Associations between coinfection prevalence of Borrelia lusitaniae, Anaplasma sp., and Rickettsia sp. in hard ticks feeding on reptile hosts

Bacterial pathogens in Ixodes ricinus collected from lizards Lacerta agilis and Zootoca vivipara in urban areas of Wrocław, SW Poland- preliminary study

The aim of this study was to determine the level of infection of Ixodes ricinus ticks with pathogens (Borrelia spp., Rickettsia spp., and Anaplasma spp.) collected from Lacerta agilis and Zootoca vivipara lizards in the urban areas of Wrocław (SW Poland). The study was carried out in July-August 2020. Lizards were caught by a noose attached to a pole or by bare hands, identified by species, and examined for the presence of ticks. Each lizard was then released at the site of capture. Ticks were removed with tweezers, identified by species using keys, and molecular tests were performed for the presence of pathogens. From 28 lizards (17 specimens of Z. vivipara and 11 specimens of L. agilis) a total of 445 ticks, including 321 larvae and 124 nymphs, identified as I. ricinus were collected. A larger number of ticks were obtained from L. agilis compared to Z. vivipara. Molecular tests for the presence of pathogens were performed on 445 specimens of I. ricinus. The nested PCR method for the fla gene allowed the detection of Borrelia spp. in 9.4% of ticks, and it was higher in ticks from L. agilis (12.0%) than from Z. vivipara (1.0%). The RFLP method showed the presence of three species, including two belonging to the B. burgdorferi s.l. complex (B. lusitaniae and B. afzelii), and B. miyamotoi. The overall level of infection of Rickettsia spp. was 19.3%, including 27.2% in ticks collected from Z. vivipara and 17.0% from L. agilis. Sequencing of randomly selected samples confirmed the presence of R. helvetica. DNA of Anaplasma spp. was detected only in one pool of larvae collected from L. agilis, and sample sequencing confirmed the presence of (A) phagocytophilum. The research results indicate the important role of lizards as hosts of ticks and their role in maintaining pathogens in the environment including urban agglomeration as evidenced by the first recorded presence of (B) miyamotoi and (A) phagocytophilum in I. ricinus ticks collected from L. agilis. However, confirmation of the role of sand lizards in maintaining (B) miyamotoi and A. phagocytophilum requires more studies and sampling of lizard tissue.

The role of wildlife in the epidemiology of tick-borne diseases in Slovakia

Tick-borne diseases (TBD) represent an important challenge for human and veterinary medicine. In Slovakia, studies on the epidemiology of tick-borne pathogens (TBP) regarding reservoir hosts have focused on small mammals and to a lesser extent on birds or lizards, while knowledge of the role of the remaining vertebrate groups is limited. Generally, wild ungulates, hedgehogs, small- and medium-sized carnivores, or squirrels are important feeding hosts for ticks and serve as reservoirs for TBP. Importantly, because they carry infected ticks and/or are serologically positive, they can be used as sentinels to monitor the presence of ticks and TBP in the environment. With their increasing occurrence in urban and suburban habitats, wild ungulates, hedgehogs or foxes are becoming an important component in the developmental cycle of Ixodes ricinus and of TBP such as Anaplasma phagocytophilum or Babesia spp. On the other hand, it has been postulated that cervids may act as dilution hosts for Borrelia burgdorferi (sensu lato) and tick-borne encephalitis virus. In southwestern Slovakia, a high prevalence of infection with Theileria spp. (100%) was observed in some cervid populations, while A. phagocytophilum (prevalence of c.50%) was detected in cervids and wild boars. The following pathogens were detected in ticks feeding on free-ranging ungulates, birds, and hedgehogs: A. phagocytophilum, Rickettsia spp., Coxiella burnetii, Neoehrlichia mikurensis, B. burgdorferi (s.l.), and Babesia spp. The growing understanding of the role of wildlife as pathogen reservoirs and carriers of pathogen-infected ticks offers valuable insights into the epidemiology of TBP, providing a foundation for reducing the risk of TBD.

