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Dong R, Fang R, Yang X, Sun Y, Zhang Y, Li S. An Updated Review on the Spatial Distribution of Borrelia burgdorferi Sensu Lato Across Ticks, Animals and Humans in Northeastern China and Adjacent Regions. Zoonoses Public Health 2024. [PMID: 39148261 DOI: 10.1111/zph.13176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 07/19/2024] [Accepted: 08/03/2024] [Indexed: 08/17/2024]
Abstract
BACKGROUND Lyme disease is a tick-borne zoonotic disease caused by Borrelia burgdorferi sensu lato and is prevalent in northeastern Asia, particularly in the forested area of Northeastern China. However, a lack of systematic data on the spatial distribution of B. burgdorferi in this region hinders the prediction of its transmission risk across the landscape. METHODS To provide an updated overview and establish a comprehensive spatial distribution database, we conducted a systematic review of literature published between 2000 and 2022. We collected and compiled relevant data on B. burgdorferi in Northeastern China and its neighbouring regions, outlining its distribution in ticks, wild animals, livestock and humans. Spatial analysis was performed to identify spatial clusters of tick positivity and host infection rates. RESULTS From a total of 1823 literature, we selected 110 references to compile 626 detection records of B. burgdorferi, including 288 in ticks, 109 in wildlife, 111 in livestock and domestic animals and 100 in humans. The average detection rate of B. burgdorferi in ticks was approximately 20%, with wildlife, livestock and domestic animal host positivity rates below 50% and human seroprevalence rates varying from 0.94% to 44.18%. CONCLUSIONS The study identified the presence of 17 tick species and ten genotypes of B. burgdorferi in the region, indicating a broad distribution. Notably, B. burgdorferi exhibited notable clustering, particularly in the central and eastern areas of Jilin Province, warranting further investigation.
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Affiliation(s)
- Ruixuan Dong
- College of Science, National University of Defense Technology, Changsha, China
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Ruying Fang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Xin Yang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Yifan Sun
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Yinsheng Zhang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Sen Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
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Mols B, Churchill JE, Cromsigt JPGM, Kuijper DPJ, Smit C. Recreation reduces tick density through fine-scale risk effects on deer space-use. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 839:156222. [PMID: 35623530 DOI: 10.1016/j.scitotenv.2022.156222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 04/28/2022] [Accepted: 05/21/2022] [Indexed: 06/15/2023]
Abstract
Altered interactions between pathogens, their hosts and vectors have potential consequences for human disease risk. Notably, tick-borne pathogens, many of which are associated with growing deer abundance, show global increasing prevalence and pose increasing challenges for disease prevention. Human activities can largely affect the patterns of deer space-use and can therefore be potential management tools to alleviate human-wildlife conflicts. Here, we tested how deer space-use patterns are influenced by human recreational activities, and how this in turn affects the spatial distribution of the sheep tick (Ixodes ricinus), a relevant disease vector of zoonoses such as Lyme borrelioses. We compared deer dropping and questing tick density on transects near (20 m) and further away from (100 m) forest trails that were either frequently used (open for recreation) or infrequently used (closed for recreation, but used by park managers). In contrast to infrequently used trails, deer dropping density was 31% lower near (20 m) than further away from (100 m) frequently used trails. Similarly, ticks were 62% less abundant near (20 m) frequently used trails compared to further away from (100 m) these trails, while this decline in tick numbers was only 14% near infrequently used trails. The avoidance by deer of areas close to human-used trails was thus associated with a similar reduction in questing tick density near these trails. As tick abundance generally correlates to pathogen prevalence, the use of trails for recreation may reduce tick-borne disease risk for humans on and near these trails. Our study reveals an unexplored effect of human activities on ecosystems and how this knowledge could be potentially used to mitigate zoonotic disease risk.
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Affiliation(s)
- B Mols
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands.
| | - J E Churchill
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - J P G M Cromsigt
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden; Centre for African Conservation Ecology, Department of Zoology, Nelson Mandela University, 6031 Gqeberha, South Africa
| | - D P J Kuijper
- Mammal Research Institute, Polish Academy of Sciences, Ul. Stoczek 1, 17-230 Białowieża, Poland
| | - C Smit
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
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Lejal E, Chiquet J, Aubert J, Robin S, Estrada-Peña A, Rue O, Midoux C, Mariadassou M, Bailly X, Cougoul A, Gasqui P, Cosson JF, Chalvet-Monfray K, Vayssier-Taussat M, Pollet T. Temporal patterns in Ixodes ricinus microbial communities: an insight into tick-borne microbe interactions. MICROBIOME 2021; 9:153. [PMID: 34217365 PMCID: PMC8254910 DOI: 10.1186/s40168-021-01051-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 03/17/2021] [Indexed: 06/01/2023]
Abstract
BACKGROUND Ticks transmit pathogens of medical and veterinary importance and are an increasing threat to human and animal health. Assessing disease risk and developing new control strategies requires identifying members of the tick-borne microbiota as well as their temporal dynamics and interactions. METHODS Using high-throughput sequencing, we studied the Ixodes ricinus microbiota and its temporal dynamics. 371 nymphs were monthly collected during three consecutive years in a peri-urban forest. After a Poisson lognormal model was adjusted to our data set, a principal component analysis, sparse network reconstruction, and differential analysis allowed us to assess seasonal and monthly variability of I. ricinus microbiota and interactions within this community. RESULTS Around 75% of the detected sequences belonged to five genera known to be maternally inherited bacteria in arthropods and to potentially circulate in ticks: Candidatus Midichloria, Rickettsia, Spiroplasma, Arsenophonus and Wolbachia. The structure of the I. ricinus microbiota varied over time with interannual recurrence and seemed to be mainly driven by OTUs commonly found in the environment. Total network analysis revealed a majority of positive partial correlations. We identified strong relationships between OTUs belonging to Wolbachia and Arsenophonus, evidence for the presence of the parasitoid wasp Ixodiphagus hookeri in ticks. Other associations were observed between the tick symbiont Candidatus Midichloria and pathogens belonging to Rickettsia. Finally, more specific network analyses were performed on TBP-infected samples and suggested that the presence of pathogens belonging to the genera Borrelia, Anaplasma and Rickettsia may disrupt microbial interactions in I. ricinus. CONCLUSIONS We identified the I. ricinus microbiota and documented marked shifts in tick microbiota dynamics over time. Statistically, we showed strong relationships between the presence of specific pathogens and the structure of the I. ricinus microbiota. We detected close links between some tick symbionts and the potential presence of either pathogenic Rickettsia or a parasitoid in ticks. These new findings pave the way for the development of new strategies for the control of ticks and tick-borne diseases. Video abstract.
