGA66, BGA71, CD59-like protein] to inhibit complement, while some relapsing fever spirochetes use C4b-binding protein and likely Ornithodoros-produced inhibitors. To evade the humoral response, Borrelia utilize antigenic variation of either outer surface proteins (Osps) and the Vmp-like sequences (Vls) system (Lyme borreliae) or variable membrane proteins (Vmps, relapsing fever borreliae). B. miyamotoi possesses putative FHBPs and antigenic variation of Vmps has been demonstrated. This review summarizes and compares the common mechanisms utilized by Lyme and relapsing fever spirochetes, as well as the current state of understanding immune evasion by B. miyamotoi.

Borrelia miyamotoi in vectors and hosts in The Netherlands

Ixodes ticks transmit Borrelia burgdorferi sensu lato (s.l.), the causative agent of Lyme borreliosis (LB). These tick species also transmit Borrelia miyamotoi, which was recently found to cause infections in humans. We were interested in the prevalence of B. miyamotoi infection in ticks and natural hosts in The Netherlands, and to what extent ticks are co-infected with B. burgdorferi. In addition, erythema migrans has been sporadically described in B. miyamotoi-infected patients, but these skin lesions might as well represent co-infections with B. burgdorferi s.l. We therefore investigated whether B. miyamotoi was present in LB-suspected skin lesions of patients referred to our tertiary Lyme disease clinic. 3360 questing Ixodes ricinus nymphs as well as spleen tissue of 74 rodents, 26 birds and 10 deer were tested by PCR for the presence of B. miyamotoi. Tick lysates were also tested for the presence of B. burgdorferi s.l. Next, we performed a PCR for B. miyamotoi in 31 biopsies from LB-suspected skin lesions in patients visiting our tertiary Lyme center. These biopsies had been initially tested for B. burgdorferi s.l. by PCR, and the skin lesions had been investigated by specialized dermatologists. Out of 3360 unfed (or questing) nymphs, 313 (9.3%) were infected with B. burgdorferi s.l., 70 (2.1%) were infected with B. miyamotoi, and 14 (0.4%) were co-infected with B. burgdorferi s.l. and B. miyamotoi. Co-infection of B. burgdorferi s.l. with B. miyamotoi occurred more often than expected from single infection prevalences (p=0.03). Both rodents (9%) and birds (8%) were found positive for B. miyamotoi by PCR, whereas the roe deer samples were negative. Out of 31 LB-suspected skin biopsies, 10 (32%) were positive for B. burgdorferi s.l. while none were positive for B. miyamotoi. The significant association of B. burgdorferi s.l. with B. miyamotoi in nymphs implies the existence of mutual reservoir hosts. Indeed, the presence of B. miyamotoi DNA indicates systemic infections in birds as well as rodents. However, their relative contributions to the enzootic cycle of B. miyamotoi requires further investigation. We could not retrospectively diagnose B. miyamotoi infection using biopsies of LB-suspected skin lesions, supporting the hypothesis that B. miyamotoi is not associated with LB-associated skin manifestations. However, this warrants further studies in larger sets of skin biopsies. A prospective study focused on acute febrile illness after a tick bite could provide insight into the incidence and clinical manifestations of B. miyamotoi infection in The Netherlands.

Borrelia miyamotoi: A human tick-borne relapsing fever spirochete in Europe and its potential impact on public health

Borrelia miyamotoi is a tick-borne bacterium which has only recently been identified in Europe as a human pathogen causing relapsing fever and little is known about its local impact on human health. There are three types of B. miyamotoi: Asian (Siberian), European, and American. B. miyamotoi is transmitted by the same Ixodes ricinus-persulcatus species complex, which also transmits B. burgdorferi s.l., the Lyme borreliosis group. Both Borrelia groups are mostly maintained in natural rodent populations. The aim of this review is to summarize the available literature on B. miyamotoi, with the focus of attention falling on Europe, as well as to describe its presence in ticks, reservoir hosts, and humans and discuss its potential impact on public health.

Occurrence of Borrelia burgdorferi Sensu Lato in Ixodes ricinus Ticks with First Identification of Borrelia miyamotoi in Vojvodina, Serbia

Lyme borreliosis is the most common tick-borne infectious disease in Eurasia. Borrelia miyamotoi is the only known relapsing fever Borrelia group spirochete transmitted by Ixodes species. The aim of this study was to investigate the presence of Lyme Borrelia spp. and relapsing fever Borrelia spp. in Ixodes ricinus ticks collected from dogs and the vegetation from different parts of Vojvodina, Serbia. A total of 71 Ixodes ricinus ticks were collected and screened for the presence of Lyme Borrelia spp. group and relapsing fever Borrelia spp. by real-time PCR for the Borrelia flagellin B (flaB) gene followed by DNA sequencing of PCR products. Species identification was verified by PCR of the outer surface protein A (ospA) gene for Lyme Disease Borrelia spp. and by PCR of the glycerophosphodiester phosphodiesterase (glpQ) gene for relapsing fever Borrelia spp. Lyme Borrelia spp. were found in 15/71 (21.13%) of the ticks evaluated and included B. luisitaniae (11.3%), B. afzelii (7%), B. valaisiana (1.4%), and B. garinii (1.4%). Borrelia miyamotoi, from the relapsing fever Borrelia complex, was found, for the first time in Serbia, in one (1.4%) nymph collected from the environment. Co-infections between Borrelia species in ticks were not detected. These results suggest that the dominance of species within B. burgdorferi s.l. complex in I. ricinus ticks may vary over time and in different geographic regions. Further systematic studies of Borrelia species in vectors and reservoir hosts are needed to understand eco-epidemiology of these zoonotic infections and how to prevent human infection in the best way.