Ticks and their epidemiological role in Slovakia: from the past till present

In Slovakia, 22 tick species have been found to occur to date. Among them, Ixodes ricinus, Dermacentor reticulatus, D. marginatus and marginally Haemaphysalis concinna, H. inermis and H. punctata have been identified as the species of public health relevance. Ticks in Slovakia were found to harbour and transmit zoonotic and/or potentially zoonotic agents such as tick-borne encephalitis virus (TBEV), spirochaetes of the Borrelia burgdorferi sensu lato (s.l.) complex, the relapsing fever sprirochaete Borrelia miyamotoi, bacteria belonging to the orders Rickettsiales (Rickettsia spp., Anaplasma phagocytophilum, Neoehrlichia mikurensis), Legionellales (Coxiella burnetii), and Thiotrichales (Francisella tularensis), and Babesia spp. parasites (order Piroplasmida). Ixodes ricinus is the principal vector of the largest variety of microorganisms including viruses, bacteria and piroplasms. TBEV, B. burgdorferi s.l., rickettsiae of the spotted fever group, C. burnetii and F. tularensis have been found to cause serious diseases in humans, whereas B. miyamotoi, A. phagocytophilum, N. mikurensis, Babesia microti, and B. venatorum pose lower or potential risk to humans. Distribution of TBEV has a focal character. During the last few decades, new tick-borne encephalitis (TBE) foci and their spread to new areas have been registered and TBE incidence rates have increased. Moreover, Slovakia reports the highest rates of alimentary TBE infections among the European countries. Lyme borreliosis (LB) spirochaetes are spread throughout the distribution range of I. ricinus. Incidence rates of LB have shown a slightly increasing trend since 2010. Only a few sporadic cases of human rickettsiosis, anaplasmosis and babesiosis have been confirmed thus far in Slovakia. The latest large outbreaks of Q fever and tularaemia were recorded in 1993 and 1967, respectively. Since then, a few human cases of Q fever have been reported almost each year. Changes in the epidemiological characteristics and clinical forms of tularaemia have been observed during the last few decades. Global changes and development of modern molecular tools led to the discovery and identification of emerging or new tick-borne microorganisms and symbionts with unknown zoonotic potential. In this review, we provide a historical overview of research on ticks and tick-borne pathogens in Slovakia with the most important milestones and recent findings, and outline future directions in the investigation of ticks as ectoparasites and vectors of zoonotic agents and in the study of tick-borne diseases.

Reptile vector-borne diseases of zoonotic concern

Reptile vector-borne diseases (RVBDs) of zoonotic concern are caused by bacteria, protozoa and viruses transmitted by arthropod vectors, which belong to the subclass Acarina (mites and ticks) and the order Diptera (mosquitoes, sand flies and tsetse flies). The phyletic age of reptiles since their origin in the late Carboniferous, has favored vectors and pathogens to co-evolve through millions of years, bridging to the present host-vector-pathogen interactions. The origin of vector-borne diseases is dated to the early cretaceous with Trypanosomatidae species in extinct sand flies, ancestral of modern protozoan hemoparasites of zoonotic concern (e.g., Leishmania and Trypanosoma) associated to reptiles. Bacterial RVBDs are represented by microorganisms also affecting mammals of the genera Aeromonas, Anaplasma, Borrelia, Coxiella, Ehrlichia and Rickettsia, most of them having reptilian clades. Finally, reptiles may play an important role as reservoirs of arborivuses, given the low host specificity of anthropophilic mosquitoes and sand flies. In this review, vector-borne pathogens of zoonotic concern from reptiles are discussed, as well as the interactions between reptiles, arthropod vectors and the zoonotic pathogens they may transmit.

Investigation of Tick-Borne Pathogens in Ixodes ricinus in a Peri-Urban Park in Lombardy (Italy) Reveals the Presence of Emerging Pathogens

Ticks are important vectors of a great range of pathogens of medical and veterinary importance. Lately, the spread of known tick-borne pathogens has been expanding, and novel ones have been identified as (re)emerging health threats. Updating the current knowledge on tick-borne pathogens in areas where humans and animals can be easily exposed to ticks represents a starting point for epidemiological studies and public awareness. A PCR screening for tick-borne pathogens was carried out in Ixodes ricinus ticks collected in a peri-urban recreational park in Ticino Valley, Italy. The presence of Rickettsia spp., Borrelia burgdorferi senso latu complex, Anaplasma spp. and Babesia spp. was evaluated in a total of 415 I. ricinus specimens. Rickettsia spp. (R monacensis and R. helvetica) were detected in 22.96% of the samples, while B. burgdorferi s.l. complex (B. afzelii and B. lusitaniae) were present in 10.94%. Neoehrlichia mikurensis (1.99%) and Babesia venatorum (0.73%) were reported in the area of study for the first time. This study confirmed the presence of endemic tick-borne pathogens and highlighted the presence of emerging pathogens that should be monitored especially in relation to fragile patients, the difficult diagnosis of tick-borne associated diseases and possible interactions with other tick-borne pathogens.

