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Maestas LP, Adams SL, Britten HB. First Evidence of an Established Population of Ixodes scapularis (Acari: Ixodidae) in South Dakota. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:965-966. [PMID: 27106935 DOI: 10.1093/jme/tjw038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
Ixodes scapularis Say (Acari: Ixodidae) is the most important vector of human disease in the United States. Recent efforts by public health officials to determine its presence on a county-by-county basis have been undertaken to assist in Lyme disease risk assessment. Recent modeling efforts show that South Dakota can potentially support populations of I. scapularis based on favorable climatic conditions and presence of suitable hosts to support tick populations within the state. We provide the first documentation of an established population of I. scapularis in Clay County, SD, providing only the third record of the presence of this tick species within the state.
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Affiliation(s)
- Lauren P Maestas
- Department of Biology, University of South Dakota, 414 East Clark St., Vermillion, SD 57069 (; ; ),
| | - Seryna L Adams
- Department of Biology, University of South Dakota, 414 East Clark St., Vermillion, SD 57069 (; ; )
| | - Hugh B Britten
- Department of Biology, University of South Dakota, 414 East Clark St., Vermillion, SD 57069 (; ; )
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152
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Walter KS, Pepin KM, Webb CT, Gaff HD, Krause PJ, Pitzer VE, Diuk-Wasser MA. Invasion of two tick-borne diseases across New England: harnessing human surveillance data to capture underlying ecological invasion processes. Proc Biol Sci 2016; 283:20160834. [PMID: 27252022 PMCID: PMC4920326 DOI: 10.1098/rspb.2016.0834] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 05/09/2016] [Indexed: 11/12/2022] Open
Abstract
Modelling the spatial spread of vector-borne zoonotic pathogens maintained in enzootic transmission cycles remains a major challenge. The best available spatio-temporal data on pathogen spread often take the form of human disease surveillance data. By applying a classic ecological approach-occupancy modelling-to an epidemiological question of disease spread, we used surveillance data to examine the latent ecological invasion of tick-borne pathogens. Over the last half-century, previously undescribed tick-borne pathogens including the agents of Lyme disease and human babesiosis have rapidly spread across the northeast United States. Despite their epidemiological importance, the mechanisms of tick-borne pathogen invasion and drivers underlying the distinct invasion trajectories of the co-vectored pathogens remain unresolved. Our approach allowed us to estimate the unobserved ecological processes underlying pathogen spread while accounting for imperfect detection of human cases. Our model predicts that tick-borne diseases spread in a diffusion-like manner with occasional long-distance dispersal and that babesiosis spread exhibits strong dependence on Lyme disease.
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Affiliation(s)
- Katharine S Walter
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT 06520, USA
| | - Kim M Pepin
- United States Department of Agriculture Animal and Plant Health Inspection Service, National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO 80521, USA Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Colleen T Webb
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Holly D Gaff
- Department of Biological Sciences, Old Dominion University, 302a Mills Godwin Building, Norfolk, VA 23529, USA
| | - Peter J Krause
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT 06520, USA
| | - Virginia E Pitzer
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT 06520, USA Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maria A Diuk-Wasser
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT 06520, USA Department of Ecology, Evolution, and Environmental Biology, Columbia University, 1200 Amsterdam Avenue, New York, NY 10027, USA
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153
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Ogden NH, Lindsay LR. Effects of Climate and Climate Change on Vectors and Vector-Borne Diseases: Ticks Are Different. Trends Parasitol 2016; 32:646-656. [PMID: 27260548 DOI: 10.1016/j.pt.2016.04.015] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 04/19/2016] [Accepted: 04/21/2016] [Indexed: 01/05/2023]
Abstract
There has been considerable debate as to whether global risk from vector-borne diseases will be impacted by climate change. This has focussed on important mosquito-borne diseases that are transmitted by the vectors from infected to uninfected humans. However, this debate has mostly ignored the biological diversity of vectors and vector-borne diseases. Here, we review how climate and climate change may impact those most divergent of arthropod disease vector groups: multivoltine insects and hard-bodied (ixodid) ticks. We contrast features of the life cycles and behaviour of these arthropods, and how weather, climate, and climate change may have very different impacts on the spatiotemporal occurrence and abundance of vectors, and the pathogens they transmit.
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Affiliation(s)
- Nick H Ogden
- National Microbiology Laboratory, Public Health Agency of Canada, 3200 Sicotte, Saint-Hyacinthe, Québec, J2S 7C6, Canada; Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada; National Microbiology Laboratory, Public Health Agency of Canada, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba, R3E 3R2, Canada.
| | - L Robbin Lindsay
- National Microbiology Laboratory, Public Health Agency of Canada, National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba, R3E 3R2, Canada
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154
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Miller MJ, Esser HJ, Loaiza JR, Herre EA, Aguilar C, Quintero D, Alvarez E, Bermingham E. Molecular Ecological Insights into Neotropical Bird-Tick Interactions. PLoS One 2016; 11:e0155989. [PMID: 27203693 PMCID: PMC4874597 DOI: 10.1371/journal.pone.0155989] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 05/06/2016] [Indexed: 11/19/2022] Open
Abstract
In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna). Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology and the dynamics of emerging tropical tick-borne pathogens should explicitly consider wild bird as hosts.
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Affiliation(s)
- Matthew J. Miller
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Department of Biology, Villanova University, Villanova, Pennsylvania, United States of America
- * E-mail:
| | - Helen J. Esser
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Department of Environmental Sciences, Wageningen University, Wageningen, the Netherlands
| | - Jose R. Loaiza
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Centro de Biodiversidad y Descubrimiento de Drogas, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), Panama City, Republic of Panama
- Centralamerican Master’s Program in Entomology, University of Panama, Panama City, Republic of Panama
| | - Edward Allen Herre
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Celestino Aguilar
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Centro de Biodiversidad y Descubrimiento de Drogas, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), Panama City, Republic of Panama
| | - Diomedes Quintero
- G. B. Fairchild Invertebrate Museum, University of Panama, Panama City, Republic of Panama
| | - Eric Alvarez
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Centralamerican Master’s Program in Entomology, University of Panama, Panama City, Republic of Panama
| | - Eldredge Bermingham
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Patricia and Phillip Frost Museum of Science, Miami, Florida, United States of America
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155
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Krakowetz CN, Dibernardo A, Lindsay LR, Chilton NB. Two Anaplasma phagocytophilum strains in Ixodes scapularis ticks, Canada. Emerg Infect Dis 2016; 20:2064-7. [PMID: 25417645 PMCID: PMC4257797 DOI: 10.3201/eid2012.140172] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We developed PCR-based assays to distinguish a human pathogenic strain of Anaplasma phagocytophilum, Ap-ha, from Ap-variant 1, a strain not associated with human infection. The assays were validated on A. phagocytophilum-infected black-legged ticks (Ixodes scapularis) collected in Canada. The relative prevalence of these 2 strains in I. scapularis ticks differed among geographic regions.
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156
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Nelder MP, Russell CB, Sheehan NJ, Sander B, Moore S, Li Y, Johnson S, Patel SN, Sider D. Human pathogens associated with the blacklegged tick Ixodes scapularis: a systematic review. Parasit Vectors 2016; 9:265. [PMID: 27151067 PMCID: PMC4857413 DOI: 10.1186/s13071-016-1529-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/21/2016] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The blacklegged tick Ixodes scapularis transmits Borrelia burgdorferi (sensu stricto) in eastern North America; however, the agent of Lyme disease is not the sole pathogen harbored by the blacklegged tick. The blacklegged tick is expanding its range into areas of southern Canada such as Ontario, an area where exposure to blacklegged tick bites and tick-borne pathogens is increasing. We performed a systematic review to evaluate the public health risks posed by expanding blacklegged tick populations and their associated pathogens. METHODS We followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for conducting our systematic review. We searched Ovid MEDLINE, Embase, BIOSIS, Scopus and Environment Complete databases for studies published from 2000 through 2015, using subject headings and keywords that included "Ixodes scapularis", "Rickettsia", "Borrelia", "Anaplasma", "Babesia" and "pathogen." Two reviewers screened titles and abstracts against eligibility criteria (i.e. studies that included field-collected blacklegged ticks and studies that did not focus solely on B. burgdorferi) and performed quality assessments on eligible studies. RESULTS Seventy-eight studies were included in the final review, 72 were from the US and eight were from Canada (two studies included blacklegged ticks from both countries). Sixty-four (82%) studies met ≥ 75% of the quality assessment criteria. Blacklegged ticks harbored 91 distinct taxa, 16 of these are tick-transmitted human pathogens, including species of Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia, Rickettsia, Theileria and Flavivirus. Organism richness was highest in the Northeast (Connecticut, New York) and Upper Midwest US (Wisconsin); however, organism richness was dependent on sampling effort. The primary tick-borne pathogens of public health concern in Ontario, due to the geographic proximity or historical detection in Ontario, are Anaplasma phagocytophilum, Babesia microti, B. burgdorferi, Borrelia miyamotoi, deer tick virus and Ehrlichia muris-like sp. Aside from B. burgdorferi and to a much lesser concern A. phagocytophilum, these pathogens are not immediate concerns to public health in Ontario; rather they represent future threats as the distribution of vectors and pathogens continue to proliferate. CONCLUSIONS Our review is the first systematic assessment of the literature on the human pathogens associated with the blacklegged tick. As Lyme disease awareness continues to increase, it is an opportune time to document the full spectrum of human pathogens transmittable by blacklegged ticks.
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Affiliation(s)
- Mark P Nelder
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada.
| | - Curtis B Russell
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Nina Jain Sheehan
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Beate Sander
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada
- Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
| | - Stephen Moore
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Ye Li
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, ON, Canada
| | - Steven Johnson
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, ON, Canada
| | - Samir N Patel
- Public Health Ontario Laboratories, Public Health Ontario, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Doug Sider
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
- Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada
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157
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Yunik MEM, Galloway TD, Lindsay LR. Assessment of prevalence and distribution of spotted fever group rickettsiae in Manitoba, Canada, in the American dog tick, Dermacentor variabilis (Acari: Ixodidae). Vector Borne Zoonotic Dis 2016; 15:103-8. [PMID: 25700040 DOI: 10.1089/vbz.2014.1692] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Little is known about the distribution and prevalence of the spotted fever group rickettsiae in Canada. We conducted active surveillance for tick-associated rickettsiae in 10 localities in Manitoba. A total of 1044 adult American dog ticks, Dermacentor variabilis (Acari: Ixodidae), were collected and screened for spotted fever group rickettsiae. Rickettsia montanensis was the only species of rickettsia detected. The mean prevalence of infection was 9.8% (range, 0.00-21.74% among localities). The proportion of infected male and female ticks was not significantly different; however, tick populations near the northern limit of D. variabilis distribution in Manitoba had a lower prevalence of infection compared to tick populations from more southern localities in the province.
