• Cascading effects of predator activity on tick-borne disease risk.

      Hofmeester, Tim R; Jansen, Patrick A; Wijnen, Hendrikus J; Coipan, Elena C; Fonville, Manoj; Prins, Herbert H T; Sprong, Hein; van Wieren, Sipke E (2017-07-26)
      Predators and competitors of vertebrates can in theory reduce the density of infected nymphs (DIN)-an often-used measure of tick-borne disease risk-by lowering the density of reservoir-competent hosts and/or the tick burden on reservoir-competent hosts. We investigated this possible indirect effect of predators by comparing data from 20 forest plots across the Netherlands that varied in predator abundance. In each plot, we measured the density of questing Ixodes ricinus nymphs (DON), DIN for three pathogens, rodent density, the tick burden on rodents and the activity of mammalian predators. We analysed whether rodent density and tick burden on rodents were correlated with predator activity, and how rodent density and tick burden predicted DON and DIN for the three pathogens. We found that larval burden on two rodent species decreased with activity of two predator species, while DON and DIN for all three pathogens increased with larval burden on rodents, as predicted. Path analyses supported an indirect negative correlation of activity of both predator species with DON and DIN. Our results suggest that predators can indeed lower the number of ticks feeding on reservoir-competent hosts, which implies that changes in predator abundance may have cascading effects on tick-borne disease risk.
    • Circulation of Species and Their Exposure to Humans through .

      Azagi, Tal; Jaarsma, Ryanne I; Docters van Leeuwen, Arieke; Fonville, Manoj; Maas, Miriam; Franssen, Frits F J; Kik, Marja; Rijks, Jolianne M; Montizaan, Margriet G; Groenevelt, Margit; et al. (2021-03-24)
      Human babesiosis in Europe has been attributed to infection with Babesia divergens and, to a lesser extent, with Babesia venatorum and Babesia microti, which are all transmitted to humans through a bite of Ixodes ricinus. These Babesia species circulate in the Netherlands, but autochthonous human babesiosis cases have not been reported so far. To gain more insight into the natural sources of these Babesia species, their presence in reservoir hosts and in I. ricinus was examined. Moreover, part of the ticks were tested for co-infections with other tick borne pathogens. In a cross-sectional study, qPCR-detection was used to determine the presence of Babesia species in 4611 tissue samples from 27 mammalian species and 13 bird species. Reverse line blotting (RLB) and qPCR detection of Babesia species were used to test 25,849 questing I. ricinus. Fragments of the 18S rDNA and cytochrome c oxidase subunit I (COI) gene from PCR-positive isolates were sequenced for confirmation and species identification and species-specific PCR reactions were performed on samples with suspected mixed infections. Babesia microti was found in two widespread rodent species: Myodes glareolus and Apodemus sylvaticus, whereas B. divergens was detected in the geographically restricted Cervus elaphus and Bison bonasus, and occasionally in free-ranging Ovis aries. B. venatorum was detected in the ubiquitous Capreolus capreolus, and occasionally in free-ranging O. aries. Species-specific PCR revealed co-infections in C. capreolus and C. elaphus, resulting in higher prevalence of B. venatorum and B. divergens than disclosed by qPCR detection, followed by 18S rDNA and COI sequencing. The non-zoonotic Babesia species found were Babesia capreoli, Babesia vulpes, Babesia sp. deer clade, and badger-associated Babesia species. The infection rate of zoonotic Babesia species in questing I. ricinus ticks was higher for Babesia clade I (2.6%) than Babesia clade X (1.9%). Co-infection of B. microti with Borrelia burgdorferi sensu lato and Neoehrlichia mikurensis in questing nymphs occurred more than expected, which reflects their mutual reservoir hosts, and suggests the possibility of co-transmission of these three pathogens to humans during a tick bite. The ubiquitous spread and abundance of B. microti and B. venatorum in their reservoir hosts and questing ticks imply some level of human exposure through tick bites. The restricted distribution of the wild reservoir hosts for B. divergens and its low infection rate in ticks might contribute to the absence of reported autochthonous cases of human babesiosis in the Netherlands.
    • Detection of Anaplasma phagocytophilum in European brown hares (Lepus europaeus) using three different methods.