Virus Prevalence and Genetic Diversity Across a Wild Bumblebee Community

Viruses are key population regulators, but we have limited knowledge of the diversity and ecology of viruses. This is even the case in wild host populations that provide ecosystem services, where small fitness effects may have major ecological impacts in aggregate. One such group of hosts are the bumblebees, which have a major role in the pollination of food crops and have suffered population declines and range contractions in recent decades. In this study, we investigate the diversity of four recently discovered bumblebee viruses (Mayfield virus 1, Mayfield virus 2, River Liunaeg virus, and Loch Morlich virus), and two previously known viruses that infect both wild bumblebees and managed honeybees (Acute bee paralysis virus and Slow bee paralysis virus) from isolates in Scotland. We investigate the ecological and environmental factors that determine viral presence and absence. We show that the recently discovered bumblebee viruses were more genetically diverse than the viruses shared with honeybees. Coinfection is potentially important in shaping prevalence: we found a strong positive association between River Liunaeg virus and Loch Morlich virus presence after controlling for host species, location and other relevant ecological variables. We tested for a relationship between environmental variables (temperature, UV radiation, wind speed, and prevalence), but as we had few sampling sites, and thus low power for site-level analyses, we could not conclude anything regarding these variables. We also describe the relationship between the bumblebee communities at our sampling sites. This study represents a first step in the description of predictors of bumblebee infection in the wild.

Role of reptiles and associated arthropods in the epidemiology of rickettsioses: A one health paradigm

We assessed the presence of Rickettsia spp., Coxiella burnetii and Anaplasma phagocytophilum in reptiles, their ectoparasites and in questing ticks collected in a nature preserve park in southern Italy, as well as in a peri-urban area in another region. We also investigated the exposure to these pathogens in forestry workers, farmers and livestock breeders living or working in the nature preserve park given the report of anecdotal cases of spotted fever rickettsioses. Rickettsia spp. were molecularly detected in Podarcis muralis and Podarcis siculus lizards (i.e., 3.1%), in Ixodes ricinus (up to 87.5%) and in Neotrombicula autumnalis (up to 8.3%) collected from them as well as in I. ricinus collected from the environment (up to 28.4%). Rickettsia monacensis was the most prevalent species followed by Rickettsia helvetica. An undescribed member of the family Anaplasmataceae was detected in 2.4% and 0.8% of the reptiles and ectoparasites, respectively. Sera from human subjects (n = 50) were serologically screened and antibodies to Rickettsia spp. (n = 4; 8%), C. burnetti (n = 8; 16%) and A. phagocytophilum (n = 11; 22%) were detected. Two ticks collected from two forestry workers were positive for spotted fever group (SFG) rickettsiae. Ixodes ricinus is involved in the transmission of SFG rickettsiae (R. monacensis and R. helvetica) in southern Europe and lizards could play a role in the sylvatic cycle of R. monacensis, as amplifying hosts. Meanwhile, N. autumnalis could be involved in the enzootic cycle of some SFG rickettsiae among these animals. People living or working in the southern Italian nature preserve park investigated are exposed to SFG rickettsiae, C. burnetii and A. phagocytophilum.

Zoonotic pathogens such as Rickettsia spp., Coxiella burnetii and Anaplasma phagocytophilum are associated with ticks, lice, fleas and mites and may infect a wide range of vertebrate species. There are still many knowledge gaps concerning the arthropod vectors and amplifying hosts of these pathogens. Reptiles are known to host infected ticks with these zoonotic pathogens and eventually become infected themselves by these bacteria. Hence to address this question from a broad One-Health perspective, we assessed the molecular prevalence of Rickettsia spp., C. burnetii and A. phagocytophilum in reptiles, ticks and mites from both hosts and environment and seroprevalence in humans living or working near the same area. Rickettsia DNA was detected in lizards’ tails, Ixodes ricinus ticks and in Neotrombicula autumnalis mites collected from them and in questing ticks. Although DNA of C. burnetii and A. phagocytophilum was not detected in lizards and their ectoparasites, sera samples of human subjects tested positive for the antibodies against these zoonotic pathogens. These findings indicate the epidemiological role of lizards in spreading SFG rickettsiae as well as I. ricinus, and hence representing a potential public health concern in geographical areas where lizards, ticks and humans share the same environment.

Molecular detection of vector-borne agents in ectoparasites and reptiles from Brazil