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Affiliation(s)
- E Lejal
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - J Chiquet
- Université Paris-Saclay, AgroParisTech, INRAE, UMR MIA-Paris, 75005, Paris, France
| | - J Aubert
- Université Paris-Saclay, AgroParisTech, INRAE, UMR MIA-Paris, 75005, Paris, France
| | - S Robin
- Université Paris-Saclay, AgroParisTech, INRAE, UMR MIA-Paris, 75005, Paris, France
| | - A Estrada-Peña
- Faculty of Veterinary Medicine, University of Zaragoza, Zaragoza, Spain
| | - O Rue
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
- INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Université Paris-Saclay, Jouy-en-Josas, France
| | - C Midoux
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
- INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Université Paris-Saclay, Jouy-en-Josas, France
- INRAE, PROSE, Université Paris-Saclay, Antony, France
| | - M Mariadassou
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
- INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Université Paris-Saclay, Jouy-en-Josas, France
| | - X Bailly
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR EPIA, 63122, Saint Genes Champanelle, France
- Université de Lyon, INRAE, VetAgro Sup, UMR EPIA, 69280, Marcy l'Etoile, France
| | - A Cougoul
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR EPIA, 63122, Saint Genes Champanelle, France
- Université de Lyon, INRAE, VetAgro Sup, UMR EPIA, 69280, Marcy l'Etoile, France
| | - P Gasqui
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR EPIA, 63122, Saint Genes Champanelle, France
- Université de Lyon, INRAE, VetAgro Sup, UMR EPIA, 69280, Marcy l'Etoile, France
| | - J F Cosson
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - K Chalvet-Monfray
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR EPIA, 63122, Saint Genes Champanelle, France
- Université de Lyon, INRAE, VetAgro Sup, UMR EPIA, 69280, Marcy l'Etoile, France
| | | | - T Pollet
- UMR ASTRE, CIRAD, INRAE, Campus de Baillarguet, Montpellier, France.
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Seasonal patterns and spatial variation of Borrelia burgdorferi (sensu lato) infections in Ixodes ricinus in the Netherlands. Parasit Vectors 2021; 14:121. [PMID: 33627166 PMCID: PMC7905678 DOI: 10.1186/s13071-021-04607-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/23/2021] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND The incidence of Lyme borreliosis varies over time and space through as yet incompletely understood mechanisms. In Europe, Lyme borreliosis is caused by infection with a Borrelia burgdorferi (s.l.) genospecies, which is primarily transmitted by a bite of Ixodes ricinus nymphs. The aim of this study was to investigate the spatial and temporal variation in nymphal infection prevalence of B. burgdorferi (s.l.) (NIP), density of questing nymphs (DON) and the resulting density of infected nymphs (DIN). METHODS We investigated the infection rates in I. ricinus nymphs that were collected monthly between 2009 and 2016 in 12 locations in the Netherlands. Using generalized linear mixed models, we explored how the NIP, DON and DIN varied during the seasons, between years and between locations. We also determined the genospecies of the Borrelia infections and investigated whether the genospecies composition differed between locations. RESULTS The overall NIP was 14.7%. A seasonal pattern in infection prevalence was observed, with higher estimated prevalences in the summer than in the spring and autumn. This, combined with higher nymphal densities in summer, resulted in a pronounced summer peak in the estimated DIN. Over the 7.5-year study period, a significant decrease in infection prevalence was found, as well as a significant increase in nymphal density. These two effects appear to cancel each other out; the density of infected nymphs, which is the product of NIP × DON, showed no significant trend over years. Mean infection prevalence (NIP, averaged over all years and all months) varied considerably between locations, ranging from 5 to 26%. Borrelia genospecies composition differed between locations: in some locations almost all infections consisted of B. afzelii, whereas other locations had more diverse genospecies compositions. CONCLUSION In the Netherlands, the summer peak in DIN is a result of peaks in both NIP and DON. No significant trend in DIN was observed over the years of the study, and variations in DIN between locations were mostly a result of the variation in DON. There were considerable differences in acarological risk between areas in terms of infection prevalence and densities of ticks as well as in Borrelia genospecies composition.
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Bonnet SI, Pollet T. Update on the intricate tango between tick microbiomes and tick-borne pathogens. Parasite Immunol 2020; 43:e12813. [PMID: 33314216 DOI: 10.1111/pim.12813] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022]
Abstract
The recent development of high-throughput NGS technologies, (ie, next-generation sequencing) has highlighted the complexity of tick microbial communities-which include pathogens, symbionts, and commensals-and also their dynamic variability. Symbionts and commensals can confer crucial and diverse benefits to their hosts, playing nutritional roles or affecting fitness, development, nutrition, reproduction, defence against environmental stress and immunity. Nonpathogenic tick bacteria may also play a role in modifying tick-borne pathogen colonization and transmission, as relationships between microorganisms existing together in one environment can be competitive, exclusive, facilitating or absent, with many potential implications for both human and animal health. Consequently, ticks represent a compelling yet challenging system in which to investigate the composition and both the functional and ecological implications of tick bacterial communities, and thus merits greater attention. Ultimately, deciphering the relationships between microorganisms carried by ticks as well as symbiont-tick interactions will garner invaluable information, which may aid in some future arthropod-pest and vector-borne pathogen transmission control strategies. This review outlines recent research on tick microbiome composition and dynamics, highlights elements favouring the reciprocal influence of the tick microbiome and tick-borne agents and finally discusses how ticks and tick-borne diseases might potentially be controlled through tick microbiome manipulation in the future.
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Affiliation(s)
- Sarah Irène Bonnet
- UMR BIPAR 0956, INRAE, Ecole Nationale Vétérinaire d'Alfort, ANSES, Université Paris-Est, Maisons-Alfort, France
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Pollet T, Sprong H, Lejal E, Krawczyk AI, Moutailler S, Cosson JF, Vayssier-Taussat M, Estrada-Peña A. The scale affects our view on the identification and distribution of microbial communities in ticks. Parasit Vectors 2020; 13:36. [PMID: 31964404 PMCID: PMC6975024 DOI: 10.1186/s13071-020-3908-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/15/2020] [Indexed: 01/25/2023] Open
Abstract
Ticks transmit the highest variety of pathogens impacting human and animal health worldwide. It is now well established that ticks also harbour a microbial complex of coexisting symbionts, commensals and pathogens. With the development of high throughput sequencing technologies, studies dealing with such diverse bacterial composition in tick considerably increased in the past years and revealed an unexpected microbial diversity. These data on diversity and composition of the tick microbes are increasingly available, giving crucial details on microbial communities in ticks and improving our knowledge on the tick microbial community. However, consensus is currently lacking as to which scales (tick organs, individual specimens or species, communities of ticks, populations adapted to particular environmental conditions, spatial and temporal scales) best facilitate characterizing microbial community composition of ticks and understanding the diverse relationships among tick-borne bacteria. Temporal or spatial scales have a clear influence on how we conduct ecological studies, interpret results, and understand interactions between organisms that build the microbiome. We consider that patterns apparent at one scale can collapse into noise when viewed from other scales, indicating that processes shaping tick microbiome have a continuum of variability that has not yet been captured. Based on available reports, this review demonstrates how much the concept of scale is crucial to be considered in tick microbial community studies to improve our knowledge on tick microbe ecology and pathogen/microbiota interactions.
