Lyme disease and human babesiosis are the most common tick-borne zoonoses in the Temperate Zone of North America. The number of infected patients has continued to rise globally, and these zoonoses pose a major healthcare threat. This tick-host-pathogen study was conducted to test for infectious microbes associated with Lyme disease and human babesiosis in Canada.
Comment on Schillberg, E., et al; Distribution of Ixodes scapularis in Northwestern Ontario: Results from Active and Passive Surveillance Activities in the Northwestern Health Unit Catchment Area.
Erratum 1: Schillberg et al. report an “Amblyomma cajennense” tick in central Canada . This foreign tick species lacks specific background information, including (a) history of travel, (b) date tick collected, (c) developmental life stage, (d) tick identifier, (e) identification method (molecular, morphologic), and (f) the depository. With the exception of knowing this tick was collected from a human, no other background information is available on this Amblyomma tick. The person who identified this specimen has neither been recognized in the Material and Methods section, nor named in the Author Contributions…
Presence of Babesia odocoilei and Borrelia burgdorferi Sensu Stricto in a Tick and Dual Parasitism of Amblyomma inornatum and Ixodes scapularis on a Bird in Canada
Wild birds transport ticks into Canada that harbor a diversity of zoonotic pathogens. However, medical practitioners often question how these zoonotic pathogens are present in their locality. In this study, we provide the first report of an Amblyomma inornatum tick cofeeding with a blacklegged tick, Ixodes scapularis, which parasitized a Veery, Catharus fuscescens—a neotropical songbird.
Extensive Distribution of the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, in Multiple Tick Species Parasitizing Avian and Mammalian Hosts across Canada
Lyme disease, caused by the spirochetal bacterium, Borrelia burgdorferi sensu lato (Bbsl), is typically transmitted by hard-bodied ticks (Acari: Ixodidae). Whenever this tick-borne zoonosis is mentioned in medical clinics and emergency rooms, it sparks a firestorm of controversy
Far-Reaching Dispersal of Borrelia burgdorferi Sensu Lato-Infected Blacklegged Ticks by Migratory Songbirds in Canada
Lyme disease has been documented in northern areas of Canada, but the source of the etiological bacterium, Borrelia burgdorferi sensu lato (Bbsl) has been in doubt. We collected 87 ticks from 44 songbirds during 2017, and 24 (39%) of 62 nymphs of the blacklegged tick, Ixodes scapularis, were positive for Bbsl.
Human Babesiosis Caused by Babesia duncani Has Widespread Distribution across Canada By: John D. Scott and Catherine M. Scott
Human babesiosis caused by Babesia duncani is an emerging infectious disease in Canada. This malaria-like illness is brought about by a protozoan parasite infecting red blood cells. Currently, controversy surrounds which tick species are vectors of B. duncani. Since the availability of a serological or molecular test in Canada for B. duncani has been limited, we conducted a seven-year surveillance study (2011–2017) to ascertain the occurrence and geographic distribution of B. duncani infection country-wide.
Lyme Disease Propelled by Borrelia burgdorferi-Infected Blacklegged Ticks, Wild Birds and Public Awareness ─ Not Climate Change
The blacklegged tick, Ixodes scapularis, is of major public health importance as a vector of Borrelia burgdorferi, the causal organism of Lyme disease. Migratory songbirds are involved in short- and longdistance transport of bird-feeding ticks, and play a vital role in the wide dispersal of I. scapularis and the epidemiology of Lyme disease.
We would like to applaud the author for conducting such an important study by performing a comprehensive assessment of suicide and its association with Lyme-associated diseases (LADs).1 It is the first study of its kind, and it raises a need for further investigation on this subject. Suicide is a major health care issue in the USA, contributing to almost 42,773 deaths in the USA in 2014.2 There is no data available specific to suicide associated with LAD. Dr Bransfield inferred the possible prevalence of suicide associated with LAD by an indirect method which revealed that 414,540 patients with LAD have suicidal ideation, 31,100 attempt suicide and a total of 1,244 commit suicide in the USA per year from LAD.