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Affiliation(s)
- Matthew E M Yunik
- 1 Department of Entomology, University of Manitoba , Winnipeg, Manitoba, Canada
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158
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McCoy KD, Dietrich M, Jaeger A, Wilkinson DA, Bastien M, Lagadec E, Boulinier T, Pascalis H, Tortosa P, Le Corre M, Dellagi K, Lebarbenchon C. The role of seabirds of the Iles Eparses as reservoirs and disseminators of parasites and pathogens. ACTA OECOLOGICA (MONTROUGE, FRANCE) 2016; 72:98-109. [PMID: 32288503 PMCID: PMC7128210 DOI: 10.1016/j.actao.2015.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 12/30/2015] [Accepted: 12/30/2015] [Indexed: 11/30/2022]
Abstract
The role of birds as reservoirs and disseminators of parasites and pathogens has received much attention over the past several years due to their high vagility. Seabirds are particularly interesting hosts in this respect. In addition to incredible long-distance movements during migration, foraging and prospecting, these birds are long-lived, site faithful and breed in dense aggregations in specific colony locations. These different characteristics can favor both the local maintenance and large-scale dissemination of parasites and pathogens. The Iles Eparses provide breeding and feeding grounds for more than 3 million breeding pairs of seabirds including at least 13 species. Breeding colonies on these islands are relatively undisturbed by human activities and represent natural metapopulations in which seabird population dynamics, movement and dispersal can be studied in relation to that of circulating parasites and pathogens. In this review, we summarize previous knowledge and recently-acquired data on the parasites and pathogens found in association with seabirds of the Iles Eparses. These studies have revealed the presence of a rich diversity of infectious agents (viruses, bacteria and parasites) carried by the birds and/or their local ectoparasites (ticks and louse flies). Many of these agents are widespread and found in other ecosystems confirming a role for seabirds in their large scale dissemination and maintenance. The heterogeneous distribution of parasites and infectious agents among islands and seabird species suggests that relatively independent metacommunities of interacting species may exist within the western Indian Ocean. In this context, we discuss how the patterns and determinants of seabird movements may alter parasite and pathogen circulation. We conclude by outlining key aspects for future research given the baseline data now available and current concerns in eco-epidemiology and biodiversity conservation.
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Affiliation(s)
- Karen D. McCoy
- MIVEGEC (Maladies Infectieuses et Vecteurs: Evolution, Génétique, Ecologie, Contrôle) UMR 5290 CNRS-IRD-Université de Montpellier, Centre IRD, 34393 Montpellier, France
| | - Muriel Dietrich
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
| | - Audrey Jaeger
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR ENTROPIE, Université de la Réunion-IRD-CNRS, CS92003, 97744 Saint Denis, Reunion Island, France
| | - David A. Wilkinson
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Matthieu Bastien
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Erwan Lagadec
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Thierry Boulinier
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-Université de Montpellier UMR 5175, 34293 Montpellier, France
| | - Hervé Pascalis
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Pablo Tortosa
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Matthieu Le Corre
- UMR ENTROPIE, Université de la Réunion-IRD-CNRS, CS92003, 97744 Saint Denis, Reunion Island, France
| | - Koussay Dellagi
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
| | - Camille Lebarbenchon
- CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien), 97490 Sainte Clotilde, Reunion Island, France
- UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical), Université de La Réunion, INSERM 1187, CNRS 9192, IRD 249, 97490 Sainte Clotilde, Reunion Island, France
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159
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Berthová L, Slobodník V, Slobodník R, Olekšák M, Sekeyová Z, Svitálková Z, Kazimírová M, Špitalská E. The natural infection of birds and ticks feeding on birds with Rickettsia spp. and Coxiella burnetii in Slovakia. EXPERIMENTAL & APPLIED ACAROLOGY 2016; 68:299-314. [PMID: 26477038 DOI: 10.1007/s10493-015-9975-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 10/08/2015] [Indexed: 05/26/2023]
Abstract
Ixodid ticks (Acari: Ixodidae) are known as primary vectors of many pathogens causing diseases in humans and animals. Ixodes ricinus is a common ectoparasite in Europe and birds are often hosts of subadult stages of the tick. From 2012 to 2013, 347 birds belonging to 43 species were caught and examined for ticks in three sites of Slovakia. Ticks and blood samples from birds were analysed individually for the presence of Rickettsia spp. and Coxiella burnetii by PCR-based methods. Only I. ricinus was found to infest birds. In total 594 specimens of bird-attached ticks were collected (451 larvae, 142 nymphs, 1 female). Altogether 37.2% (16/43) of bird species were infested by ticks and some birds carried more than one tick. The great tit, Parus major (83.8%, 31/37) was the most infested species. In total, 6.6 and 2.7% of bird-attached ticks were infected with Rickettsia spp. and C. burnetii, respectively. Rickettsia helvetica predominated (5.9%), whereas R. monacensis (0.5%) was only sporadically detected. Coxiella burnetii was detected in 0.9%, Rickettsia spp. in 8.9% and R. helvetica in 4.2% of bird blood samples. The great tit was the bird species most infested with I. ricinus, carried R. helvetica and C. burnetti positive tick larvae and nymphs and was found to be rickettsaemic in its blood. Further studies are necessary to define the role of birds in the circulation of rickettsiae and C. burnetii in natural foci.
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160
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Mechai S, Margos G, Feil EJ, Barairo N, Lindsay LR, Michel P, Ogden NH. Evidence for Host-Genotype Associations of Borrelia burgdorferi Sensu Stricto. PLoS One 2016; 11:e0149345. [PMID: 26901761 PMCID: PMC4763156 DOI: 10.1371/journal.pone.0149345] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/29/2016] [Indexed: 11/18/2022] Open
Abstract
Different genotypes of the agent of Lyme disease in North America, Borrelia burgdorferi sensu stricto, show varying degrees of pathogenicity in humans. This variation in pathogenicity correlates with phylogeny and we have hypothesized that the different phylogenetic lineages in North America reflect adaptation to different host species. In this study, evidence for host species associations of B. burgdorferi genotypes was investigated using 41 B. burgdorferi-positive samples from five mammal species and 50 samples from host-seeking ticks collected during the course of field studies in four regions of Canada: Manitoba, northwestern Ontario, Quebec, and the Maritimes. The B. burgdorferi genotypes in the samples were characterized using three established molecular markers (multi-locus sequence typing [MLST], 16S-23S rrs-rrlA intergenic spacer, and outer surface protein C sequence [ospC] major groups). Correspondence analysis and generalized linear mixed effect models revealed significant associations between B. burgdorferi genotypes and host species (in particular chipmunks, and white-footed mice and deer mice), supporting the hypotheses that host adaptation contributes to the phylogenetic structure and possibly the observed variation in pathogenicity in humans.
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Affiliation(s)
- Samir Mechai
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
| | - Gabriele Margos
- National Reference Centre for Borrelia, Oberschleissheim, Germany
- Bavarian Health and Food Safety Authority, Oberschleissheim, Germany
| | - Edward J. Feil
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Nicole Barairo
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - L. Robbin Lindsay
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Pascal Michel
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
- National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, Québec, Canada
| | - Nicholas H. Ogden
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
- National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, Québec, Canada
- * E-mail:
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161
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Six RH, Young DR, Myers MR, Mahabir SP. Comparative speed of kill of sarolaner (Simparica) and afoxolaner (NexGard against induced infestations of Ixodes scapularis on dogs. Parasit Vectors 2016; 9:79. [PMID: 26876891 PMCID: PMC4753652 DOI: 10.1186/s13071-016-1307-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 01/14/2016] [Indexed: 11/16/2022] Open
Abstract
Background The black-legged (or deer) tick, Ixodes scapularis, commonly infests dogs and cats in North America and is the main vector for the pathogen that causes Lyme disease in dogs and humans. The speed of kill of a parasiticide is critical to minimize the direct and deleterious effects of tick infestation and especially to reduce the risk of tick-borne pathogen transmission. In this study, speed of kill of a novel orally administered isoxazoline parasiticide, sarolaner chewable tablets (Simparica™), against I. scapularis on dogs was evaluated and compared with afoxolaner (NexGard®) for five weeks after a single oral dose. Methods Twenty four dogs were randomly allocated to treatment with either placebo, sarolaner (2 to 4 mg/kg), or afoxolaner (2.5 to 6.8 mg/kg) based on pretreatment tick counts. Dogs were examined and live ticks counted at 8, 12, and 24 h after treatment and subsequent re-infestations on Days 7, 14, 21, 28 and 35. Efficacy was determined at each time point relative to counts for placebo dogs. Results A single oral dose of sarolaner provided >99 % efficacy within 24 h of treatment and >95 % against subsequent weekly re-infestations of ticks consistently to Day 35. For the earlier time points, sarolaner significantly reduced tick counts versus placebo from Day 0 to Day 21 at 8 and 12 h, and on Day 35 at 12 h (P ≤ 0.0174), while afoxolaner was only significantly lower at 8 h on Days 0 and 14 (P ≤ 0.0309), and at 12 h on Day 0 only (P < 0.0001). Significantly more live ticks were recovered from afoxolaner-treated dogs than from sarolaner-treated dogs at 24 h after infestation from Day 14 to Day 35 (P ≤ 0.0278). At 24 h, efficacy (based on geometric mean counts) of afoxolaner declined to less than 80 % from Day 21 through the end of the study, while efficacy for sarolaner was >95 % for 35 days. There were no adverse reactions to treatments. Conclusions In this controlled laboratory evaluation, sarolaner had a faster speed of kill against I. scapularis than afoxolaner. This was noticeably more pronounced towards the end of the monthly treatment period. The rapid and consistent kill of ticks provided by sarolaner within 24 h after a single oral dose and re-infestation over 35 days suggests this treatment will provide highly effective and reliable control of ticks over the entire treatment interval, and should reduce the risk of tick-borne diseases, including Lyme disease whose agent is vectored by I. scapularis.
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Affiliation(s)
- Robert H Six
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St., Kalamazoo, MI, 49007, USA.
| | | | - Melanie R Myers
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St., Kalamazoo, MI, 49007, USA.
| | - Sean P Mahabir
- Zoetis, Veterinary Medicine Research and Development, 333 Portage St., Kalamazoo, MI, 49007, USA.
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Clow KM, Ogden NH, Lindsay LR, Michel P, Pearl DL, Jardine CM. Distribution of Ticks and the Risk of Lyme Disease and Other Tick-Borne Pathogens of Public Health Significance in Ontario, Canada. Vector Borne Zoonotic Dis 2016; 16:215-22. [PMID: 26870937 DOI: 10.1089/vbz.2015.1890] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Over the past two decades, the northward spread of Ixodes scapularis across Ontario, Canada, has accelerated and the risk of Lyme disease has increased. Active surveillance is a recognized and effective method for detecting reproducing populations of I. scapularis. In this study, we conducted field sampling consistent with an active surveillance approach from May to October 2014 at 104 sites in central, eastern, and southern Ontario to determine the current distribution of I. scapularis and other tick species, and enhance our understanding of the geographic risk associated with Borrelia burgdorferi and other tick-borne pathogens of public health significance in this region. I. scapularis was present at 20 of the 104 sites visited. Individuals of the tick species Dermacentor variabilis, Haemaphysalis leporispalustris, and Ixodes dentatus were also collected. I. scapularis was positive by PCR for B. burgdorferi at five sites. These sites formed a significant spatial cluster in eastern Ontario. No ticks were PCR positive for Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia microti. This study provides an up-to-date picture of the distribution of I. scapularis and other tick species, and the risk of B. burgdorferi and other pathogens of public health significance in central, eastern, and southern Ontario. This information may allow for more effective surveillance efforts and public health interventions for Lyme disease and other tick-borne diseases in this region.
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Affiliation(s)
- Katie M Clow
- 1 Department of Pathobiology, Ontario Veterinary College, University of Guelph , Guelph, Canada
| | - Nicholas H Ogden
- 2 National Microbiology Laboratory, Public Health Agency of Canada, Saint Hyacinthe, Canada
| | - L Robbin Lindsay
- 3 National Microbiology Laboratory , Public Health Agency of Canada, Winnipeg, Canada
| | - Pascal Michel
- 4 Office of the Chief Science Officer, Public Health Agency of Canada, Ottawa, Canada
| | - David L Pearl
- 5 Department of Population Medicine, Ontario Veterinary College, University of Guelph , Guelph, Canada
| | - Claire M Jardine
- 1 Department of Pathobiology, Ontario Veterinary College, University of Guelph , Guelph, Canada
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Molecular detection of bacteria in the families Rickettsiaceae and Anaplasmataceae in northern crested caracaras (Caracara cheriway). Ticks Tick Borne Dis 2016; 7:470-4. [PMID: 26837860 DOI: 10.1016/j.ttbdis.2016.01.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 01/05/2016] [Accepted: 01/23/2016] [Indexed: 11/22/2022]
Abstract
Bacterial pathogens of the families Anaplasmataceae and Rickettsiaceae are often spread to humans or other animals from bites from infected arthropod hosts. Recently, an increasing number of studies have implicated migratory birds in the circulation of these pathogens through the spread of arthropod vectors. However, few studies have examined the potential for resident bird populations to serve as reservoirs for these zoonoses. In this study, we used nested PCRs of the GroESL and 17 kDa genes to screen for Anaplasmataceae and Rickettsiaceae, respectively, in a resident population of the northern crested caracara (Caracara cheriway) from Florida (n=55). Additionally, a small number (n=6) of captive individuals from Texas were included. We identified one individual (1.64%) positive for Rickettsia felis and one (1.64%) positive for Ehrlichia chaffeensis; both these individuals were from Florida. Presence of these pathogens demonstrates that these birds are potential hosts; however, the low prevalence of infections suggests that these populations likely do not function as an ecological reservoir.