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Affiliation(s)
- Thomas Pollet
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France.
| | - Hein Sprong
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Emilie Lejal
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Aleksandra I Krawczyk
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
- Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, The Netherlands
| | - Sara Moutailler
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Jean-Francois Cosson
- UMR BIPAR, Animal Health Laboratory, INRAE, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
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Krawczyk AI, van Duijvendijk GLA, Swart A, Heylen D, Jaarsma RI, Jacobs FHH, Fonville M, Sprong H, Takken W. Effect of rodent density on tick and tick-borne pathogen populations: consequences for infectious disease risk. Parasit Vectors 2020; 13:34. [PMID: 31959217 PMCID: PMC6971888 DOI: 10.1186/s13071-020-3902-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 01/08/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Rodents are considered to contribute strongly to the risk of tick-borne diseases by feeding Ixodes ricinus larvae and by acting as amplifying hosts for pathogens. Here, we tested to what extent these two processes depend on rodent density, and for which pathogen species rodents synergistically contribute to the local disease risk, i.e. the density of infected nymphs (DIN). METHODS 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. RESULTS Investigation of data from all plots, irrespective of the treatment, revealed a strong positive association between rodent density and nymphal density, nymphal infection prevalence (NIP) with Borrelia afzelii and Neoehrlichia mikurensis, and hence DIN's of these pathogens in the following year. The NIP, but not the DIN, of the bird-associated Borrelia garinii, decreased with increasing rodent density. The NIPs of Borrelia miyamotoi and Rickettsia helvetica were independent of rodent density, and increasing rodent density moderately increased the DINs. In addition, NIPs of Babesia microti and Spiroplasma ixodetis decreased with increasing rodent density, which had a non-linear association with DINs of these microorganisms. CONCLUSIONS A positive density dependence for all rodent- and tick-associated tick-borne pathogens was found, despite the observation that some of them decreased in prevalence. The effects on the DINs were variable among microorganisms, more than likely due to contrasts in their biology (including transmission modes, host specificity and transmission efficiency). The strongest associations were found in rodent-associated pathogens that most heavily rely on horizontal transmission. Our results draw attention to the importance of considering transmission mode of a pathogen while developing preventative measures to successfully reduce the burden of disease.
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Affiliation(s)
- Aleksandra I Krawczyk
- Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, The Netherlands. .,Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA, Bilthoven, The Netherlands.
| | | | - Arno Swart
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA, Bilthoven, The Netherlands
| | - Dieter Heylen
- Interuniversity Institute for Biostatistics and statistical Bioinformatics, Hasselt University, Diepenbeek, Belgium.,Department of Ecology and Evolutionary Biology, Princeton University, 106A Guyot Ln, Princeton, NJ, 08544, USA
| | - Ryanne I Jaarsma
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA, Bilthoven, The Netherlands
| | - Frans H H Jacobs
- Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, The Netherlands
| | - Manoj Fonville
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA, Bilthoven, The Netherlands
| | - Hein Sprong
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA, Bilthoven, The Netherlands.
| | - Willem Takken
- Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, The Netherlands
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Lejal E, Marsot M, Chalvet-Monfray K, Cosson JF, Moutailler S, Vayssier-Taussat M, Pollet T. A three-years assessment of Ixodes ricinus-borne pathogens in a French peri-urban forest. Parasit Vectors 2019; 12:551. [PMID: 31752997 PMCID: PMC6873405 DOI: 10.1186/s13071-019-3799-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/10/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Ixodes ricinus is the predominant tick species in Europe and the primary pathogen vector for both humans and animals. These ticks are frequently involved in the transmission of Borrelia burgdorferi (sensu lato), the causative agents of Lyme borreliosis. While much more is known about I. ricinus tick-borne pathogen composition, information about temporal tick-borne pathogen patterns remain scarce. These data are crucial for predicting seasonal/annual patterns which could improve understanding and prevent tick-borne diseases. METHODS We examined tick-borne pathogen (TBP) dynamics in I. ricinus collected monthly in a peri-urban forest over three consecutive years. In total, 998 nymphs were screened for 31 pathogenic species using high-throughput microfluidic real-time PCR. RESULTS We detected DNA from Anaplasma phagocytophilum (5.3%), Rickettsia helvetica (4.5%), Borrelia burgdorferi (s.l.) (3.7%), Borrelia miyamotoi (1.2%), Babesia venatorum (1.5%) and Rickettsia felis (0.1%). Among all analysed ticks, 15.9% were infected by at least one of these microorganisms, and 1.3% were co-infected. Co-infections with B. afzeli/B. garinii and B. garinii/B. spielmanii were significantly over-represented. Moreover, significant variations in seasonal and/or inter-annual prevalence were observed for several pathogens (R. helvetica, B. burgdorferi (s.l.), B. miyamotoi and A. phagocytophilum). CONCLUSIONS Analysing TBP prevalence in monthly sampled tick over three years allowed us to assess seasonal and inter-annual fluctuations of the prevalence of TBPs known to circulate in the sampled area, but also to detect less common species. All these data emphasize that sporadic tick samplings are not sufficient to determine TBP prevalence and that regular monitoring is necessary.
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Affiliation(s)
- Emilie Lejal
- UMR BIPAR, Animal Health Laboratory, INRA, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Maud Marsot
- Laboratory for Animal Health, Epidemiology Unit, ANSES, University Paris Est, Maisons-Alfort, France
| | - Karine Chalvet-Monfray
- UMR EPIA, VetAgro Sup, INRA, Université de Lyon, Université Clermont Auvergne, 63122 Saint-Genès-Champanelle, France
| | - Jean-François Cosson
- UMR BIPAR, Animal Health Laboratory, INRA, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Sara Moutailler
- UMR BIPAR, Animal Health Laboratory, INRA, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
| | | | - Thomas Pollet
- UMR BIPAR, Animal Health Laboratory, INRA, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
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Lernout T, De Regge N, Tersago K, Fonville M, Suin V, Sprong H. Prevalence of pathogens in ticks collected from humans through citizen science in Belgium. Parasit Vectors 2019; 12:550. [PMID: 31752967 PMCID: PMC6873681 DOI: 10.1186/s13071-019-3806-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/12/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND In order to evaluate the risk of human exposure to tick-borne pathogens in Belgium, a study on the prevalence of several pathogens was conducted on feeding ticks removed from humans in 2017. METHODS Using a citizen science approach based on an existing notification tool for tick bites, a sample of ticks was collected across the country. Collected ticks were screened by PCR for the presence of the following pathogens: Anaplasma phagocytophilum, Babesia spp., Borrelia burgdorferi (sensu lato), Borrelia miyamotoi, Neoehrlichia mikurensis, Rickettsia helvetica and tick-borne encephalitis virus (TBEV). RESULTS In total, 1599 ticks were included in the sample. The great majority of ticks belonged to Ixodes ricinus (99%); other tick species were identified as Ixodes hexagonus (0.7%) and Dermacentor reticulatus (0.3%). Borrelia burgdorferi (s.l.) was detected in 14% of nymphs and adult ticks. Adult ticks (20%) were more likely to be infected than nymphs (12%). The most common genospecies were B. afzelii (52%) and B. garinii (21%). Except for TBEV, the other tick-borne pathogens studied were all detected in the tick sample, although at a lower prevalence: 1.5% for Babesia spp.; 1.8% for A. phagocytophilum; 2.4% for B. miyamotoi; 2.8% for N. mikurensis; and 6.8% for R. helvetica. Rickettsia raoultii, the causative agent of tick-borne lymphadenopathy, was identified for the first time in Belgium, in two out of five D. reticulatus ticks. Co-infections were found in 3.9% of the examined ticks. The most common co-infection was B. burgdorferi (s.l.) + N. mikurensis. CONCLUSIONS Although for most of the tick-borne diseases in Belgium, other than Lyme borreliosis, no or few cases of human infection are reported, the pathogens causing these diseases were all (except for TBEV) detected in the tick study sample. Their confirmed presence can help raise awareness among citizens and health professionals in Belgium on possible diseases other than Lyme borreliosis in patients presenting fever or other non-characteristic symptoms after a tick bite.