Trombidiformes and Mesostigmata mites, as well as Ixodida ticks, infest ectothermic tetrapods worldwide, potentially acting as vectors of bacteria, viruses and protozoa. The relationship among ectoparasites, transmitted pathogenic agents (e.g., Borrelia spp., Coxiella spp., Hepatozoon spp., and Rickettsia spp.) and ectothermic hosts has been scarcely investigated. This research focuses on a large collection of Brazilian herpetofauna screened for the presence of arthropod ectoparasites and vector-borne microbial agents. Reptiles (n = 121) and amphibians (n = 49) from various locations were infested by ectoparasites. Following genomic extraction, microbial agents were detected in 81 % of the Acari (i.e. n = 113 mites and n = 26 ticks). None of the mites, ticks and tissues from amphibians yielded positive results for any of the screened agents. Blood was collected from reptiles and processed through blood cytology and molecular analyses (n = 48). Of those, six snakes (12.5 %) showed intraerythrocytic alterations compatible with Hepatozoon spp. gamonts and Iridovirus inclusions. Hepatozoon spp. similar to Hepatozoon ayorgbor and Hepatozoon musa were molecularly identified from seven hosts, two mite and two tick species. Rickettsia spp. (e.g., Rickettsia amblyommatis, Rickettsia bellii-like, Rickettsia sp.) were detected molecularly from four mite species and Amblyomma rotundatum ticks. Phylogenetic analyses confirmed the molecular identification of the above-mentioned microbial agents of mites and ticks related to snakes and lizards. Overall, our findings highlighted that the Brazilian herpetofauna and its ectoparasites harbour potentially pathogenic agents, particularly from the northern and south-eastern regions. The detection of several species of spotted fever group Rickettsia pointed out the potential role of ectothermic hosts and related arthropod ectoparasites in the epidemiological cycle of these bacteria in Brazil.

Molecular detection of pathogens in ticks associated with domestic animals from the Colombian Caribbean region

Tick-borne diseases constitute a problem for livestock and public health. Given the socio-economic and environmental conditions of the Colombian Caribbean, ticks are particularly abundant, in turn exposing domestic animals and people in contact with them to such diseases. This study evaluates the presence of Babesia spp., Anaplasma spp., Coxiella spp. and Borrelia spp. in domestic animal ticks (Amblyomma mixtum, A. dissimile, Dermacentor nitens, Rhipicephalus sanguineus and R. microplus) by conventional PCR. Findings show a prevalence of 12.5% of Babesia, 0% of Borrelia, 39.4% of Anaplasma and 52.9% of Coxiella, whereas 6.2% of a total sample of 104 tick pools presented coinfections between Babesia and Anaplasma. Among the molecularly identified species are Ba. vogeli, Ba. bigemina and A. marginale, in addition to two Coxiella species-one being C. mudrowiae and the other similar to an undescribed endosymbiont of Rhipicephalus sp. It is necessary to evaluate the vector capacity of ticks such as A. mixtum, D. nitens and R. sanguineus in the transmission of A. marginale. Moreover, it is necessary to explore the role that bacteria of the genus Coxiella might have both in the health of humans and animals, and in the metabolism and reproduction of ticks. This is the first report on Babesia vogeli and B. bigemina in ticks from the Colombian Caribbean, representing a risk to animal and human health.

Detection and isolation of tick-borne bacteria (Anaplasma spp., Rickettsia spp., and Borrelia spp.) in Amblyomma varanense ticks on lizard (Varanus salvator)

Ticks are one of the arthropods that play an important role in the transmission of numerous pathogens to livestock and humans. We investigated the presence of tick-borne bacteria in 23 Amblyomma varanense that fed on a water monitor (Varanus salvator) in Indonesia. Anaplasmataceae and borreliae were detected by PCR in 17.4% and 95.7% of ticks, respectively. "Candidatus Rickettsia sepangensis", spotted fever group of Rickettsia, was detected in 21.7% of ticks. The water monitor is a common reptile that is widely encountered in city areas in Asian countries. Our results suggested that Am. varanense on water monitor in Indonesia harbored several kinds of bacteria.

Rickettsia species in ticks that parasitize amphibians and reptiles: Novel report from Mexico and review of the worldwide record

Ticks are obligate haematophagous ectoparasites that are associated with a wide range of vertebrate hosts, among them also reptiles and amphibians. They have dynamic ecological interactions with multiple microorganisms, ranging from endosymbionts to pathogens, such as the members of the genus Rickettsia. The aim of this work was to detect Rickettsia in ticks from amphibians and reptiles from southern Mexico by the amplification, sequencing and phylogenetic reconstruction of the gltA and ompA genes, and also to compile all the published records worldwide of Rickettsia associated with ticks attached to reptiles and amphibians, in order to elucidate the host-parasite relationships, and to identify the geographical distribution of each bacterial species. We record for the first time the presence of Rickettsia sp. strain Colombianensi and Rickettsia amblyommatis in ticks from several reptiles and amphibians collected in three new localities from the states of Guerrero and Veracruz, Mexico. Additionally, we here report 23 Rickettsia taxa associated with 18 tick species attached to 42 host taxa of amphibians and reptiles in 36 countries. Our findings increase the inventory of rickettsia reported in Mexico and summarizes the knowledge of these bacteria associated with ticks of this particular group of vertebrate host worldwide.