Background: Recent reports indicate that more than 300,000 cases of Lyme disease are diagnosed yearly in the USA. Preliminary clinical, epidemiological and immunological studies suggest that infection with the Lyme disease spirochete Borrelia burgdorferi (Bb) could be transferred from person to person via intimate human contact without a tick vector. Detecting viable Borrelia spirochetes in vaginal and seminal secretions would provide evidence to support this hypothesis.
Congenital Tick Borne Diseases: Is This An Alternative Route of Transmission of Tick-Borne Pathogens In Mammals? (2015)
Tick-borne diseases (TBDs) have become a popular topic in many medical journals. Besides the obvious participation of ticks in the transmission of pathogens that cause TBD, little is written about alternative methods of their spread. An important role is played in this process by mammals, which serve as reservoirs…
We provide the first reported case of tick paralysis in a wildlife animal caused by the western blacklegged tick, Ixodes pacificus Cooley & Kohls. Six I. pacificus females and one male were collected from a feral Snowshoe Hare roaming the coastal area of southwestern British Columbia, Canada. When the hare was rescued from the forest habitat, it was unable to walk, and showed typical symptoms of tick paralysis, including ascending flaccid paralysis. At the nearby wildlife rehabilitation centre, engorged I. pacificus females were collected from the hare….
Evidence-based guidelines for the management of patients with Lyme disease were developedby the International Lyme and Associated Diseases Society (ILADS). The guidelines address three clinical questions – the usefulness of antibiotic prophylaxis for known tick bites, the effectiveness of erythema migrans treatment and the role of antibiotic retreatment in patients with persistent manifestations of Lyme disease. Healthcare providers who evaluate and manage patients with Lyme disease are the intended users of the new ILADS guidelines, which replace those issued in 2004 (Exp Rev Anti-infect Ther 2004;2:S1–13). These clinical practice guidelines are intended to assist clinicians by presenting evidence-based treatment recommendations, which follow the Grading of Recommendations Assessment, Development and Evaluation system. ILADS guidelines are not intended to be the sole source of guidance in managing Lyme disease and they should not be viewed as a substitute for clinical judgment nor used to establish treatment protocols.
The following references for persistence of Lyme disease (Lyme borreliosis) are listed alphabetically and chronologically:
The prevalence of Borrelia miyamotoi infection, and co-infections with other Borrelia spp. in Ixodes scapularis ticks collected in Canada
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.
Predicting the speed of tick invasion: an empirical model of range expansion for the Lyme disease vector Ixodes scapularis in Canada (2012)
Over the past two decades, Ixodes scapularis, the primary tick vector of the Lyme disease pathogen Borrelia burgdorferi in North America has expanded its range northward from the USA to colonize new regions in southern Canada. We have previously projected range increases for I. scapularis based on temperature suitability, but to what extent this is matched by actual tick range expansion is unknown.
Lyme Ontario Research
First record of locally acquired human babesiosis in Canada caused by Babesia duncani: a case report
August 29, 2017
Objectives: The aim of this clinical assessment was to ascertain whether a 70-year-old Canadian patient, who had no history of out-of-country travel, had contracted a Babesia infection.
Methods: The adult human male developed constitutional symptoms, which included sweats, chills, and immobilizing fatigue, and was screened for human babesiosis. Subsequent testing included a complete Babesia panel that consisted of B. microti immunoflourescent antibody IgM and IgG, B. duncani immunofluorescent antibody IgM and IgG, Babesia PCR, and Babesia fluorescent in situ hybridization (FISH) test.
Results: Both the IgM serology and the molecular FISH RNA probe were positive for B. duncani; all tests for B. microti were negative. Based on clinical symptoms and laboratory tests, the patient was diagnosed with human babesiosis. Interestingly, the patient’s wife also was confirmed positive using serological and molecular testing.
Conclusions: This is the first report of a locally acquired case of human babesiosis in Canada caused by Babesia duncani. The geographical distribution of B. duncani in North America is much greater than previously anticipated, especially north of the Canada-United States border. Since the patient was bitten by a blacklegged tick, Ixodes scapularis, a carrier of multiple
zoonotic pathogens, the author suggests that this tick species is a vector of B. duncani. Health-care providers must be aware that B. duncani is present in Canada, and poses a public health risk.
Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, Detected in Multiple Tick Species at Kenora, Ontario, Canada
March 20th, 2017
The Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.), is typically transmitted to mammalian hosts, including humans, by ixodid (hard-bodied) ticks (Acari: Ixodidae) . Each tick species has its own set of suitable hosts, and Lyme disease, a zoonosis, is incidental to humans and domestic animals [2,3]. Left untreated or inadequately treated, Lyme disease can inflict a myriad of multisystemic clinical manifestations.
Detection of Lyme Disease Bacterium, Borrelia burgdorferi sensu lato, in Blacklegged Ticks Collected in the Grand River Valley, Ontario, Canada
February 8th, 2017
We document the presence of blacklegged ticks, Ixodes scapularis, in the Grand River valley, Centre Wellington, Ontario. Overall, 15 (36%) of 42 I. scapularis adults collected from 41 mammalian hosts (dogs, cats, humans) were positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.). Using real-time PCR testing and DNA sequencing of the flagellin (fla) gene, we determined that Borrelia amplicons extracted from I. scapularis adults belonged to B. burgdorferi sensu stricto (s.s.), which is pathogenic to humans and certain domestic animals. Based on the distribution of I. scapularis adults within the river basin, it appears likely that migratory birds provide an annual influx of I. scapularis immatures during northward spring migration. Health-care providers need to be aware that local residents can present with Lyme disease symptoms anytime during the year.
Epizootiology of the Lyme Disease Spirochete, Borrelia Burgdorferi in Blaclegged Ticks, Ixodes Scapularis and Small Mammals at Point Pelee National Park
March 31, 2000
The blacklegged tick, Ixodes scapularis has an established population at Point Pelee National Park (PPNP).
Established Population of Blacklegged Ticks with High Infection Prevalence for the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, on Corkscrew Island, Kenora District, Ontario (2016)
Published: October 27, 2016
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.
First Record of Ixodes affinis Tick (Acari: Ixodidae) Infected with Borrelia burgdorferi Sensu Lato Collected from a Migratory Songbird in Canada (2016)
Published: June, 2016
Migratory songbirds transport hard-bodied ticks (Acari: Ixodidae) into Canada during northward spring migration, and some of these bird-feeding ticks harbor a wide diversity of pathogenic microorganisms. In this study, we collected a nymphal Ixodes affinis Neumann from a Common Yellowthroat, Geothylypis trichas (Linnaeus), at Ste-Anne-de-Bellevue, Québec, and it was infected with the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.) Johnson, Schmid, Hyde, Steigerwalt & Brenner. Using PCR on this tick extract and DNA sequencing on the borrelial amplicons, we detected B. burgdorferi sensu stricto (s.s.), a genospecies that is pathogenic to people and certain domestic animals. In addition, we collected an I. affinis nymph from a Swainson’s Thrush, Catharus ustulatus (Nuttall), at Toronto, Ontario, and a co-feeding nymphal blacklegged tick, Ixodes scapularis Say, tested positive for B. burgdorferi s.s. These bird-tick findings constitute the first reports of I. affinis in Ontario and Québec and, simultaneously, the first report of a B. burgdorferi s.l.-infected I. affinis in Canada. Since Neotropical and southern temperate songbirds have a rapid flight pace, they are capable of transporting ticks infected with B. burgdorferi s.l. hundreds of kilometres to Canada. Healthcare professionals should be cognisant that migratory songbirds can transport diverse genotypes of B. burgdorferi s.l. into Canada from southern latitudes that may be missed by current Lyme disease serological tests.
Detection of Borrelia americana in the Avian Coastal Tick, Ixodes auritulus (Acari: Ixodidae), Collected from a Bird Captured in Canada (2016)
Published: July, 2016
We document the first record of Borrelia americana in Canada. This Borrelia was detected in an avian coast tick, Ixodes auritulus (Acari: Ixodidae), collected from a Varied Thrush, Ixoreus naevius, along coastal British Columbia. Using real-time PCR and DNA sequencing of the flagellin gene, we determined that the borrelial amplicon from the I. auritulus nymph was 99% homologous with B. americana type strain SCW-41. Because patients infected with B. americana can be seronegative for Lyme disease, medical professionals should be willing to pursue molecular analyses and con-ider treatment for patients with Lyme disease-like symptoms.