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Affiliation(s)
- Tinne Lernout
- Sciensano, Belgian Institute for Health, Brussels, Belgium
| | - Nick De Regge
- Sciensano, Belgian Institute for Health, Brussels, Belgium
| | | | - Manoj Fonville
- Centre for Infectious Disease Control, National Institute for Public Health and Environment (RIVM), Bilthoven, The Netherlands
| | - Vanessa Suin
- Sciensano, Belgian Institute for Health, Brussels, Belgium
| | - Hein Sprong
- Centre for Infectious Disease Control, National Institute for Public Health and Environment (RIVM), Bilthoven, The Netherlands
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Impact of vertebrate communities on Ixodes ricinus-borne disease risk in forest areas. Parasit Vectors 2019; 12:434. [PMID: 31492171 PMCID: PMC6731612 DOI: 10.1186/s13071-019-3700-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 09/03/2019] [Indexed: 11/18/2022] Open
Abstract
Background The density of questing ticks infected with tick-borne pathogens is an important parameter that determines tick-borne disease risk. An important factor determining this density is the availability of different wildlife species as hosts for ticks and their pathogens. Here, we investigated how wildlife communities contribute to tick-borne disease risk. The density of Ixodes ricinus nymphs infected with Borrelia burgdorferi (sensu lato), Borrelia miyamotoi, Neoehrlichia mikurensis and Anaplasma phagocytophilum among 19 forest sites were correlated to the encounter probability of different vertebrate hosts, determined by encounter rates as measured by (camera) trapping and mathematical modeling. Result We found that the density of any tick life stage was proportional to the encounter probability of ungulates. Moreover, the density of nymphs decreased with the encounter probability of hare, rabbit and red fox. The density of nymphs infected with the transovarially-transmitted B. miyamotoi increased with the density of questing nymphs and the encounter probability of bank vole. The density of nymphs infected with all other pathogens increased with the encounter probability of competent hosts: bank vole for Borrelia afzelii and N. mikurensis, ungulates for A. phagocytophilum and blackbird for Borrelia garinii and Borrelia valaisiana. The negative relationship we found was a decrease in the density of nymphs infected with B. garinii and B. valaisiana with the encounter probability of wood mouse. Conclusions Only a few animal species drive the densities of infected nymphs in forested areas. There, foxes and leporids have negative effects on tick abundance, and consequently on the density of infected nymphs. The abundance of competent hosts generally drives the abundances of their tick-borne pathogen. A dilution effect was only observed for bird-associated Lyme spirochetes.![]()
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11
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Detection of pathogens in Dermacentor reticulatus in northwestern Europe: evaluation of a high-throughput array. Heliyon 2019; 5:e01270. [PMID: 30891514 PMCID: PMC6401523 DOI: 10.1016/j.heliyon.2019.e01270] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 02/11/2019] [Accepted: 02/19/2019] [Indexed: 01/07/2023] Open
Abstract
Background The geographic distribution of Dermacentor reticulatus is expanding in Europe. Surveillance of this tick species and its pathogens is desirable, as it transmits pathogens of public and veterinary importance. A high-throughput real-time PCR-based array was used to screen 1.741 D. reticulatus ticks from Belgium, Germany, The Netherlands, and Great Britain for the presence of 28 tick-borne bacteria and twelve protozoan parasites. The presence of pathogen DNA was confirmed by conventional PCR followed by sequencing. Results The array detected the presence of DNA from Borrelia spp. (7%), B. afzelii (0.1%), B. garinii (0.1%), B. spielmanii (0.1%), B. miyamotoi (0.2%), Anaplasma marginale (0.1%), A. phagocytophilum (0.1%), Ehrlichia canis (2%), Rickettsia helvetica (0.2%), spotted fever group Rickettsia (9.6%), Francisella tularensis or Francisella-like endosymbionts (95%), Coxiella burnettii (0.1%), Babesia divergens (0.2%), B. canis (0.9%) B. vogeli (5.6%), and Theileria equi (0.1%). Only the presence of B. canis and spotted fever group Rickettsia could be confirmed by conventional PCR and sequencing. The spotted fever Rickettsia-positive samples were all identified as R. raoultii. Conclusions We successfully detected and determined the prevalence of B. canis and R. raoultii in D. reticulatus. An high-throughput array that allows fast and comprehensive testing of tick-borne pathogens is advantageous for surveillance and future epidemiological studies. The importance of thorough validation of real-time PCR-based assays and careful interpretation is evident.
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12
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Hartemink N, van Vliet A, Sprong H, Jacobs F, Garcia-Martí I, Zurita-Milla R, Takken W. Temporal-Spatial Variation in Questing Tick Activity in the Netherlands: The Effect of Climatic and Habitat Factors. Vector Borne Zoonotic Dis 2019; 19:494-505. [PMID: 30810501 DOI: 10.1089/vbz.2018.2369] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Longitudinal studies are fundamental in the assessment of the effect of environmental factors on tick population dynamics. In this study, we use data from a 10-year study in 11 different locations in the Netherlands to gauge the effects of climatic and habitat factors on the temporal and spatial variation in questing tick activity. Marked differences in the total number of ticks were found between locations and between years. We investigated which climatic and habitat factors might explain this variation. No effects of climatic factors on the total number of ticks per year were observed, but we found a clear effect of temperature on the onset of tick activity. In addition, we found positive associations between (1) humus layer thickness and densities of all three stages, (2) moss and blackberry abundance and larval densities, and (3) blueberry abundance and densities of larva and nymphs. We conclude that climatic variables do not have a straightforward association with tick density in the Netherlands, but that winter and spring temperatures influence the onset of tick activity. Habitats with apparently similar vegetation types can still differ in tick population densities, indicating that local composition of vegetation and especially of wildlife is likely to contribute considerably to the spatial variation in tick densities.