Seasonal Patterns in the Prevalence and Diversity of Tick-Borne Borrelia burgdorferi Sensu Lato, Anaplasma phagocytophilum and Rickettsia spp. in an Urban Temperate Forest in South Western Slovakia

In Europe, Ixodes ricinus is the most important vector of tick-borne zoonotic bacteria. It transmits spirochaetes from the Borrelia burgdorferi sensu lato complex, Anaplasma phagocytophilum and Rickettsia spp. Although spatial differences in the prevalence of tick-borne pathogens have been intensively studied, seasonal (within-year) fluctuations in the prevalence of these pathogens within sites are often overlooked. We analyzed the occurrence and seasonal dynamics of Ixodes ricinus in an urban forest in Bratislava, Slovakia. Furthemore, we examined temporal trends in the community structure of B. burgdorferi s.l., A. phagocytophilum and Rickettsia spp. in questing and bird-feeding ticks. The total prevalence for B. burgdorferi s.l. in questing I. ricinus was 6.8%, involving six genospecies with the dominance of bird-associated B. garinii and B. valaisiana.A. phagocytophilum, R. helvetica and R. monacensis occurred in 5.9%, 5.0% and 0.2% of questing ticks, respectively. In total, 12.5% and 4.4% of bird-feeding I. ricinus ticks carried B. burgdorferi s.l. and R. helvetica. The total prevalence of B. burgdorferi s.l. in our study site was two times lower than the mean prevalence for Europe. In contrast, A. phagocytophilum prevalence was significantly higher compared to those in other habitats of Slovakia. Our results imply that tick propagation and the transmission, suppression and seasonal dynamics of tick-borne pathogens at the study site were primarily shaped by abundance and temporal population fluctuations in ruminant and bird hosts.

Neglected aspects of tick-borne rickettsioses

Rickettsioses are among the oldest known infectious diseases. In spite of this, and of the extensive research carried out, many aspects of the biology and epidemiology of tick-borne rickettsiae are far from being completely understood. Their association with arthropod vectors, the importance of vertebrates as reservoirs, the rarity of clinical signs in animals, or the interactions of pathogenic species with rickettsial endosymbionts and with the host intracellular environment, are only some examples. Moreover, new rickettsiae are continuously being discovered. In this review, we focus on the ‘neglected’ aspects of tick-borne rickettsioses and on the gaps in knowledge, which could help to explain why these infections are still emerging and re-emerging threats worldwide.

Importance of Common Wall Lizards in the Transmission Dynamics of Tick-Borne Pathogens in the Northern Apennine Mountains, Italy

During the investigations on ticks and tick-borne pathogens (TBP) range expansion in the Northern Apennines, we captured 107 Podarcis muralis lizards. Sixty-eight animals were infested by immature Ixodes ricinus, Haemaphysalis sulcata and H. punctata. Borrelia burgdorferi s.l. was detected in 3.7% of I. ricinus larvae and 8.0% of nymphs. Together with the species-specific B. lusitaniae, we identified B. garinii, B. afzelii and B. valaisiana. Rickettsia spp. (18.1% larvae, 12.0% nymphs), namely R. monacensis, R. helvetica and R. hoogstraalii, were also found in I. ricinus. R. hoogstraalii was detected in H. sulcata nymphs as well, while the two H. punctata did not harbour any bacteria. One out of 16 lizard tail tissues was positive to R. helvetica. Our results support the hypothesis that lizards are involved in the epidemiological cycles of TBP. The heterogeneity of B. burgdorferi genospecies mirrors previous findings in questing ticks in the area, and their finding in attached I. ricinus larvae suggests that lizards may contribute to the maintenance of different genospecies. The rickettsiae are new findings in the study area, and R. helvetica infection in a tail tissue indicates a systemic infection. R. hoogstraalii is reported for the first time in I. ricinus ticks. Lizards seem to favour the bacterial exchange among different tick species, with possible public health consequences.