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164
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Complex population structure of Borrelia burgdorferi in southeastern and south central Canada as revealed by phylogeographic analysis. Appl Environ Microbiol 2016; 81:1309-18. [PMID: 25501480 DOI: 10.1128/aem.03730-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lyme disease, caused by the bacterium Borrelia burgdorferi sensu stricto, is an emerging zoonotic disease in Canada and is vectored by the blacklegged tick, Ixodes scapularis. Here we used Bayesian analyses of sequence types (STs), determined by multilocus sequence typing (MLST), to investigate the phylogeography of B. burgdorferi populations in southern Canada and the United States by analyzing MLST data from 564 B. burgdorferi-positive samples collected during surveillance. A total of 107 Canadian samples from field sites were characterized as part of this study, and these data were combined with existing MLST data for samples from the United States and Canada. Only 17% of STs were common between both countries, while 49% occurred only in the United States, and 34% occurred only in Canada. However, STs in southeastern Ontario and southwestern Quebec were typically identical to those in the northeastern United States, suggesting a recent introduction into this region from the United States. In contrast, STs in other locations in Canada (the Maritimes; Long Point, Ontario; and southeastern Manitoba) were frequently unique to those locations but were putative descendants of STs previously found in the United States. The picture in Canada is consistent with relatively recent introductions from multiple refugial populations in the United States. These data thus point to a geographic pattern of populations of B. burgdorferi in North America that may be more complex than simply comprising northeastern, midwestern, and Californian groups. We speculate that this reflects the complex ecology and spatial distribution of key reservoir hosts.
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165
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Scott JD, Foley JE, Clark KL, Anderson JF, Durden LA, Manord JM, Smith ML. Established Population of Blacklegged Ticks with High Infection Prevalence for the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, on Corkscrew Island, Kenora District, Ontario. Int J Med Sci 2016; 13:881-891. [PMID: 27877080 PMCID: PMC5118759 DOI: 10.7150/ijms.16922] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/26/2016] [Indexed: 12/24/2022] Open
Abstract
We document an established population of blacklegged ticks, Ixodes scapularis, on Corkscrew Island, Kenora District, Ontario, Canada. Primers of the outer surface protein A (OspA) gene, the flagellin (fla) gene, and the flagellin B (flaB) gene were used in the PCR assays to detect Borrelia burgdorferi sensu lato (s.l.), the Lyme disease bacterium. In all, 60 (73%) of 82 adult I. scapularis, were infected with B. burgdorferi s.l. As well, 6 (43%) of 14 unfed I. scapularis nymphs were positive for B. burgdorferi s.l. An I. scapularis larva was also collected from a deer mouse, and several unfed larvae were gathered by flagging leaf litter. Based on DNA sequencing of randomly selected Borrelia amplicons from six nymphal and adult I. scapularis ticks, primers for the flagellin (fla) and flagellin B (flaB) genes reveal the presence of B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. We collected all 3 host-feeding life stages of I. scapularis in a single year, and report the northernmost established population of I. scapularis in Ontario. Corkscrew Island is hyperendemic for Lyme disease and has the highest prevalence of B. burgdorferi s.l. for any established population in Canada. Because of this very high infection prevalence, this population of I. scapularis has likely been established for decades. Of epidemiological significance, cottage owners, island visitors, outdoors enthusiasts, and medical professionals must be vigilant that B. burgdorferi s.l.-infected I. scapularis on Corkscrew Island pose a serious public health risk.
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Affiliation(s)
- John D Scott
- Lyme Ontario, Research Division, 365 St. David St. South, Fergus, Ontario, Canada N1M 2L7
| | - Janet E Foley
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California 95616, United States of America
| | - Kerry L Clark
- Epidemiology & Environmental Health, Department of Public Health, University of North Florida, 1 UNF Drive, Jacksonville, Florida 32224, United States of America
| | - John F Anderson
- Department of Entomology and Center for Vector Ecology and Zoonotic Diseases. The Connecticut Agricultural Experiment Station, P.O. Box 1106, New Haven, Connecticut 06504-1106, United States of America
| | - Lance A Durden
- Department of Biology, Georgia Southern University, 4324 Old Register Road, Statesboro, Georgia 30458, United States of America
| | - Jodi M Manord
- Epidemiology & Environmental Health, Department of Public Health, University of North Florida, 1 UNF Drive, Jacksonville, Florida 32224, United States of America
| | - Morgan L Smith
- Epidemiology & Environmental Health, Department of Public Health, University of North Florida, 1 UNF Drive, Jacksonville, Florida 32224, United States of America
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Scott JD, Foley JE. Detection of <i>Borrelia americana</i> in the Avian Coastal Tick, <i>Ixodes auritulus</i> (Acari: Ixodidae), Collected from a Bird Captured in Canada. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/ojas.2016.63027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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167
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Scott JD, Anderson JF, Durden LA, Smith ML, Manord JM, Clark KL. Prevalence of the Lyme Disease Spirochete, Borrelia burgdorferi, in Blacklegged Ticks, Ixodes scapularis at Hamilton-Wentworth, Ontario. Int J Med Sci 2016; 13:316-24. [PMID: 27226771 PMCID: PMC4879763 DOI: 10.7150/ijms.14552] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 03/21/2016] [Indexed: 01/24/2023] Open
Abstract
Lyme disease has emerged as a major health concern in Canada, where the etiological agent, Borrelia burgdorferi sensu lato (s.l.), a spirochetal bacterium, is typically spread by the bite of certain ticks. This study explores the presence of B. burgdorferi s.l. in blacklegged ticks, Ixodes scapularis, collected at Dundas, Ontario (a locality within the region of Hamilton-Wentworth). Using passive surveillance, veterinarians and pet groomers were asked to collect blacklegged ticks from dogs and cats with no history of travel. Additionally, I. scapularis specimens were submitted from local residents and collected by flagging. Overall, 12 (41%) of 29 blacklegged ticks were infected with B. burgdorferi s.l. Using polymerase chain reaction (PCR) and DNA sequencing, two borrelial amplicons were characterized as B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. Notably, three different vertebrate hosts each had two engorged I. scapularis females removed on the same day and, likewise, one cat had three repeat occurrences of this tick species. These multiple infestations suggest that a population of I. scapularis may be established in this area. The local public health unit has been underreporting the presence of B. burgdorferi s.l.-infected I. scapularis in the area encompassing Dundas. Our findings raise concerns about the need to erect tick warning signs in parkland areas. Veterinarians, medical professionals, public health officials, and the general public must be vigilant that Lyme disease-carrying blacklegged ticks pose a public health risk in the Dundas area and the surrounding Hamilton-Wentworth region.
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Affiliation(s)
- John D Scott
- 1. Research Division, Lyme Ontario, Fergus, Ontario, Canada N1M 2L7
| | - John F Anderson
- 2. Department of Entomology and Center for Vector Ecology and Zoonotic Diseases. The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA 06511
| | - Lance A Durden
- 3. Department of Biology, Georgia Southern University, Statesboro, Georgia, USA 30458
| | - Morgan L Smith
- 4. Environmental Epidemiology Research Laboratory, Department of Public Health, University of North Florida, Jacksonville, Florida, USA 32224
| | - Jodi M Manord
- 4. Environmental Epidemiology Research Laboratory, Department of Public Health, University of North Florida, Jacksonville, Florida, USA 32224
| | - Kerry L Clark
- 4. Environmental Epidemiology Research Laboratory, Department of Public Health, University of North Florida, Jacksonville, Florida, USA 32224
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168
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Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population. Bull Math Biol 2015; 78:138-68. [PMID: 26688012 DOI: 10.1007/s11538-015-0133-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 11/27/2015] [Indexed: 01/23/2023]
Abstract
Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control.
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169
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Yang J, Liu Z, Niu Q, Tian Z, Liu J, Guan G, Liu G, Luo J, Wang X, Yin H. Tick-borne zoonotic pathogens in birds in Guangxi, Southwest China. Parasit Vectors 2015; 8:637. [PMID: 26666827 PMCID: PMC4678635 DOI: 10.1186/s13071-015-1249-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/04/2015] [Indexed: 11/10/2022] Open
Abstract
Background Wildlife is an important natural reservoir of many tick-borne pathogens. These agents have an impact on the health of humans and other animals throughout the world. This study was conducted to determine whether and what species of tick-borne agents had infected wild birds collected from Guangxi, in southwest China. Findings Liver samples obtained from wild birds were tested for the presence of tick-borne pathogens by PCR assays and sequencing of the flagellin and 16S rRNA genes. Borrelia garinii was detected in Eurasian collared doves (2/57, 3.5 %) from among the 95 wild birds. Anaplasma phagocytophilum was detected in Eurasian collared doves (2/57, 3.5 %) and Eurasian eagle owls (2/13, 15.4 %). Ehrlichia chaffeensis and a potential novel Anaplasma sp. were identified in Common pheasant (1/12, 8.3 %). These results suggest the involvement of birds in the cycle of tick-borne diseases. To our knowledge, this is the first study to document infection of birds with B. garinii, A. phagocytophilum, E. chaffeensis and the novel Anaplasma sp. in China. Conclusions Tick-borne zoonotic bacteria B. garinii, A. phagocytophilum and E. chaffeensis, and a potential novel Anaplasma sp., were identified in wild birds in southwest China. The presence of these agents in birds increases the potential spread over long distances and the risk of transmission of infection from birds to new hosts, including humans.
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Affiliation(s)
- Jifei Yang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Zhijie Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Qingli Niu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Zhancheng Tian
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Junlong Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Guiquan Guan
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Guangyuan Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Jianxun Luo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China.
| | - Xiaolong Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China. .,Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang, 150040, P. R. China.
| | - Hong Yin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, P. R. China. .,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, P. R. China.
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170
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Ozdenerol E. GIS and Remote Sensing Use in the Exploration of Lyme Disease Epidemiology. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:15182-203. [PMID: 26633445 PMCID: PMC4690907 DOI: 10.3390/ijerph121214971] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 09/09/2015] [Accepted: 10/21/2015] [Indexed: 12/04/2022]
Abstract
Given the relatively recent recognition of Lyme disease (LD) by CDC in 1990 as a nationally notifiable infectious condition, the rise of reported human cases every year argues for a better understanding of its geographic scope. The aim of this inquiry was to explore research conducted on spatiotemporal patterns of Lyme disease in order to identify strategies for implementing vector and reservoir-targeted interventions. The focus of this review is on the use of GIS-based methods to study populations of the reservoir hosts, vectors and humans in addition to the spatiotemporal interactions between these populations. New GIS-based studies are monitoring occurrence at the macro-level, and helping pinpoint areas of occurrence at the micro-level, where spread within populations of reservoir hosts, clusters of infected ticks and tick to human transmission may be better understood.
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Affiliation(s)
- Esra Ozdenerol
- Department of Earth Sciences, University of Memphis, Memphis, TN 38152, USA.