Published: June, 2016
Bobbi Pritt and colleagues1 reveal that Borrelia mayonii is a new member of the Borrelia burgdorferi sensu lato complex, and show that this spirochete is pathogenic to human beings. However, the authors err on several key points. They state B burgdorferi sensu stricto was previously the only cause of Lyme borreliosis in the USA. With the discovery of B mayonii, they take credit for describing the first non-B burgdorferi sensu stricto in patients in the USA; this assumption is not true. Girard and colleagues2 reported B bissettii in patients in California and Clark and colleagues3 documented B americana and B andersonii in human blood from resi dents in the southeastern USA. Further more, Rudenko and colleagues4 reported a B bissettiilike strain in a Florida patient. In all of these cases, patients had clinical symptoms commonly associated with Lyme borreliosis.
Prevalence of the Lyme Disease Spirochete, Borrelia burgdorferi, in Blacklegged Ticks, Ixodes scapularis at Hamilton-Wentworth, Ontario (2016)
Published: April 10, 2016
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.
Ticks parasitizing gallinaceous birds in Canada and first record of Borrelia burgdorferi-infected Ixodes pacificus (Acari: Ixodidae) from California Quail (2016)
Published: January 16, 2016
In far-western Canada, gallinaceous birds are hosts of hard ticks (Ixodida: Ixodidae) that can carry zoonotic pathogens. In this study, we collected the avian coastal tick, Ixodes auritulus Neumann, the western blacklegged tick, Ixodes pacificus Cooley & Kohls, and Ixodes spinipalpis Hadwen & Nuttall, from gallinaceous birds on Vancouver Island, British Columbia. Notably, we provide the first records of these three tick species on California Quail, Callipepla californica (Shaw), in Canada. We document the first records of I. auritulus parasitizing Sooty Grouse, Dendragapus fulginosis (Ridway). Moreover, we furnish the first report of I. spinipalpis on a quail. An I. pacificus nymph was collected from a California Quail, and it was positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.) Johnson, Schmid, Hyde, Steigerwalt & Brenner. Using PCR on the nymphal extract and DNA sequencing on the borrelial amplicon, we specifically detected B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. Since some ground-dwelling birds are involved in the enzootic maintenance of Lyme disease, veterinarians, wildlife rehabilitators, hunters, and health-care providers should be vigilant that gallinaceous birds may play a role in the enzootic transmission of B. burgdorferi s.l. in Canada.
Published: November 30, 2015
We document Amblyomma dissimile Koch (Acari: Ixodidae) parasitizing a bird in Canada. A partially engorged A. dissimile nymph was collected from a Veery, Catharus fuscescens (Stephens) (Passeriformes: Turdidae), in Toronto, Ontario during spring migration. This constitutes the first authentic host record of A. dissimile on a bird in North America and, likewise, on a Veery, plus a new distributional record in Canada. Veeries could theoretically transport A. dissimile from as far south as southeastern Brazil, a distance of over 7,500 km. Experimentally, A. dissimile can transmit Ehrlichia ruminantium (Ricksettiales), which causes heartwater, a severe disease of cattle and other ungulates. Since a fully engorged A. dissimile nymph could likely molt during the summer in northern latitudes, this tick species could potentially parasitize local reptiles, people or ungulates, and cause autochtonous disease. Because A. dissimile is known to harbor rickettsiae in South America and is a laboratory vector of E. ruminantium, the medical and veterinary profession must be vigilant that A. dissimile may pose a health risk.
First record of Amblyomma rotundatum tick (Acari: Ixodidae) parasitizing a bird collected in Canada (2015)
Published: February 27, 2015
Migratory birds disperse engorged ticks across Canada during northward spring migration. During our tick-host study, we collected a nymphal Amblyomma rotundatum Koch, from a Veery, Catharus fuscescens (Stephens) (Passeriformes: Turdidae), at Long Point, Ontario, Canada. In the laboratory, this nymph molted to a female in 44 d. The infestation of A. rotundatum on a Veery constitutes a first tick-host record, and a new distributional record in Canada. Notably, this novel collection is the northernmost record of A. rotundatum and the first record of this species on a bird anywhere. We provide formidable evidence that migratory songbirds can carry A. rotundatum thousands of kilometers during northward spring migration. From an epidemiological perspective, A. rotundatum is known to harbor bacteria that are pathogenic to humans. Health-care providers should take note that migratory songbirds can transport A. rotundatum into Canada, and be alert that this tick species signifies an unforeseen public health risk to humans.