Tick-Borne Transmission of Murine Gammaherpesvirus 68

Herpesviruses are a large group of DNA viruses infecting mainly vertebrates. Murine gammaherpesvirus 68 (MHV68) is often used as a model in studies of the pathogenesis of clinically important human gammaherpesviruses such as Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus. This rodent virus appears to be geographically widespread; however, its natural transmission cycle is unknown. Following detection of MHV68 in field-collected ticks, including isolation of the virus from tick salivary glands and ovaries, we investigated whether MHV68 is a tick-borne virus. Uninfected Ixodes ricinus ticks were shown to acquire the virus by feeding on experimentally infected laboratory mice. The virus survived tick molting, and the molted ticks transmitted the virus to uninfected laboratory mice on which they subsequently fed. MHV68 was isolated from the tick salivary glands, consistent with transmission via tick saliva. The virus survived in ticks without loss of infectivity for at least 120 days, and subsequently was transmitted vertically from one tick generation to the next, surviving more than 500 days. Furthermore, the F1 generation (derived from F0 infected females) transmitted MHV68 to uninfected mice on which they fed, with MHV68 M3 gene transcripts detected in blood, lung, and spleen tissue of mice on which F1 nymphs and F1 adults engorged. These experimental data fulfill the transmission criteria that define an arthropod-borne virus (arbovirus), the largest biological group of viruses. Currently, African swine fever virus (ASFV) is the only DNA virus recognized as an arbovirus. Like ASFV, MHV68 showed evidence of pathogenesis in ticks. Previous studies have reported MHV68 in free-living ticks and in mammals commonly infested with I. ricinus, and neutralizing antibodies to MHV68 have been detected in large mammals (e.g., deer) including humans. Further studies are needed to determine if these reports are the result of tick-borne transmission of MHV68 in nature, and whether humans are at risk of infection.

Association of Borrelia and Rickettsia spp. and bacterial loads in Ixodes ricinus ticks

In recent years, awareness of coinfections has increased as synergistic or antagonistic effects on interacting bacteria have been observed. To date, several reports on coinfections of ticks with Rickettsia and Borrelia spp. are available. However, associations are rarely described and studies are based on rather low sample sizes. In the present study, coinfections of Ixodes ricinus with these pathogens were investigated by determining their association in a meta-analysis. A total of 5079 tick samples examined for Rickettsia and Borrelia spp. via probe-based quantitative real-time PCR in previous prevalence studies or as submitted diagnostic material were included. In Borrelia-positive ticks, genospecies were determined by Reverse Line Blot. Determination of bacterial loads resulted in an increase between developmental tick stages with highest mean bacterial loads in female ticks (7.96×10⁴ in Borrelia single-infected, 4.87×10⁵ in Rickettsia single-infected and 3.22×10⁵ in Borrelia-Rickettsia coinfected females). The determined Borrelia-Rickettsia tick coinfection rate was 12.3% (626/5079) with a significant difference to the expected coinfection rate of 9.0% (457/5079). A significant slight association as well as correlation between Borrelia and Rickettsia were determined. In addition, a significant interrelation of the bacterial load in coinfected ticks was shown. At the level of Borrelia genospecies, significant weak associations with Rickettsia spp. were detected for B. afzelii, B. garinii/bavariensis, B. valaisiana and B. lusitaniae. The positive association provides evidence for interactions between Borrelia and Rickettsia spp. in the tick vector, presumably resulting in higher bacterial replication rates in the tick vector and possibly the reservoir host. However, coinfection may impact the vector negatively as indicated by an absent increase in coinfection rates from nymphs to adults. Future studies are needed to investigate the underlying mechanisms of the positive association in ticks and possible associations in the vertebrate host as well as the potential influence of environmental factors.

Haemosporidian infections affect antioxidant defences in great tits Parus major but are not related to exposure to aerial pollutants

Haemosporidian parasites are widespread in avian species and modulate their ecology, behaviour, life-history and fitness. The prevalence of these vector-transmitted parasites varies with host intrinsic and extrinsic factors, such as host resistance and behaviour, and habitat-related characteristics. In this study, we evaluated the prevalence of avian haemosporidians in great tit Parus major populations inhabiting two areas with different degrees of exposure to aerial emissions from pulp mills, to assess if this type of pollution impacted parasite prevalence. We also compared the physiological condition of infected and uninfected individuals. Haemosporidian infection prevalence was high (58%), varied seasonally, but was not associated with air pollution exposure. Fledged birds presented higher infection rates than nestlings and infected fledged birds had higher levels of blood glutathione peroxidase activity. These results allow us to infer that infection by blood parasites may activate antioxidant defences, possibly to protect the organism from the negative oxidative stress side-effects of immune activation against parasites. Because oxidative stress is one of the mechanisms responsible for ageing and senescence and may affect fitness, the relationship between parasitism and oxidative stress markers should be further investigated through studies that include experimental manipulation of infection in model organisms.

The risk of exposure to rickettsial infections and human granulocytic anaplasmosis associated with Ixodes ricinus tick bites in humans in Romania: A multiannual study

Anaplasma phagocytophilum and spotted fever group Rickettsia are obligate intracellular Gram-negative tick-borne bacteria, among which several may cause clinical infections in humans. Several Rickettsia spp. and A. phagocytophilum are transmitted in Europe by Ixodes ricinus, the most common tick species feeding on humans in this area. The aim of this study was to evaluate the annual prevalence of Rickettsia spp. and A. phagocytophilum in I. ricinus collected from humans during three consecutive years. The mean prevalences of the infection with the investigated pathogens in I. ricinus ticks collected from human patients were as follows: A. phagocytophilum (5.56%), R. helvetica (4.79%) and R. monacensis (1.53%). In the present study, no significant differences of pathogens prevalence between the three years study period were observed, except the prevalence of R. helvetica, which had a significant increase in 2015, suggesting an increasing risk for humans to be exposed to this zoonotic pathogen.