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172
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Nuclear Markers Reveal Predominantly North to South Gene Flow in Ixodes scapularis, the Tick Vector of the Lyme Disease Spirochete. PLoS One 2015; 10:e0139630. [PMID: 26536360 PMCID: PMC4633295 DOI: 10.1371/journal.pone.0139630] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/14/2015] [Indexed: 12/04/2022] Open
Abstract
Ixodes scapularis, the tick vector of the Lyme disease spirochete, is distributed over most of the eastern United States, but >80% of all Lyme disease cases occur in the northeast. The role that genetic differences between northern and southern tick populations play in explaining this disparate distribution of Lyme disease cases is unclear. The present study was conducted with 1,155 SNP markers in eight nuclear genes; the 16S mitochondrial gene was examined for comparison with earlier studies. We examined 350 I. scapularis from 7 states covering a representative area of the species. A demographic analysis using Bayesian Extended Skyline Analysis suggested that I. scapularis populations in Mississippi and Georgia began expanding 500,000 years ago, those in Florida and North Carolina 200,000 years ago and those from Maryland and New Jersey only during the past 50,000 years with an accompanying bottleneck. Wisconsin populations only began expanding in the last 20,000 years. Analysis of current migration patterns suggests large amounts of gene flow in northern collections and equally high rates of gene flow among southern collections. In contrast there is restricted and unidirectional gene flow between northern and southern collections, mostly occurring from northern into southern populations. Northern populations are characterized by nymphs that quest above the leaf litter, are easy to collect by flagging, frequently feed on mammals such as rodents and shrews, commonly attach to people, and about 25% of which are infected with B. burgdorferi. If there is a genetic basis for these behaviors, then the patterns detected in this study are of concern because they suggest that northern I. scapularis populations with a greater ability to vector B. burgdorferi to humans are expanding south.
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173
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Avian migrants facilitate invasions of neotropical ticks and tick-borne pathogens into the United States. Appl Environ Microbiol 2015; 81:8366-78. [PMID: 26431964 DOI: 10.1128/aem.02656-15] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 09/21/2015] [Indexed: 11/20/2022] Open
Abstract
Migratory birds have the potential to transport exotic vectors and pathogens of human and animal health importance across vast distances. We systematically examined birds that recently migrated to the United States from the Neotropics for ticks. We screened both ticks and birds for tick-borne pathogens, including Rickettsia species and Borrelia burgdorferi. Over two spring seasons (2013 and 2014), 3.56% of birds (n = 3,844) representing 42.35% of the species examined (n = 85) were infested by ticks. Ground-foraging birds with reduced fuel stores were most commonly infested. Eight tick species were identified, including seven in the genus Amblyomma, of which only Amblyomma maculatum/Amblyomma triste is known to be established in the United States. Most ticks on birds (67%) were neotropical species with ranges in Central and South America. Additionally, a single Ixodes genus tick was detected. A total of 29% of the ticks (n = 137) and no avian blood samples (n = 100) were positive for infection with Rickettsia species, including Rickettsia parkeri, an emerging cause of spotted fever in humans in the southern United States, a species in the group of Rickettsia monacensis, and uncharacterized species and endosymbionts of unknown pathogenicity. No avian tick or blood samples tested positive for B. burgdorferi, the etiologic agent of Lyme disease. An extrapolation of our findings suggests that anywhere from 4 to 39 million exotic neotropical ticks are transported to the United States annually on migratory songbirds, with uncertain consequences for human and animal health if the current barriers to their establishment and spread are overcome.
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O'Brien SF, Delage G, Scalia V, Lindsay R, Bernier F, Dubuc S, Germain M, Pilot G, Yi QL, Fearon MA. Seroprevalence of Babesia microti infection in Canadian blood donors. Transfusion 2015; 56:237-43. [PMID: 26426217 DOI: 10.1111/trf.13339] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND Human babesiosis, caused by the intraerythrocytic protozoan parasite Babesia microti, is primarily transmitted by tick bites and is also transmitted by transfusion. Infections have been identified in U.S. blood donors close to Canadian borders. We aimed to assess the risk of transfusion-transmitted babesiosis in Canada by examining infections in ticks and seroprevalence in blood donors. STUDY DESIGN AND METHODS Passive surveillance (receipt of ticks submitted by the public) was used to identify regions for tick drag sampling (active surveillance, 2009-2014). All ticks were tested for B. microti using an indirect immunofluorescent antibody assay (Imugen, Inc.). Between July and December 2013, blood donations from selected sites (southern Manitoba, Ontario, Québec, New Brunswick, and Nova Scotia) near endemic U.S. regions were tested for antibody to B. microti. Donors completed a questionnaire about risk travel and possible tick exposure. RESULTS Of approximately 12,000 ticks submitted, 14 were B. microti positive (10 in Manitoba, one in Ontario, one in Québec, two in New Brunswick). From active tick surveillance, six of 361 ticks in Manitoba were positive (1.7%), three of 641 (0.5%) in Québec, and none elsewhere. There were 26,260 donors at the selected sites of whom 13,993 (53%) were tested. None were positive for antibody to B. microti. In 2013, 47% of donors visited forested areas in Canada, and 41% traveled to the United States. CONCLUSION The data do not suggest that laboratory-based testing is warranted at this time. However, there are indicators that B. microti may be advancing into Canada and ongoing monitoring of tick populations and donor seroprevalence is indicated.
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Affiliation(s)
| | | | - Vito Scalia
- Canadian Blood Services, Ottawa, Ontario, Canada
| | - Robbin Lindsay
- Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | | | | | | | - Gerry Pilot
- Canadian Blood Services, Ottawa, Ontario, Canada
| | - Qi-Long Yi
- Canadian Blood Services, Ottawa, Ontario, Canada
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175
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Cross-Immunity and Community Structure of a Multiple-Strain Pathogen in the Tick Vector. Appl Environ Microbiol 2015; 81:7740-52. [PMID: 26319876 DOI: 10.1128/aem.02296-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 08/25/2015] [Indexed: 12/11/2022] Open
Abstract
Many vector-borne pathogens consist of multiple strains that circulate in both the vertebrate host and the arthropod vector. Characterization of the community of pathogen strains in the arthropod vector is therefore important for understanding the epidemiology of mixed vector-borne infections. Borrelia afzelii and B. garinii are two species of tick-borne bacteria that cause Lyme disease in humans. These two sympatric pathogens use the same tick, Ixodes ricinus, but are adapted to different classes of vertebrate hosts. Both Borrelia species consist of multiple strains that are classified using the highly polymorphic ospC gene. Vertebrate cross-immunity against the OspC antigen is predicted to structure the community of multiple-strain Borrelia pathogens. Borrelia isolates were cultured from field-collected I. ricinus ticks over a period spanning 11 years. The Borrelia species of each isolate was identified using a reverse line blot (RLB) assay. Deep sequencing was used to characterize the ospC communities of 190 B. afzelii isolates and 193 B. garinii isolates. Infections with multiple ospC strains were common in ticks, but vertebrate cross-immunity did not influence the strain structure in the tick vector. The pattern of genetic variation at the ospC locus suggested that vertebrate cross-immunity exerts strong selection against intermediately divergent ospC alleles. Deep sequencing found that more than 50% of our isolates contained exotic ospC alleles derived from other Borrelia species. Two alternative explanations for these exotic ospC alleles are cryptic coinfections that were not detected by the RLB assay or horizontal transfer of the ospC gene between Borrelia species.
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176
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Abstract
Current approaches for prevention of tick bites, Lyme disease, and other tick-borne diseases are described. Particular attention is paid to 4 risk-reduction strategies: (i) avoiding risk areas; (ii) personal protective measures that reduce the risk of tick bites or transmission of the agent of Lyme disease, Borrelia burgdorferi; (iii) reducing the number of infected ticks in the environment; and (iv) use of prophylactic antibiotic treatments following a bite to prevent clinical Lyme disease.
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Affiliation(s)
- Nick H Ogden
- National Microbiology Laboratory, Public Health Agency of Canada, 3200 Sicotte, Saint-Hyacinthe, Quebec J2S 7C6, Canada.
| | - L Robbin Lindsay
- National Microbiology Laboratory, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba R3E 3R2, Canada
| | - Steven W Schofield
- Communicable Disease Control Program, Force Health Protection, Department of National Defence, 1745 Alta Vista Drive, Ottawa, Ontario K1A 0K6, Canada
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177
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Nadolny R, Gaff H, Carlsson J, Gauthier D. Comparative population genetics of two invading ticks: Evidence of the ecological mechanisms underlying tick range expansions. INFECTION GENETICS AND EVOLUTION 2015; 35:153-62. [PMID: 26254575 DOI: 10.1016/j.meegid.2015.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/29/2015] [Accepted: 08/04/2015] [Indexed: 11/18/2022]
Abstract
Two species of ixodid tick, Ixodes affinis Neumann and Amblyomma maculatum Koch, are simultaneously expanding their ranges throughout the mid-Atlantic region of the US. Although we have some understanding of the ecology and life history of these species, the ecological mechanisms governing where and how new populations establish and persist are unclear. To assess population connectivity and ancestry, we sequenced a fragment of the 16S mitochondrial rRNA gene from a representative sample of individuals of both species from populations throughout the eastern US. We found that despite overlapping host preferences throughout ontogeny, each species exhibited very different genetic and geographic patterns of population establishment and connectivity. I. affinis was of two distinct mitochondrial clades, with a clear geographic break separating northern and southern populations. Both I. affinis populations showed evidence of recent expansion, although the southern population was more genetically diverse, indicating a longer history of establishment. A. maculatum exhibited diverse haplotypes that showed no significant relationship with geographic patterns and little apparent connectivity between sites. Heteroplasmy was also observed in the 16S mitochondrial rRNA gene in 3.5% of A. maculatum individuals. Genetic evidence suggests that these species rely on different key life stages to successfully disperse into novel environments, and that host vagility, habitat stability and habitat connectivity all play critical roles in the establishment of new tick populations.
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Affiliation(s)
- Robyn Nadolny
- Old Dominion University, Dept. of Biological Sciences, Norfolk, VA, USA.
| | - Holly Gaff
- Old Dominion University, Dept. of Biological Sciences, Norfolk, VA, USA; University of KwaZulu-Natal, School of Mathematics, Statistics and Computer Science, South Africa
| | - Jens Carlsson
- Area 52 Research Group, School of Biology & Environment Science and Earth Institute, University College Dublin, Belfield, Dublin, Ireland
| | - David Gauthier
- Old Dominion University, Dept. of Biological Sciences, Norfolk, VA, USA
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Khatchikian CE, Prusinski MA, Stone M, Backenson PB, Wang IN, Foley E, Seifert SN, Levy MZ, Brisson D. Recent and rapid population growth and range expansion of the Lyme disease tick vector, Ixodes scapularis, in North America. Evolution 2015; 69:1678-89. [PMID: 26149959 DOI: 10.1111/evo.12690] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 03/31/2015] [Indexed: 10/23/2022]
Abstract
Migration is a primary force of biological evolution that alters allele frequencies and introduces novel genetic variants into populations. Recent migration has been proposed as the cause of the emergence of many infectious diseases, including those carried by blacklegged ticks in North America. Populations of blacklegged ticks have established and flourished in areas of North America previously thought to be devoid of this species. The recent discovery of these populations of blacklegged ticks may have resulted from either in situ growth of long-established populations that were maintained at very low densities or by migration and colonization from established populations. These alternative evolutionary hypotheses were investigated using Bayesian phylogeographic approaches to infer the origin and migratory history of recently detected blacklegged tick populations in the Northeastern United States. The data and results indicate that newly detected tick populations are not the product of in situ population growth from a previously established population but from recent colonization resulting in a geographic range expansion. This expansion in the geographic range proceeded primarily through progressive and local migration events from southern populations to proximate northern locations although long-distance migration events were also detected.