Surveillance of ticks and associated pathogens in free-ranging Formosan pangolins (Manis pentadactyla pentadactyla)

Chinese pangolins are critically endangered insectivorous mammals distributed in several South and Southeast Asian countries. In recent years, there has been an increase in spread of tick-borne diseases in both humans and animals worldwide. Currently, limited information is available on ticks and associated pathogens infesting pangolins. The objective of the present study was to survey ticks and associated pathogens in the Formosan pangolin population in Southeastern Taiwan. Free-ranging Formosan pangolins captured during ecological survey were examined for the presence of ticks. DNA extracted from these ticks was used to identify the tick species and also to detect the tick-borne pathogens, by molecular methods. In the present study, we found 25% (13/52) of pangolins captured during 2012-2014 infested with ixodid ticks. A total of 21 ticks were collected and 3 species were identified: Haemaphysalis hystricis (14/21), Haemaphysalis formosensis (2/21) and Amblyomma testudinarium (5/21). We detected four different tick-borne pathogens, where one was identical to Anaplasma sp. strain An.H1446 while others showed close resemblance to Rickettsia conorii subsp. caspia A-167, Ehrlichia sp. TC251-2 and Cytauxzoon spp., respectively. The present study is the first survey of ticks infesting the free-ranging Chinese pangolins and pathogens harboured by these ticks. This information is important to know the diversity of ticks and tick-borne pathogens, and its conservation significance to pangolins and other sympatric wildlife. Important future step should be regular surveillance of ticks and tick-borne diseases at human-domestic animals-wildlife interface, which can provide a useful insight into the dynamics of these pathogens and can help control and prevent outbreak of zoonoses.

Dermacentor reticulatus: a vector on the rise

Dermacentor reticulatus is a hard tick species with extraordinary biological features. It has a high reproduction rate, a rapid developmental cycle, and is also able to overcome years of unfavourable conditions. Dermacentor reticulatus can survive under water for several months and is cold-hardy even compared to other tick species. It has a wide host range: over 60 different wild and domesticated hosts are known for the three active developmental stages. Its high adaptiveness gives an edge to this tick species as shown by new data on the emergence and establishment of D. reticulatus populations throughout Europe. The tick has been the research focus of a growing number of scientists, physicians and veterinarians. Within the Web of Science database, more than a fifth of the over 700 items published on this species between 1897 and 2015 appeared in the last three years (2013–2015). Here we attempt to synthesize current knowledge on the systematics, ecology, geographical distribution and recent spread of the species and to highlight the great spectrum of possible veterinary and public health threats it poses. Canine babesiosis caused by Babesia canis is a severe leading canine vector-borne disease in many endemic areas. Although less frequently than Ixodes ricinus, D. reticulatus adults bite humans and transmit several Rickettsia spp., Omsk haemorrhagic fever virus or Tick-borne encephalitis virus. We have not solely collected and reviewed the latest and fundamental scientific papers available in primary databases but also widened our scope to books, theses, conference papers and specialists colleagues’ experience where needed. Besides the dominant literature available in English, we also tried to access scientific literature in German, Russian and eastern European languages as well. We hope to inspire future research projects that are necessary to understand the basic life-cycle and ecology of this vector in order to understand and prevent disease threats. We conclude that although great strides have been made in our knowledge of the eco-epidemiology of this species, several gaps still need to be filled with basic research, targeting possible reservoir and vector roles and the key factors resulting in the observed geographical spread of D. reticulatus.

Identification of Hepatozoon erhardovae Krampitz, 1964 from bank voles (Myodes glareolus) and fleas in Southern Hungary

In order to investigate the prevalence and life cycle of apicomplexan parasites, small mammals were live-trapped with modified Sherman traps in Southern Hungary between 2010 and 2012. Altogether, 528 rodents (Apodemus flavicollis Melchior, 1834, Apodemus agrarius Pallas, 1771, Myodes glareolus Schreber, 1780, Microtus agrestis Linnaeus, 1761, Mus musculus Linnaeus, 1758 and Micromys minutus Pallas, 1771) were collected and four shrews (Sorex spp.) were by-catched. Captured animals belonging to non-protected species were euthanized, and spleen samples were preserved for histological and molecular analyses. During the examination of spleen smears, Hepatozoon parasites were observed in eight out of 48 bank voles (M. glareolus). DNA was isolated from altogether 221 spleen samples, and 18S rDNA was amplified using two different PCR protocols. The eight bank vole samples were positive with PCR, but none of the other M. glareolus spleen samples or any of the tissue samples from other species were found to be infected. Sequenced amplicons were very similar to Hepatozoon spp. detected in M. glareolus in Spain and Poland. Ectoparasites were collected from the small mammal carcasses and from the vegetation. Hepatozoon DNA was not found in the 181 ticks removed from the small mammals or in the 162 ticks collected with flagging, but was detected in all three flea species (4/43 Megabothris turbidus Rothschild, 1909, 3/10 Ctenophthalmus assimilis Taschenberg, 1880 and 7/78 Ctenophthalmus agyrtes Heller, 1896). Based on gamont morphology, vertebrate and arthropod host species and DNA sequences, the parasites in our study can be identified as Hepatozoon erhardovae.