New records of the Lyme disease bacterium in ticks collected from songbirds in central and eastern Canada (2015)
Published: May 5, 2015
This study highlights the collection of ticks from wild-caught birds in central and eastern Canada. Using polymerase chain reaction (PCR), 32 (33%) of 98 Ixodes species ticks tested were positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.) Johnson, Schmid, Hyde, Steigerwalt, and Brenner (hereafter B. burgdorferi). Immature blacklegged ticks, Ixodes scapularis Say, which are competent vectors of B. burgdorferi, constituted the predominant Ixodes species tick collected from parasitized songbirds; specifically, 31(35%) of 89 I. scapularis nymphs were positive for B. burgdorferi. Notably, we report the first B. burgdorferi-positive I. scapularis (nymph) on a migratory passerine in Prince Edward Island; this is the first record of a tick on a bird in this maritime province.
Infection Prevalence of Borrelia burgdorferi in Ticks Collected from Songbirds in Far-Western Canada (2015)
Published: May 28, 2015
Worldwide, wild birds play a vital role in the dispersal of ticks that harbour tick-borne pathogens, including Borrelia burgdorferi, the Lyme disease bacterium. Using PCR testing, we found 124 (31%) of 405 ticks (4 species), which were collected from 21 species of birds in far-western Canada, to be infected with B. burgdorferi. Transstadial transmission of B. burgdorferi occurred from larva to nymph, plus nymph to adult, in the avian coastal tick, Ixodes auritulus, collected from songbirds in British Columbia (B.C). Collectively, all 3 motile life stages (larva, nymph, adult) of this tick had an infection prevalence of 31% for B. burgdorferi, which suggests vector competency. A Pacific Wren was highly infested with I. auritulus immatures, and 20 (44%) of 45 ticks (2 nymphs, 43 larvae) were infected with B. burgdorferi. This heavy infestation shows the high potential to initiate a new population of ticks and to disseminate Lyme spirochetes. Epidemiologically, B. burgdorferi-in- fected I. auritulus larvae collected from the Spotted Towhee, Swainson’s Thrush, Pacific Wren, and Fox Sparrow suggest that these avian hosts act as reservoirs for B. burgdorferi. In this study, the western blacklegged tick, Ixodes pacificus, and Ixodes spinipalpis played a limited role in the enzo- otic transmission cycle of B. burgdorferi along coastal B.C. We document the first record of I. spinipalpis on a bird in Alberta. Because songbirds widely disperse Lyme disease vector ticks, primary health providers and the general public must be vigilant that outdoors people may be bitten by B. burgdorferi-infected ticks throughout far-western Canada.
Published: January 30, 2014
This 2-year study implicates migratory songbirds in the initiation of an inland Lyme disease endemic area in southeastern Ontario. The spirochetal bacterium, Borrelia burgdorferi sensu lato Johnson, Schmid, Hyde, Steigerwalt & Brenner, which causes Lyme disease, was detected in blacklegged ticks, Ixodes scapularis Say, collected by flagging. Based on PCR amplification, 19 (33.3%) of 57 I. scapularis adults (males, females) were infected with B. burgdorferi. Since transovarial transmission of B. burgdorferi is nil in I. scapularis and white-tailed deer, Odocoileus virginianus Zimmermann, are not reservoircompetent hosts, we suggest that songbirds are the mode of introduction of B. burgdorferi-infected I. scapularis. All of the natural abiotic and biotic attributes are present to establish a Lyme disease endemic area. Blacklegged ticks survived the winter successfully at the epicentre. We provide substantial evidence that migratory songbirds initially introduced Lyme disease vector ticks and B. burgdorferi spirochetes to this remote woodland habitat and initiated an established population of blacklegged ticks.