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Affiliation(s)
| | | | - Melissa Stone
- State University of New York, Albany, New York, 12222
| | - Peter Bryon Backenson
- New York Department of Health, Albany, New York, 12237.,State University of New York, Albany, New York, 12222
| | - Ing-Nang Wang
- State University of New York, Albany, New York, 12222
| | - Erica Foley
- University of Pennsylvania, Philadelphia, Pennsylvania, 19104
| | | | - Michael Z Levy
- University of Pennsylvania, Philadelphia, Pennsylvania, 19104
| | - Dustin Brisson
- University of Pennsylvania, Philadelphia, Pennsylvania, 19104.
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179
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Bouchard C, Leonard E, Koffi JK, Pelcat Y, Peregrine A, Chilton N, Rochon K, Lysyk T, Lindsay LR, Ogden NH. The increasing risk of Lyme disease in Canada. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 2015; 56:693-699. [PMID: 26130829 PMCID: PMC4466818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
There is an increasing risk of Lyme disease in Canada due to range expansion of the tick vector, Ixodes scapularis. The objectives of this article are to i) raise public awareness with the help of veterinarians on the emerging and expanding risk of Lyme disease across Canada, ii) review the key clinical features of Lyme disease in dogs, and iii) provide recommendations for veterinarians on the management of Lyme disease in dogs.
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180
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Gabriele-Rivet V, Arsenault J, Badcock J, Cheng A, Edsall J, Goltz J, Kennedy J, Lindsay LR, Pelcat Y, Ogden NH. Different Ecological Niches for Ticks of Public Health Significance in Canada. PLoS One 2015; 10:e0131282. [PMID: 26131550 PMCID: PMC4489490 DOI: 10.1371/journal.pone.0131282] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/01/2015] [Indexed: 01/07/2023] Open
Abstract
Tick-borne diseases are a growing public health concern as their incidence and range have increased in recent decades. Lyme disease is an emerging infectious disease in Canada due to northward expansion of the geographic range of Ixodes scapularis, the principal tick vector for the Lyme disease agent Borrelia burgdorferi, into central and eastern Canada. In this study the geographical distributions of Ixodid ticks, including I. scapularis, and environmental factors associated with their occurrence were investigated in New Brunswick, Canada, where few I. scapularis populations have been found to date. Density of host-seeking ticks was evaluated by drag sampling of woodland habitats in a total of 159 sites. Ixodes scapularis ticks (n = 5) were found on four sites, Ixodes muris (n = 1) on one site and Haemaphysalis leporispalustris (n = 243) on 41 sites. One of four adult I. scapularis ticks collected was PCR-positive for B. burgdorferi. No environmental variables were significantly associated with the presence of I. scapularis although comparisons with surveillance data in neighbouring provinces (Québec and Nova Scotia) suggested that temperature conditions may be too cold for I. scapularis (< 2800 annual degree days above 0°C [DD > 0°C]) across much of New Brunswick. In contrast, the presence of H. leporispalustris, which is a competent vector of tularaemia, was significantly (P < 0.05) associated with specific ranges of mean DD > 0°C, mean annual precipitation, percentage of clay in site soil, elevation and season in a multivariable logistic regression model. With the exception of some localized areas, temperature conditions and deer density may be too low for the establishment of I. scapularis and Lyme disease risk areas in New Brunswick, while environmental conditions were suitable for H. leporispalustris at many sites. These findings indicate differing ecological niches for two tick species of public health significance.
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Affiliation(s)
- Vanessa Gabriele-Rivet
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
| | - Julie Arsenault
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
| | - Jacqueline Badcock
- Office of the Chief Medical Officer of Health, New Brunswick Department of Health, Fredericton, New Brunswick, Canada
| | | | - Jim Edsall
- Jim Edsall Insect Identification Services, Dartmouth, Nova Scotia, Canada
| | - Jim Goltz
- New Brunswick Department of Aquaculture, Agriculture & Food, Fredericton, New Brunswick, Canada
| | - Joe Kennedy
- New Brunswick Natural Resources, Fredericton, New Brunswick, Canada
| | - L. Robbin Lindsay
- Public Health Agency of Canada, National Microbiology Laboratory, Winnipeg, Manitoba, Canada
| | - Yann Pelcat
- Public Health Agency of Canada, Laboratory for Foodborne Zoonoses, Saint-Hyacinthe, Québec, Canada
| | - Nicholas H. Ogden
- Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
- Public Health Agency of Canada, Laboratory for Foodborne Zoonoses, Saint-Hyacinthe, Québec, Canada
- * E-mail:
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181
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Belkahia H, Ben Said M, Alberti A, Abdi K, Issaoui Z, Hattab D, Gharbi M, Messadi L. First molecular survey and novel genetic variants' identification of Anaplasma marginale, A. centrale and A. bovis in cattle from Tunisia. INFECTION GENETICS AND EVOLUTION 2015; 34:361-71. [PMID: 26117444 DOI: 10.1016/j.meegid.2015.06.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/26/2015] [Accepted: 06/15/2015] [Indexed: 01/23/2023]
Abstract
Few data are available about the presence and distribution of Anaplasma species in cattle in North African countries. In this study prevalence, co-infections, risk factors and genetic diversity of Anaplasma species were evaluated in bovines from Northern Tunisia. A total of 232 cattle from 36 randomly selected farms in three Tunisian localities were investigated for the presence of Anaplasma species in blood by Real-time PCR and/or nested PCR. Overall infection rates of Anaplasma spp., Anaplasma marginale, Anaplasma centrale and Anaplasma bovis were 34.9%, 25.4%, 15.1%, and 3.9%, respectively. Anaplasma phagocytophilum was not detected in cattle. The most common co-infection pattern was an association of A. marginale and A. centrale (11.2%). Five cattle (2.1%) all reared in the sub-humid bioclimatic area, were co-infected by the three Anaplasma species. Molecular prevalence of Anaplasma infection varied significantly according to locality, bioclimatic area, tick infestation and type of breeding. Animals of the Holstein breed were less infected by A. marginale and A. centrale than other breeds. Genetic analysis of A. marginale msp4 gene indicated a high sequence diversity of Tunisian strains, suggesting a multiple introduction of infected cattle from different origins. Phylogenetic studies based on the 16S rRNA gene showed that the most prevalent A. centrale strains were closely related to the A. centrale vaccine strain. Moreover, all A. bovis variants clustered with other A. bovis sequences obtained from domestic and wild ruminant strains. This is the first molecular investigation on Anaplasma species in Tunisian cattle providing pivotal background for designing epidemiological studies and to develop control strategies in the country.
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Affiliation(s)
- Hanène Belkahia
- Laboratoire de Microbiologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia; Faculté des Sciences de Bizerte, Université de Carthage, 7021 Jarzouna, Tunisia
| | - Mourad Ben Said
- Laboratoire de Microbiologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia
| | - Alberto Alberti
- Dipartimento di Medicina Veterinaria, Università degli Studi di Sassari, Sassari, Italy
| | - Khaoula Abdi
- Laboratoire de Biotechnologie et Valorisation des Bio-Géo Ressources, Institut Supérieur de Biotechnologie de Sidi Thabet, Université de La Manouba, 2020 Sidi Thabet, Tunisia
| | - Zakia Issaoui
- Laboratoire de Microbiologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia
| | - Dorra Hattab
- Laboratoire de Microbiologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia
| | - Mohamed Gharbi
- Laboratoire de Parasitologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia
| | - Lilia Messadi
- Laboratoire de Microbiologie, Ecole Nationale de Médecine Vétérinaire, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de La Manouba, 2020 Sidi Thabet, Tunisia.
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182
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Ogden NH, Barker IK, Francis CM, Heagy A, Lindsay LR, Hobson KA. How far north are migrant birds transporting the tick Ixodes scapularis in Canada? Insights from stable hydrogen isotope analyses of feathers. Ticks Tick Borne Dis 2015; 6:715-20. [PMID: 26100493 DOI: 10.1016/j.ttbdis.2015.06.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 05/15/2015] [Accepted: 06/09/2015] [Indexed: 10/23/2022]
Abstract
Lyme disease is emerging in Canada because of northward range expansion of the tick vector Ixodes scapularis. It is hypothesised that I. scapularis feeding on passerine birds migrating north in spring are important in founding new I. scapularis populations leading to northward range expansion. However, there are no studies on how far north I. scapularis may be carried, only inferences from passive tick surveillance. We used stable hydrogen isotope (δ(2)H) analysis of rectrices collected from northward migrating, I. scapularis-carrying, passerine birds captured in Canada to estimate how far north I. scapularis may be carried. Rectrices are usually grown close to breeding sites and their δ(2)H values reflect those in the environment, which vary strongly with latitude in North America. Passerines usually return to their breeding or natal sites so δ(2)H values of rectrices of northward migrating birds can identify the likely latitudinal bands of their intended destinations. In 2006 we analysed δ(2)H from rectrices of 73 I. scapularis-carrying birds captured at five migration monitoring stations, mainly from southern Ontario. Values of δ(2)H ranged from -33 to -124‰, suggesting 19/71 (26.7%) birds were destined for latitude band B (the most southerly part of Ontario), 40/71 (56.3%) birds were destined for band C (which extends from southern Ontario, Quebec and the Maritimes to southern James Bay) and 12/71 (16.9%) birds were destined for bands D and E (which extend from northern Ontario and Quebec into the southern Canadian Arctic). This indicates that many I. scapularis-carrying migratory birds in spring have destinations far north in Canada, including some farther north than the current region of climatic suitability for I. scapularis. These findings support the hypothesis that I. scapularis may continue to be spread north by spring migrating passerines. Some thrush species may be particularly implicated in far northward dispersion of I. scapularis.
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Affiliation(s)
- N H Ogden
- National Microbiology Laboratory, Public Health Agency of Canada, Saint Hyacinth, QC, Canada; Groupe de Recherche en Épidémiologie des Zoonoses et Santé Publique (GREZOSP), 3200 Sicotte, Saint-Hyacinthe, QC, Canada J2S 7C6.
| | - I K Barker
- Canadian Wildlife Health Cooperative, Department of Pathobiology, Ontario Veterinary College, University of Guelph, 50 Stone Road, Guelph, ON, Canada N1G 2W1.
| | - C M Francis
- Canadian Wildlife Service, Environment Canada, 1125 Colonel By, Ottawa, ON, Canada K1A 0H3.
| | - A Heagy
- Bird Studies Canada, 115 Front St., Port Rowan, ON, Canada N0E 1M0.
| | - L R Lindsay
- Zoonotic Diseases & Special Pathogens Division, Public Health Agency of Canada, National Microbiology Laboratory, 1015 Arlington Street, Winnipeg, MB, Canada R3E 3R2.
| | - K A Hobson
- Environment Canada, 11 Innovation Blvd, Saskatoon, SK, Canada S7N 3H5.
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183
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Major emerging vector-borne zoonotic diseases of public health importance in Canada. Emerg Microbes Infect 2015; 4:e33. [PMID: 26954882 PMCID: PMC4773043 DOI: 10.1038/emi.2015.33] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/22/2015] [Accepted: 05/06/2015] [Indexed: 12/25/2022]
Abstract
In Canada, the emergence of vector-borne diseases may occur via international movement and subsequent establishment of vectors and pathogens, or via northward spread from endemic areas in the USA. Re-emergence of endemic vector-borne diseases may occur due to climate-driven changes to their geographic range and ecology. Lyme disease, West Nile virus (WNV), and other vector-borne diseases were identified as priority emerging non-enteric zoonoses in Canada in a prioritization exercise conducted by public health stakeholders in 2013. We review and present the state of knowledge on the public health importance of these high priority emerging vector-borne diseases in Canada. Lyme disease is emerging in Canada due to range expansion of the tick vector, which also signals concern for the emergence of human granulocytic anaplasmosis, babesiosis, and Powassan virus. WNV has been established in Canada since 2001, with epidemics of varying intensity in following years linked to climatic drivers. Eastern equine encephalitis virus, Jamestown Canyon virus, snowshoe hare virus, and Cache Valley virus are other mosquito-borne viruses endemic to Canada with the potential for human health impact. Increased surveillance for emerging pathogens and vectors and coordinated efforts among sectors and jurisdictions will aid in early detection and timely public health response.