      Lesiczka, Paulina Maria; Modry, David; Sprong, Hein; Fonville, Manoj; Pikula, Jiri; Piacek, Vladimir; Heger, Tomas; Hrazdilova, Kristyna (2021-08-11)
    • Diverse tick-borne microorganisms identified in free-living ungulates in Slovakia.

      Kazimírová, Mária; Hamšíková, Zuzana; Špitalská, Eva; Minichová, Lenka; Mahríková, Lenka; Caban, Radoslav; Sprong, Hein; Fonville, Manoj; Schnittger, Leonhard; Kocianová, Elena (2018-09-03)
      Free-living ungulates are hosts of ixodid ticks and reservoirs of tick-borne microorganisms in central Europe and many regions around the world. Tissue samples and engorged ticks were obtained from roe deer, red deer, fallow deer, mouflon, and wild boar hunted in deciduous forests of south-western Slovakia. DNA isolated from these samples was screened for the presence of tick-borne microorganisms by PCR-based methods.
    • Effect of rodent density on tick and tick-borne pathogen populations: consequences for infectious disease risk.

      Krawczyk, Aleksandra I; van Duijvendijk, Gilian L A; Swart, Arno; Heylen, Dieter; Jaarsma, Ryanne I; Jacobs, Frans H H; Fonville, Manoj; Sprong, Hein; Takken, Willem (2020-01-20)
      In a natural woodland, we manipulated rodent densities in plots of 2500 m2 by either supplementing a critical food source (acorns) or by removing rodents during two years. Untreated plots were used as controls. Collected nymphs and rodent ear biopsies were tested for the presence of seven tick-borne microorganisms. Linear models were used to capture associations between rodents, nymphs, and pathogens.
    • Hedgehogs and Squirrels as Hosts of Zoonotic Species.

      Majerová, Karolina; Gutiérrez, Ricardo; Fonville, Manoj; Hönig, Václav; Papežík, Petr; Hofmannová, Lada; Lesiczka, Paulina Maria; Nachum-Biala, Yaarit; Růžek, Daniel; Sprong, Hein; et al. (2021-06-01)
      Free-living animals frequently play a key role in the circulation of various zoonotic vector-borne pathogens. Bacteria of the genus Bartonella are transmitted by blood-feeding arthropods and infect a large range of mammals. Although only several species have been identified as causative agents of human disease, it has been proposed that any Bartonella species found in animals may be capable of infecting humans. Within a wide-ranging survey in various geographical regions of the Czech Republic, cadavers of accidentally killed synurbic mammalian species, namely Eurasian red squirrel (Sciurus vulgaris), European hedgehog (Erinaceus europaeus) and Northern white-breasted hedgehog (Erinaceus roumanicus), were sampled and tested for Bartonella presence using multiple PCR reaction approach targeting several DNA loci. We demonstrate that cadavers constitute an available and highly useful source of biological material for pathogen screening. High infection rates of Bartonella spp., ranging from 24% to 76%, were confirmed for all three tested mammalian species, and spleen, ear, lung and liver tissues were demonstrated as the most suitable for Bartonella DNA detection. The wide spectrum of Bartonella spp. that were identified includes three species with previously validated zoonotic potential, B. grahamii, B. melophagi and B. washoensis, accompanied by 'Candidatus B. rudakovii' and two putative novel species, Bartonella sp. ERIN and Bartonella sp. SCIER.
    • Hedgehogs, Squirrels, and Blackbirds as Sentinel Hosts for Active Surveillance of and Complex in Urban and Rural Environments.