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Affiliation(s)
- Nienke Hartemink
- 1 Biometris, Wageningen University and Research Centre, Wageningen, the Netherlands.,2 Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, the Netherlands
| | - Arnold van Vliet
- 3 Environmental Systems Analysis Group, Wageningen University and Research Centre, Wageningen, the Netherlands
| | - Hein Sprong
- 2 Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, the Netherlands.,4 Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Frans Jacobs
- 2 Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, the Netherlands.,5 Centre for Vector Surveillance, Netherlands Food and Consumer Product Safety Authority, Wageningen, the Netherlands
| | - Irene Garcia-Martí
- 6 Royal Netherlands Meteorological Institute, De Bilt, the Netherlands.,7 Faculty of Geo-Information Science and Earth Observation, University of Twente, Enschede, the Netherlands
| | - Raul Zurita-Milla
- 7 Faculty of Geo-Information Science and Earth Observation, University of Twente, Enschede, the Netherlands
| | - Willem Takken
- 2 Laboratory of Entomology, Wageningen University and Research Centre, Wageningen, the Netherlands
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13
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Sormunen JJ, Klemola T, Hänninen J, Mäkelä S, Vuorinen I, Penttinen R, Sääksjärvi IE, Vesterinen EJ. The importance of study duration and spatial scale in pathogen detection-evidence from a tick-infested island. Emerg Microbes Infect 2018; 7:189. [PMID: 30482899 PMCID: PMC6258729 DOI: 10.1038/s41426-018-0188-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 09/24/2018] [Accepted: 10/21/2018] [Indexed: 12/11/2022]
Abstract
Ticks (Acari: Ixodoidea) are among the most common vectors of zoonotic pathogens worldwide. While research on tick-borne pathogens is abundant, few studies have thoroughly investigated small-scale spatial differences in their occurrence. Here, we used long-term cloth-dragging data of Ixodes ricinus and its associated, known and putative pathogens (Borrelia burgdorferi s.l., Borrelia miyamotoi, Anaplasma phagocytophilum, Rickettsia spp., Candidatus Neoehrlichia mikurensis, Bartonella spp., Babesia spp., and tick-borne encephalitis virus, TBEV) from a small, well-studied island in southwestern Finland to analyze potential temporal and spatial differences in pathogen prevalence and diversity between and within different biotopes. We found robust evidence indicating significant dissimilarities in B. burgdorferi s.l., A. phagocytophilum, Rickettsia, and Ca. N. mikurensis prevalence, even between proximal study areas on the island. Moreover, during the 6 years of the ongoing study, we witnessed the possible emergence of TBEV and Ca. N. mikurensis on the island. Finally, the stable occurrence of a protozoan pathogen that has not been previously reported in Finland, Babesia venatorum, was observed on the island. Our study underlines the importance of detailed, long-term tick surveys for public health. We propose that by more precisely identifying different environmental factors associated with the emergence and upkeep of enzootic pathogen populations through rigorous longitudinal surveys, we may be able to create more accurate models for both current and future pathogen distributions.
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Affiliation(s)
- Jani Jukka Sormunen
- Department of Biology, University of Turku, FI-20014, Turku, Finland. .,Biodiversity Unit, University of Turku, FI-20014, Turku, Finland.
| | - Tero Klemola
- Department of Biology, University of Turku, FI-20014, Turku, Finland
| | - Jari Hänninen
- Biodiversity Unit, University of Turku, FI-20014, Turku, Finland
| | - Satu Mäkelä
- Department of Biology, University of Turku, FI-20014, Turku, Finland
| | - Ilppo Vuorinen
- Biodiversity Unit, University of Turku, FI-20014, Turku, Finland
| | - Ritva Penttinen
- Biodiversity Unit, University of Turku, FI-20014, Turku, Finland
| | | | - Eero Juhani Vesterinen
- Biodiversity Unit, University of Turku, FI-20014, Turku, Finland.,Deparment of Agricultural Sciences, University of Helsinki, FI-00014, Helsinki, Finland
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14
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Hofmeester TR, Krawczyk AI, van Leeuwen AD, Fonville M, Montizaan MGE, van den Berge K, Gouwy J, Ruyts SC, Verheyen K, Sprong H. Role of mustelids in the life-cycle of ixodid ticks and transmission cycles of four tick-borne pathogens. Parasit Vectors 2018; 11:600. [PMID: 30458847 PMCID: PMC6245527 DOI: 10.1186/s13071-018-3126-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 09/28/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND 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. RESULTS 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. CONCLUSIONS 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.
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Affiliation(s)
- Tim R Hofmeester
- Resource Ecology Group, Wageningen University, Wageningen, the Netherlands. .,Present address: Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, 907 36, Umeå, Sweden.
| | - Aleksandra I Krawczyk
- Centre for Zoonoses and Environmental Microbiology, Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Arieke Docters van Leeuwen
- Centre for Zoonoses and Environmental Microbiology, Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Manoj Fonville
- Centre for Zoonoses and Environmental Microbiology, Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | | | - Koen van den Berge
- Research Institute for Nature and Forest (INBO), Geraardsbergen, Belgium
| | - Jan Gouwy
- Research Institute for Nature and Forest (INBO), Geraardsbergen, Belgium
| | - Sanne C Ruyts
- Forest and Nature Lab, Department of Environment, Ghent University, Geraardsbergsesteenweg 267, 9090, Gontrode, Melle, Belgium
| | - Kris Verheyen
- Forest and Nature Lab, Department of Environment, Ghent University, Geraardsbergsesteenweg 267, 9090, Gontrode, Melle, Belgium
| | - Hein Sprong
- Centre for Zoonoses and Environmental Microbiology, Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands.
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15
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Brugger K, Walter M, Chitimia-Dobler L, Dobler G, Rubel F. Forecasting next season's Ixodes ricinus nymphal density: the example of southern Germany 2018. EXPERIMENTAL & APPLIED ACAROLOGY 2018; 75:281-288. [PMID: 29846854 PMCID: PMC6097749 DOI: 10.1007/s10493-018-0267-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/18/2018] [Indexed: 05/13/2023]
Abstract
The castor bean tick, Ixodes ricinus (L.) (Ixodida: Ixodidae), is the principal vector of pathogens causing tick-borne encephalitis or Lyme borreliosis in Europe. It is therefore of general interest to make an estimate of the density of I. ricinus for the whole year at the beginning of the tick season. There are two necessary conditions for making a successful prediction: a long homogeneous time series of observed tick density and a clear biological relationship between environmental predictors and tick density. A 9-year time series covering the period 2009-2017 of nymphal I. ricinus flagged at monthly intervals in southern Germany has been used. With the hypothesis that I. ricinus density is triggered by the fructification of the European beech 2 years before, the mean annual temperature of the previous year, and the current mean winter temperature (December-February), a forecast of the annual nymphal tick density has been made. Therefore, a Poisson regression model was generated resulting in an explained variance of 93.4% and an error of [Formula: see text] ticks per [Formula: see text] (annual [Formula: see text] collected ticks/[Formula: see text]). An independent verification of the forecast for the year 2017 resulted in 187 predicted versus 180 observed nymphs per [Formula: see text]. For the year 2018 a relatively high number of 443 questing I. ricinus nymphs per [Formula: see text] is forecasted, i.e., a "good" tick year.