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184
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Ogden NH, Koffi JK, Lindsay LR, Fleming S, Mombourquette DC, Sanford C, Badcock J, Gad RR, Jain-Sheehan N, Moore S, Russell C, Hobbs L, Baydack R, Graham-Derham S, Lachance L, Simmonds K, Scott AN. Surveillance for Lyme disease in Canada, 2009 to 2012. CANADA COMMUNICABLE DISEASE REPORT = RELEVE DES MALADIES TRANSMISSIBLES AU CANADA 2015; 41:132-145. [PMID: 29769945 PMCID: PMC5933887 DOI: 10.14745/ccdr.v41i06a03] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES To summarize the first four years of national surveillance for Lyme disease in Canada from 2009 to 2012 and to conduct a preliminary comparison of presenting clinical manifestations in Canada and the United States. METHODS The numbers and incidence of reported cases by province, month, year, age and sex were calculated. Logistic regression was used to examine trends over time. Acquisition locations were mapped and presenting clinical manifestations reported for jurisdictions where data was available. Variations by province, year, age and sex as well as presenting clinical symptoms were explored by logistic regression. An initial comparative analysis was made of presenting symptoms in Canada and the United States. RESULTS The numbers of reported cases rose significantly from 144 in 2009 to 338 in 2012 (coefficient = 0.34, standard error = 0.07, P <0.05), mostly due to an increased incidence of infections acquired in Canada. More cases were classified as 'confirmed' (71.5%) than 'probable' (28.5%). Most cases occurred in locations where vector tick populations were known to be present. More men than women were affected (53.4% versus 46.6%), incidence was highest in adults aged 55 to 74 years and in children aged five to 14 years. Most cases (95%) were acquired from April to November. Of cases acquired in endemic areas, 39.7% presented with manifestations of early Lyme disease, while 60.3% had manifestations of disseminated Lyme disease. There were significant differences among age groups, sexes and provinces in the frequencies of reported clinical manifestations. The proportion of cases acquired in endemic areas presenting with early Lyme disease was lower than that reported in the US. CONCLUSION Lyme disease incidence is increasing in Canada. Most cases are acquired where vector tick populations are spreading and this varies geographically within and among provinces. There is also variation in the frequency of age, season and presenting manifestations. The lower proportion of cases presenting with early Lyme disease in Canada compared with the US suggests lower awareness of early Lyme disease in Canada, but this requires further study.
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Affiliation(s)
- NH Ogden
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - JK Koffi
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - LR Lindsay
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB
| | - S Fleming
- Public Health Branch, Nova Scotia Department of Health and Wellness, Halifax, NS
| | - DC Mombourquette
- Public Health Branch, Nova Scotia Department of Health and Wellness, Halifax, NS
| | - C Sanford
- Population Health Assessment and Surveillance, Prince Edward Island Department of Health and Wellness, Charlottetown, PE
| | - J Badcock
- Office of the Chief Medical Officer of Health, New Brunswick Department of Health, NB
| | - RR Gad
- Office of the Chief Medical Officer of Health, New Brunswick Department of Health, NB
| | - N Jain-Sheehan
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - S Moore
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - C Russell
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - L Hobbs
- Enteric, Zoonotic and Vector-Borne Diseases, Public Health Ontario, Toronto, ON
| | - R Baydack
- Communicable Disease Control Branch, Manitoba Health Healthy Living and Seniors, Winnipeg, MB
| | - S Graham-Derham
- Communicable Disease Control Branch, Manitoba Health Healthy Living and Seniors, Winnipeg, MB
| | - L Lachance
- Surveillance and Assessment Branch, Alberta Health, Calgary, AB
| | - K Simmonds
- Surveillance and Assessment Branch, Alberta Health, Calgary, AB
| | - AN Scott
- Surveillance and Assessment Branch, Alberta Health, Calgary, AB
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185
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Schvartz G, Epp T, Burgess HJ, Chilton NB, Pearl DL, Lohmann KL. Seroprevalence of equine granulocytic anaplasmosis and lyme borreliosis in Canada as determined by a point-of-care enzyme-linked immunosorbent assay (ELISA). THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 2015; 56:575-580. [PMID: 26028677 PMCID: PMC4431153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Equine granulocytic anaplasmosis (EGA) and Lyme borreliosis (LB) are an emerging concern in Canada. We estimated the seroprevalence of EGA and equine LB by testing 376 convenience serum samples from 3 provinces using a point-of-care SNAP(®) 4Dx(®) ELISA (IDEXX Laboratories, Westbrook, Maine, USA), and investigated the agreement between the point-of-care ELISA and laboratory-based serologic tests. The estimated seroprevalence for EGA was 0.53% overall (0.49% in Saskatchewan, 0.71% in Manitoba), while the estimated seroprevalence for LB was 1.6% overall (0.49% in Saskatchewan, 2.86% in Manitoba). There was limited agreement between the point-of-care ELISA and an indirect fluorescent antibody test for EGA (kappa 0.1, PABAK 0.47) and an ELISA/Western blot combination for LB (kappa 0.23, PABAK 0.71). While the SNAP(®) 4Dx(®) ELISA yielded expected seroprevalence estimates, further evaluation of serologic tests for the purposes of disease exposure recognition may be needed.
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Affiliation(s)
- Gili Schvartz
- Address all correspondence to Dr. Gili Schvartz: e-mail:
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186
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Medlin JS, Cohen JI, Beck DL. Vector potential and population dynamics for Amblyomma inornatum. Ticks Tick Borne Dis 2015; 6:463-72. [PMID: 25881916 DOI: 10.1016/j.ttbdis.2015.03.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 03/09/2015] [Accepted: 03/18/2015] [Indexed: 11/17/2022]
Abstract
We studied the natural life cycle of Amblyomma inornatum and its vector potential in South Texas. This tick is distributed throughout South Texas and most of Central America. A. inornatum represented 1.91% of the ticks collected by carbon dioxide traps during a study of free-living ticks in the Tamaulipan Biotic Province in South Texas. The life cycle of A. inornatum in South Texas showed a clear seasonal pattern consistent with one generation per year. Nymphs emerged in the spring with a peak in February through May. Adults emerged in the summer with a peak in July through September. Detection of A. inornatum larvae was negatively correlated with saturation deficit and positively correlated with rain in the previous few months. Adult activity was positively correlated with temperature and rain in the previous five weeks. Using PCR we detected the presence of species related to Candidatus Borrelia lonestari, Borrelia burgdorferi, Rickettsia species (Candidatus Rickettsia amblyommii), Ehrlichia chaffeensis, and another Ehrlichia related to Ehrlichia ewingii. Finally we sequenced the mitochondrial 16S rRNA genes and found that A. inornatum is most closely related to Amblyomma parvum. This is the first report of the life cycle, vector potential and phylogeny of A. inornatum.
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Affiliation(s)
- Jennifer S Medlin
- Department of Biology and Chemistry, Texas A&M International University, Laredo, TX 78043, United States
| | - James I Cohen
- Department of Applied Biology, Kettering University, Flint, MI 48504, United States
| | - David L Beck
- Department of Biology, Tennessee Technological University, Cookeville, TN 38506, United States.
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187
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Krakowetz CN, Sproat A, Lindsay LR, Chilton NB. Sequence variability in the mitochondrial 12S rRNA and tRNA Val genes of Ixodes scapularis (Acari: Ixodidae) individuals shown previously to be genetically invariant. Mol Cell Probes 2015; 29:177-81. [PMID: 25863143 DOI: 10.1016/j.mcp.2015.03.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 03/31/2015] [Accepted: 03/31/2015] [Indexed: 10/23/2022]
Abstract
The DNA sequences of the mitochondrial (mt) 12S rRNA and tRNA(Val) genes were characterized for 82 blacklegged ticks (Ixodes scapularis) that were genetically identical for Domains IV and V of the mt 16S rRNA gene. Thirty-one haplotypes, differed in sequence by 1-9 bp, were detected among the 82 ticks. Most nucleotide alterations in DNA sequence did not affect the stability of the secondary structures of the RNAs. The magnitude of the DNA sequence variation in the mt 12S rRNA and tRNA(Val) genes among blacklegged ticks suggests that this region of the mitochondrial genome has potential as a genetic marker for examining the population genetics and phylogeography of I. scapularis.
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Affiliation(s)
- Chantel N Krakowetz
- Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - Allison Sproat
- Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - L Robbin Lindsay
- Public Health Agency of Canada, National Microbiology Laboratory, Winnipeg, MB R3E 3R2, Canada
| | - Neil B Chilton
- Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada.
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188
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Parasite prevalence corresponds to host life history in a diverse assemblage of afrotropical birds and haemosporidian parasites. PLoS One 2015; 10:e0121254. [PMID: 25853491 PMCID: PMC4390322 DOI: 10.1371/journal.pone.0121254] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 01/29/2015] [Indexed: 11/19/2022] Open
Abstract
Avian host life history traits have been hypothesized to predict rates of infection by haemosporidian parasites. Using molecular techniques, we tested this hypothesis for parasites from three haemosporidian genera (Plasmodium, Haemoproteus, and Leucocytozoon) collected from a diverse sampling of birds in northern Malawi. We found that host life history traits were significantly associated with parasitism rates by all three parasite genera. Nest type and nest location predicted infection probability for all three parasite genera, whereas flocking behavior is an important predictor of Plasmodium and Haemoproteus infection and habitat is an important predictor of Leucocytozoon infection. Parasite prevalence was 79.1% across all individuals sampled, higher than that reported for comparable studies from any other region of the world. Parasite diversity was also exceptionally high, with 248 parasite cytochrome b lineages identified from 152 host species. A large proportion of Plasmodium, Haemoproteus, and Leucocytozoon parasite DNA sequences identified in this study represent new, previously undocumented lineages (n = 201; 81% of total identified) based on BLAST queries against the avian malaria database, MalAvi.
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189
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Schneider SC, Parker CM, Miller JR, Page Fredericks L, Allan BF. Assessing the Contribution of Songbirds to the Movement of Ticks and Borrelia burgdorferi in the Midwestern United States During Fall Migration. ECOHEALTH 2015; 12:164-73. [PMID: 25297819 DOI: 10.1007/s10393-014-0982-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 09/16/2014] [Accepted: 09/16/2014] [Indexed: 05/09/2023]
Abstract
The geographic distributions of Ixodes scapularis (black-legged tick) and the bacterium Borrelia burgdorferi (the causative agent of Lyme disease) are expanding in the USA. To assess the role of migratory songbirds in the spread of this tick and pathogen, we captured passerines in central Illinois during the fall of 2012. We compared forested sites in regions where I. scapularis populations were either previously or not yet established. Ticks were removed from birds and blood samples were taken from select avian species. Ticks were identified by morphology and molecular techniques were used to detect B. burgdorferi and other tick-borne pathogens in ticks and avian blood samples. Ixodes spp. were detected on 10 of 196 migrants (5.1%), with I. scapularis larvae found on 2 individuals. Borrelia burgdorferi sensu stricto was detected in the blood of 9 of 29 birds sampled (31%), yet only 1 infected bird was infested by ticks. The ticks were mostly Haemaphysalis leporispalustris and I. dentatus larvae, and none tested positive for B. burgdorferi. Infestation of birds by Ixodes spp. differed significantly by region, while B. burgdorferi infection did not. These data suggest that migratory birds may play a larger role in the dispersal of B. burgdorferi than previously realized.