      Majerová, Karolina; Hönig, Václav; Houda, Michal; Papežík, Petr; Fonville, Manoj; Sprong, Hein; Rudenko, Natalie; Golovchenko, Maryna; Černá Bolfíková, Barbora; Hulva, Pavel; et al. (2020-11-30)
      Lyme borreliosis (LB), caused by spirochetes of the Borrelia burgdorferi sensu lato (s.l.) complex, is one of the most common vector-borne zoonotic diseases in Europe. Knowledge about the enzootic circulation of Borrelia pathogens between ticks and their vertebrate hosts is epidemiologically important and enables assessment of the health risk for the human population. In our project, we focused on the following vertebrate species: European hedgehog (Erinaceus europaeus), Northern white-breasted hedgehog (E. roumanicus), Eurasian red squirrel (Sciurus vulgaris), and Common blackbird (Turdus merula). The cadavers of accidentally killed animals used in this study constitute an available source of biological material, and we have confirmed its potential for wide monitoring of B. burgdorferi s.l. presence and genospecies diversity in the urban environment. High infection rates (90% for E. erinaceus, 73% for E. roumanicus, 91% for S. vulgaris, and 68% for T. merula) were observed in all four target host species; mixed infections by several genospecies were detected on the level of individuals, as well as in particular tissue samples. These findings show the usefulness of multiple tissue sampling as tool for revealing the occurrence of several genospecies within one animal and the risk of missing particular B. burgdorferi s.l. genospecies when looking in one organ alone.
    • Longitudinal analysis of tick densities and Borrelia, Anaplasma, and Ehrlichia infections of Ixodes ricinus ticks in different habitat areas in The Netherlands.

      Wielinga, Peter R; Gaasenbeek, Cor; Fonville, Manoj; Boer, Albert de; Vries, Ankje de; Dimmers, Wim; Akkerhuis Op Jagers, Gerard; Schouls, Leo M; Borgsteede, Fred; Giessen, Joke W B van der (2006-12-01)
      From 2000 to 2004, ticks were collected by dragging a blanket in four habitat areas in The Netherlands: dunes, heather, forest, and a city park. Tick densities were calculated, and infection with Borrelia burgdorferi and Anaplasma and Ehrlichia species was investigated by reverse line blot analysis. The lowest tick density was observed in the heather area (1 to 8/100 m2). In the oak forest and city park, the tick densities ranged from 26 to 45/100 m2. The highest tick density was found in the dune area (139 to 551/100 m2). The infection rates varied significantly for the four study areas and years, ranging from 0.8 to 11. 5% for Borrelia spp. and 1 to 16% for Ehrlichia or Anaplasma (Ehrlichia/Anaplasma) spp. Borrelia infection rates were highest in the dunes, followed by the forest, the city park, and heather area. In contrast, Ehrlichia/Anaplasma was found most often in the forest and less often in the city park. The following Borrelia species were found: Borrelia sensu lato strains not identified to the species level (2.5%), B. afzelii (2.5%), B. valaisiana (0.9%), B. burgdorferi sensu stricto (0.13%), and B. garinii (0.13%). For Ehrlichia/Anaplasma species, Ehrlichia and Anaplasma spp. not identified to the species level (2.5%), Anaplasma schotti variant (3.5%), Anaplasma phagocytophilum variant (0.3%), and Ehrlichia canis (0.19%) were found. E. canis is reported for the first time in ticks in The Netherlands in this study. Borrelia lusitaniae, Ehrlichia chaffeensis, and the human granylocytic anaplasmosis agent were not detected. About 1.6% of the ticks were infected with both Borrelia and Ehrlichia/Anaplasma, which was higher than the frequency predicted from the individual infection rates, suggesting hosts with multiple infections or a possible selective advantage of coinfection.
    • Mitochondrial sequences of Rhipicephalus and Coxiella endosymbiont reveal evidence of lineages co-cladogenesis.

      Coimbra-Dores, Maria João; Jaarsma, Ryanne Isolde; Carmo, Anderson Oliveira; Maia-Silva, Mariana; Fonville, Manoj; da Costa, Daniela Filipa Ferreira; Brandão, Ricardo Manuel Lemos; Azevedo, Fábia; Casero, María; Oliveira, Ana Cristina; et al. (2020-06-01)
    • Occurrence of tick-borne pathogens in questing Ixodes ricinus ticks from Wester Ross, Northwest Scotland.