Rickettsia species in fleas collected from small mammals in Slovakia

Epidemiological and epizootiological studies of Rickettsia felis and other Rickettsia spp. are very important, because their natural cycle has not yet been established completely. In total, 315 fleas (Siphonaptera) of 11 species of Ceratophyllidae, Hystrichopsyllidae and Leptopsyllidae families were tested for the presence of Rickettsia species and Coxiella burnetii with conventional and specific quantitative real-time PCR assays. Fleas were collected from five rodent hosts (Myodes glareolus, Apodemus flavicollis, Apodemus agrarius, Microtus subterraneus, Microtus arvalis) and three shrew species (Sorex araneus, Neomys fodiens, Crocidura suaveolens) captured in Eastern and Southern Slovakia. Overall, Rickettsia spp. was found in 10.8% (34/315) of the tested fleas of Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus uncinatus and Nosopsyllus fasciatus species. Infected fleas were coming from A. flavicollis, A. agrarius, and M. glareolus captured in Eastern Slovakia. C. burnetii was not found in any fleas. R. felis, Rickettsia helvetica, unidentified Rickettsia, and rickettsial endosymbionts were identified in fleas infesting small mammals in the Košice region, Eastern Slovakia. This study is the first report of R. felis infection in C. solutus male flea collected from A. agrarius in Slovakia.

Detection of Rickettsia and Ehrlichia spp. in Ticks Associated with Exotic Reptiles and Amphibians Imported into Japan

One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma) were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia). None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA), and outer membrane protein A (ompA) were positively detected in 45.2% (42/93), 40.9% (38/93), and 23.7% (22/93) of the ticks, respectively, by polymerase chain reaction (PCR). The genes encoding ehrlichial heat shock protein (groEL) and major outer membrane protein (omp-1) were PCR-positive in 7.5% (7/93) and 2.2% (2/93) of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known and potential pathogens carried by ticks in reptiles, amphibians, and other animals, in order to improve national and international public health.

Spotted fever group rickettsiae detected in immature stages of ticks parasitizing on Iberian endemic lizard Lacerta schreiberi Bedriaga, 1878

Spotted fever rickettsioses are tick-borne diseases of growing public health concern. The prevalence of rickettsia-infected ticks and their ability to parasitize humans significantly influence the risk of human infection. Altogether 466 Ixodes ricinus ticks (428 nymphs and 38 larvae) collected from 73 Lacerta schreiberi lizards were examined by PCR targeting the citrate synthetase gene gltA for the presence of Rickettsia spp. Rickettsial DNA was detected in 47% of nymphs and 31.6% of larvae. They were subsequently subjected to a second PCR reaction using primers derived from the outer membrane protein rOmpA encoding gene (ompA) to detect spotted fever group rickettsiae (SFG). This analysis shows that 41.4% of nymphs and 7.9% of larvae collected from the lizards contain DNA of SFG rickettsiae. Sequencing of 43 randomly selected samples revealed two different haplotypes, both closely related to R. monacensis (39 and 4 samples, respectively). The remaining ompA negative Rickettsia spp. samples were determined to be R. helvetica based on sequencing of ompB and gltA fragments. Our results indicate that the role of Iberian endemic lizard L. schreiberi and its ectoparasites in the ecology and epidemiology of zoonotic SFG rickettsioses may be appreciable.

Cercopithifilaria rugosicauda (Spirurida, Onchocercidae) in a roe deer and ticks from southern Italy

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First report of Cercopithifilaria rugosicauda in a roe deer and ticks from Italy.

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This study provides new morphological data on this little known nematode.

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The genetic data provide for the first time information on mitochondrial genes of C. rugosicauda.

Cercopithifilaria rugosicauda (Spirurida, Onchocercidae) is a subcutaneous filarial nematode of the European roe deer (Capreolus capreolus) transmitted by Ixodes ricinus (Acari, Ixodidae). At the necropsy of a roe deer from the Parco Regionale di Gallipoli Cognato (Basilicata region, southern Italy), two female nematodes of C. rugosicauda were found. Following the necropsy, seven skin snips were sampled from different body regions and 96 I. ricinus ticks were collected. In addition, 240 ticks were collected by dragging in the enclosure where the roe deer lived. Samples were examined for the presence of C. rugosicauda larvae and assayed by PCR targeting cytochrome c oxidase subunit 1 (cox1, ∼300 bp) and 12S rDNA (∼330 bp) gene fragments. Female nematodes, microfilariae from skin samples and eight third stage larvae (L3) from ticks were morphologically and molecularly identified as C. rugosicauda. Phylogenetic analyses clustered this species with other sequences of Cercopithifilaria spp. This study represents the first report of C. rugosicauda in a roe deer and ticks from Italy and provides new morphological and molecular data on this little known nematode.