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Affiliation(s)
- Sarah C Schneider
- Program in Ecology, Evolution, and Conservation Biology, University of Illinois, Urbana, USA
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190
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Impact of biodiversity and seasonality on Lyme-pathogen transmission. Theor Biol Med Model 2014; 11:50. [PMID: 25432469 PMCID: PMC4396072 DOI: 10.1186/1742-4682-11-50] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 10/22/2014] [Indexed: 12/30/2022] Open
Abstract
Lyme disease imposes increasing global public health challenges. To better understand the joint effects of seasonal temperature variation and host community composition on the pathogen transmission, a stage-structured periodic model is proposed by integrating seasonal tick development and activity, multiple host species and complex pathogen transmission routes between ticks and reservoirs. Two thresholds, one for tick population dynamics and the other for Lyme-pathogen transmission dynamics, are identified and shown to fully classify the long-term outcomes of the tick invasion and disease persistence. Seeding with the realistic parameters, the tick reproduction threshold and Lyme disease spread threshold are estimated to illustrate the joint effects of the climate change and host community diversity on the pattern of Lyme disease risk. It is shown that climate warming can amplify the disease risk and slightly change the seasonality of disease risk. Both the "dilution effect" and "amplification effect" are observed by feeding the model with different possible alternative hosts. Therefore, the relationship between the host community biodiversity and disease risk varies, calling for more accurate measurements on the local environment, both biotic and abiotic such as the temperature and the host community composition.
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191
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Krakowetz CN, Lindsay LR, Chilton NB. Genetic variation in the mitochondrial 16S ribosomal RNA gene of Ixodes scapularis (Acari: Ixodidae). Parasit Vectors 2014; 7:530. [PMID: 25430547 PMCID: PMC4258262 DOI: 10.1186/s13071-014-0530-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 11/07/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Ixodes scapularis is a vector of several human pathogens in the United States, and there is geographical variation in the relative number of persons infected with these pathogens. Geographically isolated populations of I. scapularis have established or are in the process of establishing in southern Canada. Knowledge of the genetic variation within and among these populations may provide insight into their geographical origins in the United States and the potential risk of exposure of Canadians to the different pathogens carried by I. scapularis. METHODS Part of the mitochondrial (mt) 16S ribosomal (r) RNA gene was amplified by PCR from 582 ticks collected from southern Canada, and Minnesota and Rhode Island in the United States. Sequence variation was examined in relation to the predicted secondary structure of the gene. Genetic diversity among populations was also determined. RESULTS DNA sequence analyses revealed 52 haplotypes. Most mutational alterations in DNA sequence occurred at unpaired sites or represented partial compensatory base pair changes that maintained the stability of the secondary structure. Significant genetic variation was detected within and among populations in different geographical regions. A greater proportion of the haplotypes of I. scapularis from the Canadian Prairie Provinces were found in the Midwest of the United States than in other regions, whereas more of the haplotypes of I. scapularis from the Canadian Central and Atlantic Provinces occurred in the Northeast of the United States. Nonetheless, 58% of I. scapularis were of a haplotype that occurs in the Midwest and Northeast of the United States; thus, their geographical origins could not be determined. CONCLUSIONS There is considerable genetic variation in the mt 16S rRNA gene of I. scapularis. There is some evidence to support the hypothesis that some lineages of I. scapularis in the Atlantic and Central Provinces of Canada may be derived from colonizing individuals originating in the Northeast of the United States, whereas those in the Prairie Provinces may be derived from individuals originating in the Midwest of the United States. However, additional genetic markers are needed to test hypotheses concerning the geographical origins of I. scapularis in Canada.
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Affiliation(s)
- Chantel N Krakowetz
- Department of Biology, University of Saskatchewan, Saskatoon, SK, S7N 5E2, Canada.
| | - L Robbin Lindsay
- Public Health Agency of Canada, National Microbiology Laboratory, Winnipeg, MB, R3E 3R2, Canada.
| | - Neil B Chilton
- Department of Biology, University of Saskatchewan, Saskatoon, SK, S7N 5E2, Canada.
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192
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The Western progression of lyme disease: infectious and Nonclonal Borrelia burgdorferi Sensu Lato populations in Grand Forks County, North Dakota. Appl Environ Microbiol 2014; 81:48-58. [PMID: 25304515 DOI: 10.1128/aem.02422-14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Scant attention has been paid to Lyme disease, Borrelia burgdorferi, Ixodes scapularis, or reservoirs in eastern North Dakota despite the fact that it borders high-risk counties in Minnesota. Recent reports of B. burgdorferi and I. scapularis in North Dakota, however, prompted a more detailed examination. Spirochetes cultured from the hearts of five rodents trapped in Grand Forks County, ND, were identified as B. burgdorferi sensu lato through sequence analyses of the 16S rRNA gene, the 16S rRNA gene-ileT intergenic spacer region, flaB, ospA, ospC, and p66. OspC typing revealed the presence of groups A, B, E, F, L, and I. Two rodents were concurrently carrying multiple OspC types. Multilocus sequence typing suggested the eastern North Dakota strains are most closely related to those found in neighboring regions of the upper Midwest and Canada. BALB/c mice were infected with B. burgdorferi isolate M3 (OspC group B) by needle inoculation or tick bite. Tibiotarsal joints and ear pinnae were culture positive, and B. burgdorferi M3 was detected by quantitative PCR (qPCR) in the tibiotarsal joints, hearts, and ear pinnae of infected mice. Uninfected larval I. scapularis ticks were able to acquire B. burgdorferi M3 from infected mice; M3 was maintained in I. scapularis during the molt from larva to nymph; and further, M3 was transmitted from infected I. scapularis nymphs to naive mice, as evidenced by cultures and qPCR analyses. These results demonstrate that isolate M3 is capable of disseminated infection by both artificial and natural routes of infection. This study confirms the presence of unique (nonclonal) and infectious B. burgdorferi populations in eastern North Dakota.
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193
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Vuong HB, Canham CD, Fonseca DM, Brisson D, Morin PJ, Smouse PE, Ostfeld RS. Occurrence and transmission efficiencies of Borrelia burgdorferi ospC types in avian and mammalian wildlife. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2014; 27:594-600. [PMID: 24382473 PMCID: PMC4180015 DOI: 10.1016/j.meegid.2013.12.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 12/18/2013] [Accepted: 12/20/2013] [Indexed: 12/11/2022]
Abstract
Borrelia burgdorferi s.s., the bacterium that causes Lyme disease in North America, circulates among a suite of vertebrate hosts and their tick vector. The bacterium can be differentiated at the outer surface protein C (ospC) locus into 25 genotypes. Wildlife hosts can be infected with a suite of ospC types but knowledge on the transmission efficiencies of these naturally infected hosts to ticks is still lacking. To evaluate the occupancy and detection of ospC types in wildlife hosts, we adapted a likelihood-based species patch occupancy model to test for the occurrence probabilities (ψ - "occupancy") and transmission efficiencies (ε - "detection") of each ospC type. We detected differences in ospC occurrence and transmission efficiencies from the null models with HIS (human invasive strains) types A and K having the highest occurrence estimates, but both HIS and non-HIS types having high transmission efficiencies. We also examined ospC frequency patterns with respect to strains known to be invasive in humans across the host species and phylogenetic groups. We found that shrews and to a lesser extent, birds, were important host groups supporting relatively greater frequencies of HIS to non-HIS types. This novel method of simultaneously assessing occurrence and transmission of ospC types provides a powerful tool in assessing disease risk at the genotypic level in naturally infected wildlife hosts and offers the opportunity to examine disease risk at the community level.
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Affiliation(s)
- Holly B Vuong
- Rutgers University, Ecology and Evolution Graduate Program, Cook Campus, ENR 1st Floor, New Brunswick, NJ 08901, USA; Cary Institute of Ecosystem Studies, 2801 Sharon Turnpike, Millbrook, NY 12545, USA.
| | - Charles D Canham
- Cary Institute of Ecosystem Studies, 2801 Sharon Turnpike, Millbrook, NY 12545, USA.
| | - Dina M Fonseca
- Rutgers University, Ecology and Evolution Graduate Program, Cook Campus, ENR 1st Floor, New Brunswick, NJ 08901, USA; Rutgers University, Center for Vector Biology, 180 Jones Ave., New Brunswick, NJ 08901, USA.
| | - Dustin Brisson
- University of Pennsylvania, Department of Biology, 209 Leidy Laboratories, Philadelphia, PA 19104, USA.
| | - Peter J Morin
- Rutgers University, Ecology and Evolution Graduate Program, Cook Campus, ENR 1st Floor, New Brunswick, NJ 08901, USA.
| | - Peter E Smouse
- Rutgers University, Ecology and Evolution Graduate Program, Cook Campus, ENR 1st Floor, New Brunswick, NJ 08901, USA.
| | - Richard S Ostfeld
- Cary Institute of Ecosystem Studies, 2801 Sharon Turnpike, Millbrook, NY 12545, USA.
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194
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Nelder MP, Russell C, Lindsay LR, Dhar B, Patel SN, Johnson S, Moore S, Kristjanson E, Li Y, Ralevski F. Population-based passive tick surveillance and detection of expanding foci of blacklegged ticks Ixodes scapularis and the Lyme disease agent Borrelia burgdorferi in Ontario, Canada. PLoS One 2014; 9:e105358. [PMID: 25171252 PMCID: PMC4149368 DOI: 10.1371/journal.pone.0105358] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 07/23/2014] [Indexed: 11/18/2022] Open
Abstract
We identified ticks submitted by the public from 2008 through 2012 in Ontario, Canada, and tested blacklegged ticks Ixodes scapularis for Borrelia burgdorferi and Anaplasma phagocytophilum. Among the 18 species of ticks identified, I. scapularis, Dermacentor variabilis, Ixodes cookei and Amblyomma americanum represented 98.1% of the 14,369 ticks submitted. Rates of blacklegged tick submission per 100,000 population were highest in Ontario's Eastern region; D. variabilis in Central West and Eastern regions; I. cookei in Eastern and South West regions; and A. americanum had a scattered distribution. Rates of blacklegged tick submission per 100,000 population were highest from children (0-9 years old) and older adults (55-74 years old). In two health units in the Eastern region (i.e., Leeds, Grenville & Lanark District and Kingston-Frontenac and Lennox & Addington), the rate of submission for engorged and B. burgdorferi-positive blacklegged ticks was 47× higher than the rest of Ontario. Rate of spread for blacklegged ticks was relatively faster and across a larger geographic area along the northern shore of Lake Ontario/St. Lawrence River, compared with slower spread from isolated populations along the northern shore of Lake Erie. The infection prevalence of B. burgdorferi in blacklegged ticks increased in Ontario over the study period from 8.4% in 2008 to 19.1% in 2012. The prevalence of B. burgdorferi-positive blacklegged ticks increased yearly during the surveillance period and, while increases were not uniform across all regions, increases were greatest in the Central West region, followed by Eastern and South West regions. The overall infection prevalence of A. phagocytophilum in blacklegged ticks was 0.3%. This study provides essential information on ticks of medical importance in Ontario, and identifies demographic and geographic areas for focused public education on the prevention of tick bites and tick-borne diseases.