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Affiliation(s)
- Katharina Brugger
- Institute for Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria.
| | - Melanie Walter
- Institute for Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Lidia Chitimia-Dobler
- Bundeswehr Institute of Microbiology, Neuherbergstraße 11, 80937, Munich, Germany
- German Center of Infection Research (DZIF), Partner Site Munich, Munich, Germany
| | - Gerhard Dobler
- Bundeswehr Institute of Microbiology, Neuherbergstraße 11, 80937, Munich, Germany
- German Center of Infection Research (DZIF), Partner Site Munich, Munich, Germany
- Parasitology Unit, University of Hohenheim, Emil-Wolff-Straße 34, 70593, Stuttgart, Germany
| | - Franz Rubel
- Institute for Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
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16
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Rosà R, Andreo V, Tagliapietra V, Baráková I, Arnoldi D, Hauffe HC, Manica M, Rosso F, Blaňarová L, Bona M, Derdáková M, Hamšíková Z, Kazimírová M, Kraljik J, Kocianová E, Mahríková L, Minichová L, Mošanský L, Slovák M, Stanko M, Špitalská E, Ducheyne E, Neteler M, Hubálek Z, Rudolf I, Venclikova K, Silaghi C, Overzier E, Farkas R, Földvári G, Hornok S, Takács N, Rizzoli A. Effect of Climate and Land Use on the Spatio-Temporal Variability of Tick-Borne Bacteria in Europe. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15040732. [PMID: 29649132 PMCID: PMC5923774 DOI: 10.3390/ijerph15040732] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 03/29/2018] [Accepted: 04/10/2018] [Indexed: 11/29/2022]
Abstract
The incidence of tick-borne diseases caused by Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Rickettsia spp. has been rising in Europe in recent decades. Early pre-assessment of acarological hazard still represents a complex challenge. The aim of this study was to model Ixodes ricinus questing nymph density and its infection rate with B. burgdorferi s.l., A. phagocytophilum and Rickettsia spp. in five European countries (Italy, Germany, Czech Republic, Slovakia, Hungary) in various land cover types differing in use and anthropisation (agricultural, urban and natural) with climatic and environmental factors (Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Land Surface Temperature (LST) and precipitation). We show that the relative abundance of questing nymphs was significantly associated with climatic conditions, such as higher values of NDVI recorded in the sampling period, while no differences were observed among land use categories. However, the density of infected nymphs (DIN) also depended on the pathogen considered and land use. These results contribute to a better understanding of the variation in acarological hazard for Ixodes ricinus transmitted pathogens in Central Europe and provide the basis for more focused ecological studies aimed at assessing the effect of land use in different sites on tick–host pathogens interaction.
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Affiliation(s)
- Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Veronica Andreo
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
- Department of Earth Observation Science, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7500 AE Enschede, The Netherlands.
| | - Valentina Tagliapietra
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Ivana Baráková
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Daniele Arnoldi
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Heidi Christine Hauffe
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Mattia Manica
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Fausta Rosso
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
| | - Lucia Blaňarová
- Parasitological Institute, Slovak Academy of Sciences, 04001 Košice, Slovakia.
| | - Martin Bona
- Department of Anatomy, Pavol Jozef Šafárik University, 04001 Košice, Slovakia.
| | - Marketa Derdáková
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Zuzana Hamšíková
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Maria Kazimírová
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Jasna Kraljik
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Elena Kocianová
- Institute of Virology, Biomedical Research Center, Slovak Academy of Sciences, 84505 Bratislava, Slovakia.
| | - Lenka Mahríková
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Lenka Minichová
- Institute of Virology, Biomedical Research Center, Slovak Academy of Sciences, 84505 Bratislava, Slovakia.
| | - Ladislav Mošanský
- Parasitological Institute, Slovak Academy of Sciences, 04001 Košice, Slovakia.
| | - Mirko Slovák
- Institute of Zoology, Slovak Academy of Sciences, 84506 Bratislava, Slovakia.
| | - Michal Stanko
- Parasitological Institute, Slovak Academy of Sciences, 04001 Košice, Slovakia.
| | - Eva Špitalská
- Institute of Virology, Biomedical Research Center, Slovak Academy of Sciences, 84505 Bratislava, Slovakia.
| | - Els Ducheyne
- Avia-GIS, Risschotlei 33, 2980 Zoersel, Belgium.
| | | | - Zdenek Hubálek
- Institute of Vertebrate Biology, v.v.i., Academy of Sciences of the Czech Republic, 60365 Brno, Czech Republic.
| | - Ivo Rudolf
- Institute of Vertebrate Biology, v.v.i., Academy of Sciences of the Czech Republic, 60365 Brno, Czech Republic.
| | - Kristyna Venclikova
- Institute of Vertebrate Biology, v.v.i., Academy of Sciences of the Czech Republic, 60365 Brno, Czech Republic.
- Institute of Macromolecular Chemistry CAS, 16206 Prague 6, Czech Republic.
| | - Cornelia Silaghi
- Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität, 80802 Munich, Germany.
- Institute of Parasitology, National Centre for Vector Entomology, Vetsuisse-Faculty, University of Zurich, 8057 Zürich, Switzerland.
- Institute of Infectology, Friedrich-Loeffler-Institut, 17493 Greifswald, Germany.
| | - Evelyn Overzier
- Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität, 80802 Munich, Germany.
| | - Robert Farkas
- Department of Parasitology and Zoology, University of Veterinary Medicine, 1078 Budapest, Hungary.
| | - Gábor Földvári
- Department of Parasitology and Zoology, University of Veterinary Medicine, 1078 Budapest, Hungary.
| | - Sándor Hornok
- Department of Parasitology and Zoology, University of Veterinary Medicine, 1078 Budapest, Hungary.
| | - Nóra Takács
- Department of Parasitology and Zoology, University of Veterinary Medicine, 1078 Budapest, Hungary.
| | - Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38010 San Michele all'Adige, Italy.
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17
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Hofmeester TR, Jansen PA, Wijnen HJ, Coipan EC, Fonville M, Prins HHT, Sprong H, van Wieren SE. Cascading effects of predator activity on tick-borne disease risk. Proc Biol Sci 2018; 284:rspb.2017.0453. [PMID: 28724731 PMCID: PMC5543215 DOI: 10.1098/rspb.2017.0453] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/16/2017] [Indexed: 11/23/2022] Open
Abstract
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.