      Olsthoorn, Fanny; Sprong, Hein; Fonville, Manoj; Rocchi, Mara; Medlock, Jolyon; Gilbert, Lucy; Ghazoul, Jaboury (2021-08-26)
    • Pathogen communities of songbird-derived ticks in Europe's low countries.

      Heylen, Dieter; Fonville, Manoj; Docters van Leeuwen, Arieke; Stroo, Arjan; Duisterwinkel, Martin; van Wieren, Sip; Diuk-Wasser, Maria; de Bruin, Arnout; Sprong, Hein (2017-10-18)
      Birds play a major role in the maintenance of enzootic cycles of pathogens transmitted by ticks. Due to their mobility, they affect the spatial distribution and abundance of both ticks and pathogens. In the present study, we aim to identify members of a pathogen community [Borrelia burgdorferi (s.l.), B. miyamotoi, 'Ca. Neoehrlichia mikurensis', Anaplasma phagocytophilum and Rickettsia helvetica] in songbird-derived ticks from 11 locations in the Netherlands and Belgium (2012-2014).
    • Prevalence of pathogens in ticks collected from humans through citizen science in Belgium.

      Lernout, Tinne; De Regge, Nick; Tersago, Katrien; Fonville, Manoj; Suin, Vanessa; Sprong, Hein (2019-11-21)
    • Role of mustelids in the life-cycle of ixodid ticks and transmission cycles of four tick-borne pathogens.

      Hofmeester, Tim R; Krawczyk, Aleksandra I; van Leeuwen, Arieke Docters; Fonville, Manoj; Montizaan, Margriet G E; van den Berge, Koen; Gouwy, Jan; Ruyts, Sanne C; Verheyen, Kris; Sprong, Hein (2018-11-20)
      Elucidating which wildlife species significantly contribute to the maintenance of Ixodes ricinus populations and the enzootic cycles of the pathogens they transmit is imperative in understanding the driving forces behind the emergence of tick-borne diseases. Here, we aimed to quantify the relative contribution of four mustelid species in the life-cycles of I. ricinus and Borrelia burgdorferi (sensu lato) in forested areas and to investigate their role in the transmission of other tick-borne pathogens. Road-killed badgers, pine martens, stone martens and polecats were collected in Belgium and the Netherlands. Their organs and feeding ticks were tested for the presence of tick-borne pathogens. Ixodes hexagonus and I. ricinus were found on half of the screened animals (n = 637). Pine martens had the highest I. ricinus burden, whereas polecats had the highest I. hexagonus burden. We detected DNA from B. burgdorferi (s.l.) and Anaplasma phagocytophilum in organs of all four mustelid species (n = 789), and Neoehrlichia mikurensis DNA was detected in all species, except badgers. DNA from B. miyamotoi was not detected in any of the investigated mustelids. From the 15 larvae of I. ricinus feeding on pine martens (n = 44), only one was positive for B. miyamotoi DNA, and all tested negative for B. burgdorferi (s.l.), N. mikurensis and A. phagocytophilum. The two feeding larvae from the investigated polecats (n = 364) and stone martens (n = 39) were negative for all four pathogens. The infection rate of N. mikurensis was higher in feeding nymphs collected from mustelids compared to questing nymphs, but not for B. burgdorferi (s.l.), B. miyamotoi or A. phagocytophilum. Although all stages of I. ricinus can be found on badgers, polecats, pine and stone martens, their relative contribution to the life-cycle of I. ricinus in forested areas is less than 1%. Consequently, the relative contribution of mustelids to the enzootic cycles of I. ricinus-borne pathogens is negligible, despite the presence of these pathogens in organs and feeding ticks. Interestingly, all four mustelid species carried all stages of I. hexagonus, potentially maintaining enzootic cycles of this tick species apart from the cycle involving hedgehogs as main host species.
    • The Role of Peridomestic Animals in the Eco-Epidemiology of Anaplasma phagocytophilum.