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Affiliation(s)
- Mark P. Nelder
- Enteric, Zoonotic and Vector-Borne Diseases, Communicable and Infectious Disease Prevention and Control, Public Health Ontario, Toronto, Ontario, Canada
| | - Curtis Russell
- Enteric, Zoonotic and Vector-Borne Diseases, Communicable and Infectious Disease Prevention and Control, Public Health Ontario, Toronto, Ontario, Canada
| | - L. Robbin Lindsay
- Field Studies, Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Badal Dhar
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, Ontario
| | - Samir N. Patel
- Public Health Ontario Laboratory - Toronto, Public Health Ontario, Toronto, Ontario
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario
| | - Steven Johnson
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, Ontario
| | - Stephen Moore
- Enteric, Zoonotic and Vector-Borne Diseases, Communicable and Infectious Disease Prevention and Control, Public Health Ontario, Toronto, Ontario, Canada
| | - Erik Kristjanson
- Public Health Ontario Laboratory - Toronto, Public Health Ontario, Toronto, Ontario
| | - Ye Li
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, Ontario
- Dalla Lana School of Public Health, Toronto, Ontario
| | - Filip Ralevski
- Public Health Ontario Laboratory - Toronto, Public Health Ontario, Toronto, Ontario
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195
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Schramm F, Gauthier-Clerc M, Fournier JC, McCoy KD, Barthel C, Postic D, Handrich Y, Le Maho Y, Jaulhac B. First detection of Borrelia burgdorferi sensu lato DNA in king penguins (Aptenodytes patagonicus halli). Ticks Tick Borne Dis 2014; 5:939-42. [PMID: 25150726 DOI: 10.1016/j.ttbdis.2014.07.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 11/17/2022]
Abstract
The hard tick Ixodes uriae parasitises a wide range of seabird species in the circumpolar areas of both Northern and Southern hemispheres and has been shown to be infected with Borrelia burgdorferi sensu lato, the bacterial agents of Lyme borreliosis. Although it is assumed that seabirds represent viable reservoir hosts, direct demonstrations of infection are limited to a single study from the Northern hemisphere. Here, the blood of 50 tick-infested adult king penguins (Aptenodytes patagonicus halli) breeding in the Crozet Archipelago (Southern Indian Ocean) was examined for B. burgdorferi sl exposure by serology and for spirochetemia by in vitro DNA amplification. Four birds were found positive by serology, whereas B. burgdorferi sl DNA was detected in two other birds. Our data therefore provide the first direct proof of Borrelia burgdorferi sl spirochetes in seabirds of the Southern hemisphere and indicate a possible reservoir role for king penguins in the natural maintenance of this bacterium. Although the bacterial genetic diversity present in these hosts and the infectious period for tick vectors remain to be elucidated, our results add to a growing body of knowledge on the contribution of seabirds to the complex epizootiology of Lyme disease and the global dissemination of B. burgdorferi sl spirochetes.
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Affiliation(s)
- Frédéric Schramm
- Université de Strasbourg, EA 7290, Faculté de Médecine, Strasbourg, France.
| | - Michel Gauthier-Clerc
- Centre de Recherche de la Tour du Valat, Le Sambuc, Arles, France; Université de Franche-Comté, Département Chrono-Environnement, UMR UFC/CNRS 6249 USC INRA, Besançon, France
| | - Jean-Charles Fournier
- Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien, Strasbourg, France
| | - Karen D McCoy
- MIVEGEC (Maladies infectieuses et vecteurs: écologie, génétique, évolution et contrôle), UMR 5290 CNRS/IRD, UR 244 IRD UM1 UM2, Montpellier, France
| | - Cathy Barthel
- Université de Strasbourg, EA 7290, Faculté de Médecine, Strasbourg, France
| | - Danièle Postic
- Institut Pasteur, Laboratoire des Spirochètes, Paris, France
| | - Yves Handrich
- Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien, Strasbourg, France; CNRS, Institut Pluridisciplinaire Hubert Curien, Strasbourg, France
| | - Yvon Le Maho
- Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien, Strasbourg, France; CNRS, Institut Pluridisciplinaire Hubert Curien, Strasbourg, France
| | - Benoît Jaulhac
- Université de Strasbourg, EA 7290, Faculté de Médecine, Strasbourg, France
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196
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Estrada-Peña A, de la Fuente J. The ecology of ticks and epidemiology of tick-borne viral diseases. Antiviral Res 2014; 108:104-28. [DOI: 10.1016/j.antiviral.2014.05.016] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 02/08/2014] [Accepted: 05/24/2014] [Indexed: 12/30/2022]
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197
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Simon JA, Marrotte RR, Desrosiers N, Fiset J, Gaitan J, Gonzalez A, Koffi JK, Lapointe FJ, Leighton PA, Lindsay LR, Logan T, Milord F, Ogden NH, Rogic A, Roy-Dufresne E, Suter D, Tessier N, Millien V. Climate change and habitat fragmentation drive the occurrence of Borrelia burgdorferi, the agent of Lyme disease, at the northeastern limit of its distribution. Evol Appl 2014; 7:750-64. [PMID: 25469157 PMCID: PMC4227856 DOI: 10.1111/eva.12165] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 04/05/2014] [Indexed: 12/15/2022] Open
Abstract
Lyme borreliosis is rapidly emerging in Canada, and climate change is likely a key driver of the northern spread of the disease in North America. We used field and modeling approaches to predict the risk of occurrence of Borrelia burgdorferi, the bacteria causing Lyme disease in North America. We combined climatic and landscape variables to model the current and future (2050) potential distribution of the black-legged tick and the white-footed mouse at the northeastern range limit of Lyme disease and estimated a risk index for B. burgdorferi from these distributions. The risk index was mostly constrained by the distribution of the white-footed mouse, driven by winter climatic conditions. The next factor contributing to the risk index was the distribution of the black-legged tick, estimated from the temperature. Landscape variables such as forest habitat and connectivity contributed little to the risk index. We predict a further northern expansion of B. burgdorferi of approximately 250–500 km by 2050 – a rate of 3.5–11 km per year – and identify areas of rapid rise in the risk of occurrence of B. burgdorferi. Our results will improve understanding of the spread of Lyme disease and inform management strategies at the most northern limit of its distribution.
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Affiliation(s)
- Julie A Simon
- Redpath Museum, McGill University Montreal, QC, Canada
| | - Robby R Marrotte
- Redpath Museum, McGill University Montreal, QC, Canada ; Department of Biology, McGill University Montreal, QC, Canada
| | - Nathalie Desrosiers
- Ministère du Développement Durable, de l'Environnement, de la Faune et des Parcs du Québec City, QC, Canada
| | - Jessica Fiset
- Département des Sciences Biologiques, Université de Montréal Montréal, QC, Canada
| | - Jorge Gaitan
- Redpath Museum, McGill University Montreal, QC, Canada
| | - Andrew Gonzalez
- Department of Biology, McGill University Montreal, QC, Canada
| | - Jules K Koffi
- Zoonoses Division, Centre for Food-Borne, Environmental & Zoonotic Infectious Diseases, Public Health Agency of Canada Saint-Hyacinthe, QC, Canada
| | | | - Patrick A Leighton
- Groupe de recherche en épidémiologie des zoonoses et santé publique Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, QC, Canada
| | - Lindsay R Lindsay
- Zoonoses & Special Pathogens Division, National Microbiology Laboratory, Public Health Agency of Canada Winnipeg, MB, Canada
| | | | - Francois Milord
- Institut National de Santé Publique du Québec Longueuil, QC, Canada
| | - Nicholas H Ogden
- Groupe de recherche en épidémiologie des zoonoses et santé publique Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, QC, Canada
| | - Anita Rogic
- Redpath Museum, McGill University Montreal, QC, Canada ; Département des Sciences Biologiques, Université de Montréal Montréal, QC, Canada
| | | | - Daniel Suter
- Redpath Museum, McGill University Montreal, QC, Canada
| | - Nathalie Tessier
- Département des Sciences Biologiques, Université de Montréal Montréal, QC, Canada
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198
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The prevalence of Borrelia miyamotoi infection, and co-infections with other Borrelia spp. in Ixodes scapularis ticks collected in Canada. Parasit Vectors 2014; 7:183. [PMID: 24731287 PMCID: PMC4001108 DOI: 10.1186/1756-3305-7-183] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 04/02/2014] [Indexed: 11/15/2022] Open
Abstract
Background Blacklegged ticks, Ixodes scapularis are vectors of the tick-borne pathogens Borrelia burgdorferi, Anaplasma phagocytophilum and Babesia microti. Recently, the I. scapularis-borne bacterium Borrelia miyamotoi has been linked to human illness in North America. The range of this tick is expanding in Canada which may increase the potential for human exposure to these agents. Methods In this study, 4938 I. scapularis ticks collected in 2012 were tested following a newly developed PCR-based testing protocol to determine the prevalence of infection with B. miyamotoi and other pathogens in I. scapularis in Canada. Results Borrelia miyamotoi was detected in blacklegged ticks from all provinces except Newfoundland, although the infection prevalence was low (<1%). There was significant variation among provinces in the prevalence of infection of ticks with B. burgdorferi and A. phagocytophilum, but not with B. miyamotoi. Conclusions Given the widespread distribution of B. miyamotoi, infection due to this agent should be considered in patients who have been exposed to blacklegged ticks in Canada.
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199
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Dingler RJ, Wright SA, Donohue AM, Macedo PA, Foley JE. Surveillance for Ixodes pacificus and the tick-borne pathogens Anaplasma phagocytophilum and Borrelia burgdorferi in birds from California's Inner Coast Range. Ticks Tick Borne Dis 2014; 5:436-45. [PMID: 24690191 DOI: 10.1016/j.ttbdis.2014.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 02/02/2014] [Accepted: 02/06/2014] [Indexed: 11/25/2022]
Abstract
We investigated the involvement of birds in the ecology of the western black-legged tick, Ixodes pacificus, and its associated zoonotic bacteria, Borrelia burgdorferi and Anaplasma phagocytophilum, at two interior coast-range study sites in northern California. Anaplasma phagocytophilum, the agent of granulocytic anaplasmosis (GA), and B. burgdorferi s.s., the agent of Lyme disease (LD), are tick-borne pathogens that are well established in California. We screened blood and ticks from 349 individual birds in 48 species collected in 2011 and 2012 using pathogen-specific PCR. A total of 617 immature I. pacificus was collected with almost three times as many larvae than nymphs. There were 7.5 times more I. pacificus at the Napa County site compared to the Yolo County site. Two of 74 (3%) nymphal pools from an Oregon junco (Junco hyemalis) and a hermit thrush (Catharus guttatus) and 4 individual larvae (all from Oregon juncos) were PCR-positive for B. burgdorferi. Blood samples from a golden-crowned sparrow (Zonotrichia atricapilla) and a European starling (Sturnus vulgaris) were positive for A. phagocytophilum DNA at very low levels. Birds that forage on ground or bark and nest on the ground, as well as some migratory species, are at an increased risk for acquiring I. pacificus. Our findings show that birds contribute to the ecologies of LD and GA in California by serving as a blood-meal source, feeding and transporting immature I. pacificus, and sometimes as a source of Borrelia infection.
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Affiliation(s)
- Regina J Dingler
- Department of Medicine and Epidemiology, 1320 Tupper Hall, School of Veterinary Medicine, University of California, Davis, USA
| | - Stan A Wright
- Sacramento-Yolo Mosquito & Vector Control District, 8631 Bond Road, Elk Grove, CA 95624, USA
| | - Ann M Donohue
- Napa Mosquito Abatement District, 15 Melvin Road, American Canyon, CA 94503, USA
| | - Paula A Macedo
- Sacramento-Yolo Mosquito & Vector Control District, 8631 Bond Road, Elk Grove, CA 95624, USA
| | - Janet E Foley
- Department of Medicine and Epidemiology, 1320 Tupper Hall, School of Veterinary Medicine, University of California, Davis, USA.
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200
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Abstract
Efficacy of afoxolaner, a novel isoxazoline insecticide/acaricide, against Ixodes scapularis was evaluated in a laboratory study. One day prior to treatment, beagle dogs (n=16) were infested with 50 unfed wild adult ticks. Repeat infestations were performed weekly for four additional weeks. The number of live ticks remaining on each dog was determined 48 h after treatment and after each subsequent infestation. A single oral treatment with a dose approaching the minimum effective dose of afoxolaner (2.5mg/kg) eliminated the pre-existing infestations of I. scapularis ticks and controlled weekly re-infestations, with efficacy between 98% and 100% recorded until Day 23 and 94% at Day 30.
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