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Affiliation(s)
- Tim R Hofmeester
- Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands
| | - Patrick A Jansen
- Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands.,Center for Tropical Forest Science, Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panamá
| | - Hendrikus J Wijnen
- Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands.,Adaptation Physiology Group, Wageningen University and Research, De Elst 1, 6708 WD Wageningen, The Netherlands
| | - Elena C Coipan
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Manoj Fonville
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Herbert H T Prins
- Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands
| | - Hein Sprong
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Sipke E van Wieren
- Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands
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18
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Kowalec M, Szewczyk T, Welc-Falęciak R, Siński E, Karbowiak G, Bajer A. Ticks and the city - are there any differences between city parks and natural forests in terms of tick abundance and prevalence of spirochaetes? Parasit Vectors 2017; 10:573. [PMID: 29157278 PMCID: PMC5697153 DOI: 10.1186/s13071-017-2391-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/19/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Ixodes ricinus ticks are commonly encountered in either natural or urban areas, contributing to Lyme disease agents Borreliella [(Borrelia burgdorferi (sensu lato)] spp. and Borrelia miyamotoi enzootic cycles in cities. It is an actual problem whether urbanization affects pathogen circulation and therefore risk of infection. The aim of the study was to evaluate main tick-borne disease risk factors in natural, endemic areas of north-east (NE) Poland (Białowieża) and urban areas of central Poland (Warsaw), measuring tick abundance/density, prevalence of infection with spirochaetes and diversity of these pathogens in spring-early summer and late summer-autumn periods between 2012 and 2015. METHODS Questing I. ricinus ticks were collected from three urban sites in Warsaw, central Poland and three natural sites in Białowieża, NE Poland. A total of 2993 ticks were analyzed for the presence of Borreliella spp. and/or Borrelia miyamotoi DNA by PCR. Tick abundance was analyzed by General Linear Models (GLM). Prevalence and distribution of spirochaetes was analyzed by Maximum Likelihood techniques based on log-linear analysis of contingency tables (HILOGLINEAR). Species typing and molecular phylogenetic analysis based on the sequenced flaB marker were carried out. RESULTS Overall 4617 I. ricinus ticks were collected (2258 nymphs and 2359 adults). We report well established population of ticks in urban areas (10.1 ± 0.9 ticks/100 m2), as in endemic natural areas with higher mean tick abundance (16.5 ± 1.5 ticks/100 m2). Tick densities were the highest in spring-early summer in both types of areas. We observed no effect of the type of area on Borreliella spp. and B. miyamotoi presence in ticks, resulting in similar prevalence of spirochaetes in urban and natural areas [10.9% (95% CI: 9.7-12.2%) vs 12.4% (95% CI: 10.1-15.1%), respectively]. Prevalence of spirochaetes was significantly higher in the summer-autumn period than in the spring-early summer [15.0% (95% CI: 12.8-17.5%) vs 10.4% (95% CI: 9.2-11.6%), respectively]. We have detected six species of bacteria present in both types of areas, with different frequencies: dominance of B. afzelii (69.3%) in urban and B. garinii (48.1%) in natural areas. Although we observed higher tick densities in forests than in maintained parks, the prevalence of spirochaetes was significantly higher in the latter [9.8% (95% CI: 8.6-11.0%) vs 17.5% (95% CI: 14.4-20.5%)]. CONCLUSIONS Surprisingly, a similar risk of infection with Borreliella spp. and/or B. miyamotoi was discovered in highly- and low-transformed areas. We suggest that the awareness of presence of these disease agents in cities should be raised.
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Affiliation(s)
- Maciej Kowalec
- Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, 1 Miecznikowa Street, 02-096, Warsaw, Poland
| | - Tomasz Szewczyk
- W. Stefański Institute of Parasitology of the Polish Academy of Sciences, 51/55 Twarda Street, 00-818, Warsaw, Poland
| | - Renata Welc-Falęciak
- Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, 1 Miecznikowa Street, 02-096, Warsaw, Poland
| | - Edward Siński
- Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, 1 Miecznikowa Street, 02-096, Warsaw, Poland
| | - Grzegorz Karbowiak
- W. Stefański Institute of Parasitology of the Polish Academy of Sciences, 51/55 Twarda Street, 00-818, Warsaw, Poland
| | - Anna Bajer
- Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, 1 Miecznikowa Street, 02-096, Warsaw, Poland.
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Hofmeester TR, Sprong H, Jansen PA, Prins HHT, van Wieren SE. Deer presence rather than abundance determines the population density of the sheep tick, Ixodes ricinus, in Dutch forests. Parasit Vectors 2017; 10:433. [PMID: 28927432 PMCID: PMC5606071 DOI: 10.1186/s13071-017-2370-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 09/08/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Understanding which factors drive population densities of disease vectors is an important step in assessing disease risk. We tested the hypothesis that the density of ticks from the Ixodes ricinus complex, which are important vectors for tick-borne diseases, is determined by the density of deer, as adults of these ticks mainly feed on deer. METHODS We performed a cross-sectional study to investigate I. ricinus density across 20 forest plots in the Netherlands that ranged widely in deer availability to ticks, and performed a deer-exclosure experiment in four pairs of 1 ha forest plots in a separate site. RESULTS Ixodes ricinus from all stages were more abundant in plots with deer (n = 17) than in plots without deer (n = 3). Where deer were present, the density of ticks did not increase with the abundance of deer. Experimental exclosure of deer reduced nymph density by 66% and adult density by 32% within a timeframe of two years. CONCLUSIONS In this study, deer presence rather than abundance explained the density of I. ricinus. This is in contrast to previous studies and might be related to the relatively high host-species richness in Dutch forests. This means that reduction of the risk of acquiring a tick bite would require the complete elimination of deer in species rich forests. The fact that small exclosures (< 1 ha) substantially reduced I. ricinus densities suggests that fencing can be used to reduce tick-borne disease risk in areas with high recreational pressure.