      Lesiczka, Paulina Maria; Hrazdilová, Kristýna; Majerová, Karolina; Fonville, Manoj; Sprong, Hein; Hönig, Václav; Hofmannová, Lada; Papežík, Petr; Růžek, Daniel; Zurek, Ludek; et al. (2021-02-05)
    • Seasonal patterns and spatial variation of Borrelia burgdorferi (sensu lato) infections in Ixodes ricinus in the Netherlands.

      Hartemink, Nienke; van Vliet, Arnold J H; Gort, Gerrit; Gassner, Fedor; Jacobs, Frans; Fonville, Manoj; Takken, Willem; Sprong, Hein (2021-02-24)
    • Seoul Virus in Pet and Feeder Rats in The Netherlands.

      Cuperus, Tryntsje; de Vries, Ankje; Hoornweg, Tabitha E; Fonville, Manoj; Jaarsma, Ryanne I; Opsteegh, Marieke; Maas, Miriam (2021-03-10)
      Seoul virus (SEOV) is a zoonotic orthohantavirus carried by rats. In humans, SEOV can cause hemorrhagic fever with renal syndrome. Recent human SEOV cases described in the USA, United Kingdom, France and the Netherlands were associated with contact with pet or feeder rats. The prevalence of SEOV in these types of rats is unknown. We collected 175 pet and feeder rats (Rattus norvegicus) from private owners, ratteries and commercial breeders/traders in the Netherlands. Lung tissue of the rats was tested using a SEOV real-time RT-qPCR and heart fluid was tested for the presence of antibodies against SEOV. In all three investigated groups, RT-qPCR-positive rats were found: in 1/29 rats from private owners (3.6%), 2/56 rats from ratteries (3.4%) and 11/90 rats from commercial breeders (12.2%). The seroprevalence was largely similar to the prevalence calculated from RT-qPCR-positive rats. The SEOV sequences found were highly similar to sequences previously found in domesticated rats in Europe. In conclusion, SEOV is spread throughout different populations of domesticated rats.
    • Tripartite Interactions among , and Deer: Differential Interference with Transmission Cycles of Tick-Borne Pathogens.

      Krawczyk, Aleksandra I; Bakker, Julian W; Koenraadt, Constantianus J M; Fonville, Manoj; Takumi, Katsuhisa; Sprong, Hein; Demir, Samiye (2020-04-30)
      For the development of sustainable control of tick-borne diseases, insight is needed in biological factors that affect tick populations. Here, the ecological interactions among Ixodiphagus hookeri, Ixodes ricinus, and two vertebrate species groups were investigated in relation to their effects on tick-borne disease risk. In 1129 questing ticks, I. hookeri DNA was detected more often in I. ricinus nymphs (4.4%) than in larvae (0.5%) and not in adults. Therefore, we determined the infestation rate of I. hookeri in nymphs from 19 forest sites, where vertebrate, tick, and tick-borne pathogen communities had been previously quantified. We found higher than expected co-occurrence rates of I. hookeri with deer-associated Anaplasma phagocytophilum, and lower than expected rates with rodent-associated Borrelia afzelii and Neoehrlichia mikurensis. The prevalence of I. hookeri in nymphs varied between 0% and 16% and was positively correlated with the encounter probability of ungulates and the densities of all life stages of I. ricinus. Lastly, we investigated the emergence of I. hookeri from artificially fed, field-collected nymphs. Adult wasps emerged from seven of the 172 fed nymphs. From these observations, we inferred that I. hookeri is parasitizing I. ricinus larvae that are feeding on deer, rather than on rodents or in the vegetation. Since I. hookeri populations depend on deer abundance, the main propagation host of I. ricinus, these wasps have no apparent effect on tick populations. The presence of I. hookeri may directly interfere with the transmission cycle of A. phagocytophilum, but not with that of B. afzelii or N. mikurensis.