Rickettsial infection in Ixodes ricinus ticks in urban and natural habitats of Slovakia

A total of 1810 Ixodes ricinus ticks was collected from the vegetation from 2 different habitat types: urban and natural. Urban habitats were represented by cemeteries and public parks in the following towns: Bratislava, Malacky, and Martin at 150 m and 400 m above sea level. Natural habitats were selected in the mountain forest of the Martinské hole Mts. in Central Slovakia at 3 different altitudinal levels, i.e. 600 m, 800 m and 1000 ma.s.l. All ticks were tested for the presence of spotted fever group rickettsiae. The DNA of Rickettsia spp. was identified in 9% of all tested ticks. Rickettsia-infected ticks were present in both, urban and sylvatic sites at all studied altitudes. Four different species of Rickettsia were present in positive I. ricinus ticks. Rickettsia helvetica was identified in 77 out of 87 Rickettsia-positive I. ricinus ticks, followed by 8 samples that belonged to Rickettsia monacensis and 2 of the positive ticks were infected with different unidentified Rickettsia spp. Due to the association of R. helvetica and R. monacensis with human infections, it is essential to understand which species of Rickettsia circulate in the natural foci of Slovakia. Circulation of pathogenic rickettsiae in urban as well as natural habitats at different altitudinal levels in Slovakia emphasizes that infection risk is very common throughout this Central European country.

Molecular detection of murine herpesvirus 68 in ticks feeding on free-living reptiles

The MHV-68 (designed as Murid herpesvirus 4 (MuHV 4) strain 68) isolated from two rodents, Myodes glareolus and Apodemus flavicollis, is considered as a natural pathogen of free-living murid rodents. Recently, the detection of MHV antibodies in the blood of animals living in the same biotope as MHV-infected mice has suggested that ticks may have a role in the transmission of this pathogen. Ixodes ricinus is one the most abundant tick species in Europe known to transmit multiple pathogens causing human and animal diseases. In this study, nymphs and larvae feeding on 116 individuals of a temperate lizard species-the green lizard Lacerta viridis captured in the Slovak Karst National Park, were examined for MHV-68. The specific sequence of virion glycoprotein 150 was amplified in DNA individually isolated from I. ricinus ticks using single-copy sensitive nested polymerase chain reaction. MHV-68 was detected in ten of 649 nymphs and in five of 150 larvae, respectively. We found that 9.6% of green lizards fed at least one MHV-68-infected immature tick. Occurrence of MHV-68 within all ticks tested was 1.8%. This study is first to show that immature I. ricinus ticks feeding on free-living lizards in a Central European region could be infected with gammaherpesvirus (MHV-68), naturally infecting free-living murid rodents. Our results provide evidence supporting the hypothesis that ticks may play a mediating role in circulation of MHV-68 in nature.

Anaplasmataceae and Borrelia burgdorferi sensu lato in the sand lizard Lacerta agilis and co-infection of these bacteria in hosted Ixodes ricinus ticks

BACKGROUND

Anaplasmataceae and Borrelia burgdorferi s.l. are important tick-borne bacteria maintained in nature by transmission between ticks and vertebrate hosts. However, the potential role of lizards as hosts has not been sufficiently studied.

RESULTS

The current study showed that 23 of 171 examined sand lizards Lacerta agilis were PCR positive for Anaplasmataceae. The nucleotide sequences of the several selected PCR products showed 100% homology with Anaplasma spp. found in Ixodes ricinus collected in Tunisia and Morocco (AY672415 - AY672420). 1.2% of lizard collar scale samples were PCR positive for B. lusitaniae. In addition, 12 of 290 examined I. ricinus were PCR positive for B. burgdorferi s.l. and 82 were PCR positive for Anaplasmatacea. The number of ticks per lizard and the number of ticks PCR positive for both microorganisms per lizard were strongly correlated. Moreover, we found a significant correlation between numbers of ticks infected with Anaplasmataceae and with B. burgdorferi s.l. living on the same lizard. However, there was no significant correlation between detection of both bacteria in the same tick.

CONCLUSIONS

To the best of our knowledge, this is the first report of Anaplasmataceae DNA and additionally the second report of B. burgdorferi s.l DNA detection in the sand lizard.