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Affiliation(s)
- Tim R. Hofmeester
- Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708PB Wageningen, The Netherlands
| | - Hein Sprong
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Patrick A. Jansen
- Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708PB Wageningen, The Netherlands
- Center for Tropical Forest Science, Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama
| | - Herbert H. T. Prins
- Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708PB Wageningen, The Netherlands
| | - Sipke E. van Wieren
- Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708PB Wageningen, The Netherlands
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Hofhuis A, van de Kassteele J, Sprong H, van den Wijngaard CC, Harms MG, Fonville M, Docters van Leeuwen A, Simões M, van Pelt W. Predicting the risk of Lyme borreliosis after a tick bite, using a structural equation model. PLoS One 2017; 12:e0181807. [PMID: 28742149 PMCID: PMC5524385 DOI: 10.1371/journal.pone.0181807] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 07/09/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Understanding and quantification of the risk of Lyme borreliosis after a tick bite can aid development of prevention strategies against Lyme borreliosis. METHODS We used 3,525 single tick bite reports from three large prospective studies on the transmission risk of tick-borne pathogens to humans, with 50 reports of Lyme borreliosis during the follow-up period, among 1,973 reports with known outcome. A structural equation model was applied to estimate the risk of Lyme borreliosis after a tick bite, and quantify the influence of: developmental stage of the tick, detection of Borrelia burgdorferi s.l. DNA in the tick by PCR, tick engorgement, patient-estimated duration of tick attachment, and patient age. RESULTS The overall risk of developing Lyme borreliosis after a tick bite was 2.6% (95%CI 1.4-5.1). The risk increased with: - Tick engorgement: 1.4% (95%CI 0.7%-2.3%) for low engorgement to 5.5% (95%CI 2.8%-9.2%) for substantially engorged ticks;- Rising patient-estimated tick attachment duration: 2.0% (95%CI 1.3%-2.8%) after <12 hours, to 5.2% (95%CI 3.0%-8.9%) after ≥4 days;- Detection of Borrelia burgdorferi s.l. DNA in ticks: 6.7% (95%CI 3.6%-13.5%), versus 1.4% (95%CI 0.7%-2.9%) when ticks tested negative.The highest observed risk of Lyme borreliosis was 14.4% (95%CI 6.8%-24.6%) after one tick bite of a substantially engorged tick that tested positive for Borrelia burgdorferi s.l. DNA, which corresponds to one new case of Lyme borreliosis per 7 (95%CI 4-15) of such tick bites. CONCLUSIONS An individual's risk of Lyme borreliosis after a tick bite can be predicted with tick engorgement, patient-estimated duration of tick attachment, and detection of Borrelia burgdorferi s.l. DNA in the tick.
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Affiliation(s)
- Agnetha Hofhuis
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Jan van de Kassteele
- Department of Statistics, Informatics and Mathematical Modeling, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Hein Sprong
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Cees C van den Wijngaard
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Margriet G Harms
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Manoj Fonville
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Arieke Docters van Leeuwen
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Mariana Simões
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Wilfrid van Pelt
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
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Hofmeester TR, Rowcliffe JM, Jansen PA. Quantifying the Availability of Vertebrate Hosts to Ticks: A Camera-Trapping Approach. Front Vet Sci 2017; 4:115. [PMID: 28770219 PMCID: PMC5515830 DOI: 10.3389/fvets.2017.00115] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 07/03/2017] [Indexed: 11/13/2022] Open
Abstract
The availability of vertebrate hosts is a major determinant of the occurrence of ticks and tick-borne zoonoses in natural and anthropogenic ecosystems and thus drives disease risk for wildlife, livestock, and humans. However, it remains challenging to quantify the availability of vertebrate hosts in field settings, particularly for medium-sized to large-bodied mammals. Here, we present a method that uses camera traps to quantify the availability of warm-bodied vertebrates to ticks. The approach is to deploy camera traps at questing height at a representative sample of random points across the study area, measure the average photographic capture rate for vertebrate species, and then correct these rates for the effective detection distance. The resulting "passage rate" is a standardized measure of the frequency at which vertebrates approach questing ticks, which we show is proportional to contact rate. A field test across twenty 1-ha forest plots in the Netherlands indicated that this method effectively captures differences in wildlife assemblage composition between sites. Also, the relative abundances of three life stages of the sheep tick Ixodes ricinus from drag sampling were correlated with passage rates of deer, which agrees with the known association with this group of host species, suggesting that passage rate effectively reflects the availability of medium- to large-sized hosts to ticks. This method will facilitate quantitative studies of the relationship between densities of questing ticks and the availability of different vertebrate species-wild as well as domesticated species-in natural and anthropogenic settings.
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Affiliation(s)
- Tim R. Hofmeester
- Department of Environmental Sciences, Wageningen University, Wageningen, Netherlands
| | | | - Patrick A. Jansen
- Department of Environmental Sciences, Wageningen University, Wageningen, Netherlands
- Center for Tropical Forest Science, Smithsonian Tropical Research Institute, Balboa, Ancon, Panama
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Millins C, Gilbert L, Johnson P, James M, Kilbride E, Birtles R, Biek R. Heterogeneity in the abundance and distribution of Ixodes ricinus and Borrelia burgdorferi (sensu lato) in Scotland: implications for risk prediction. Parasit Vectors 2016; 9:595. [PMID: 27876087 PMCID: PMC5120507 DOI: 10.1186/s13071-016-1875-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 11/04/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cases of Lyme borreliosis, a vector-borne zoonosis caused by bacteria in the Borrelia burgdorferi (sensu lato) species group, have increased in recent years in Europe. Knowledge of environmental factors associated with abundance of the tick vector Ixodes ricinus and the pathogen B. burgdorferi (s.l.) is of interest to understand responses to environmental changes, predict variation in risk and to inform management interventions. METHODS Nineteen woodland sites across Scotland were surveyed in 2012 for B. burgdorferi (s.l.) infection in questing I. ricinus nymphs (n = 200 per site), deer abundance and vegetation. Climatic factors were extracted for each site. Six additional sites were surveyed for questing nymphs in both 2012 and 2013 (n = 200 per site and year) to test for variation in B. burgdorferi (s.l.) prevalence between years. RESULTS The mean prevalence of B. burgdorferi (s.l.) across 19 sites was 1.7% (95% CI: 1.4-2.2%; range 0-6%), all four genospecies known to be present in the UK were detected: B. garinii, B. afzelii, B. burgdorferi (sensu stricto) and B. valaisiana. A higher prevalence of B. burgdorferi (s.l.), higher densities of nymphs and higher densities of infected nymphs were found at sites with warmer climates, estimated with growing degree-days. No association between infection prevalence in nymphs and woodland type (semi-natural mixed vs coniferous) or deer density was found. At six sites sampled in 2012 and 2013, there was a significant increase in B. afzelli prevalence at two sites and a decrease in B. garinii prevalence at one site. CONCLUSIONS This study highlights challenges for the prediction of risk of Lyme borreliosis, reflecting the sensitivity of both pathogen and vector ecology to habitat, host and climatic factors. Significant changes in the prevalence of individual genospecies at sites monitored across time are likely to be due to variability in the host community composition between years. Our results indicate the importance of monitoring dynamic variables such as reservoir host populations as well as climate and habitat factors over multiple years, to identify environmental factors associated with Lyme borreliosis risk.
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Affiliation(s)
- Caroline Millins
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland. .,The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland.
| | - Lucy Gilbert
- James Hutton Institute, Craigiebuckler, Aberdeen, Scotland
| | - Paul Johnson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland.,The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland
| | - Marianne James
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK.,Division of Applied Medicine, University of Aberdeen, Aberdeen, UK.,Present Address: Food Standards Scotland, Aberdeen, Scotland
| | - Elizabeth Kilbride
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland
| | - Richard Birtles
- School of Environment and Life Sciences, University of Salford, Salford, UK
| | - Roman Biek
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland.,The Boyd Orr Centre for Population and Ecosystem Health, University of Glasgow, Glasgow, Scotland
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