First Detection of Lyme Disease Spirochete Borrelia burgdorferi in Ticks Collected from a Raptor in Canada (2013)
During a pan-Canadian tick-host study, we detected the spirochetal bacterium, Borrelia burgdorferi sensu lato, which causes Lyme disease, in ticks collected from a raptor. Lyme disease is one of a number of zoonotic, tick-borne diseases causing morbidity and mortality worldwide. Larvae of the avian coastal tick, Ixodes auritulus, were collected by wildlife rehabilitators from a Cooper’s hawk, Accipiter ooperii, on Vancouver Island, British Columbia. Using PCR amplification of the linear plasmid ospA gene of B. burgdorferi, 4 (18%) of 22 larvae were positive. Since these engorged I. auritulus larvae had not had a previous blood meal and B. burgdorferi is rarely transmitted from infected female ticks to their progeny, we propose that Cooper’s Hawks are reservoir-competent hosts of B. burgdorferi. Our tick-host discovery provides the first report of bird-feeding ticks on a Cooper’s Hawk, and exhibits the premiere record of B. burgdorferi-positive ticks on a raptor. Not only are passerine (perching) and gallinaceous (chicken-like) birds involved in the wide dispersal of Lyme disease vector ticks, raptors are now also implicated in the dissemination of B. burgdorferiinfected ticks. Although I. auritulus does not bite humans, this tick species plays an integral role in the 4-tick enzootic cycle of B. burgdorferi along the West Coast of North America. In essence, raptors and I. auritulus ticks may help to amplify this infectious agent in nature, and increase the likelihood of people contracting Lyme disease, especially in coastal areas.
Widespread Dispersal of Borrelia Burgdorferi-Infected Ticks Collected from Songbirds Across Canada (2012)
Millions of Lyme disease vector ticks are dispersed annually by songbirds across Canada, but often overlooked as the source of infection. For clarity on vector distribution, we sampled 481 ticks (12 species and 3 undetermined ticks) from 211 songbirds (42 species/subspecies) nationwide. Using PCR, 52 (29.5%) of 176 Ixodes ticks tested were positive for the Lyme disease spirochete, Borrelia burgdorferis.l. Immature blacklegged ticks,Ixodes scapularis, collected from infested songbirds had a B. burgdorferi infection prevalence of 36% (larvae, 48%; nymphs, 31%). Notably, Ixodes affinis is reported in Canada for the first time and, similarly, Ixodes auritulus for the initial time in the Yukon. Firsts for bird-parasitizing ticks include I. scapularis in Quebec and Saskatchewan. We provide the first records of 3 tick species cofeeding on passerines (song sparrow, Swainson’s thrush). New host records reveal I. scapularis on the blackpoll warbler and Nashville warbler. We furnish the following first Canadian reports of B. burgdorferi–positive ticks: I. scapularis on chipping sparrow, house wren, indigo bunting; I. auritulus on Bewick’s wren; and I. spinipalpis on a Bewick’s wren and song sparrow. First records of B. burgdorferi–infected ticks on songbirds include the following: the rabbit-associated tick, Ixodes dentatus, in western Canada; I. scapularis in Quebec, Saskatchewan, northern New Brunswick, northern Ontario; and Ixodes spinipalpis(collected in British Columbia). The presence ofB. burgdorferi in Ixodeslarvae suggests reservoir competency in 9 passerines (Bewick’s wren, common yellowthroat, dark-eyed junco, Oregon junco, red-winged blackbird, song sparrow, Swainson’s thrush, swamp sparrow, and white-throated sparrow). We report transstadial transmission (larva to nymph) of B. burgdorferi in I. auritulus. Data suggest a possible 4-tick, i.e.,I. angustus,I. auritulus,I. pacificus, and I. spinipalpis, enzootic cycle ofB. burgdorferi on Vancouver Island, British Columbia. Our results suggest that songbirds infested with B. burgdorferi–infected ticks have the potential to start new tick populations endemic for Lyme disease. Because songbirds disperse B. burgdorferi–infected ticks outside their anticipated range, health-care providers are advised that people can contract Lyme disease locally without any history of travel.
Lyme disease is reported across Canada, but pinpointing the source of infection has been problematic. In this three-year, bird-tick-pathogen study (2004-2006), 366 ticks representing 12 species were collected from 151 songbirds (31 passerine species/subspecies) at 16 locations Canada-wide. Of the 167 ticks/pools tested, 19 (11.4%) were infected with Borrelia burgdorferi sensu lato (s.l.). Sequencing of the rrf-rrl intergenic spacer gene revealed four Borrelia genotypes: B. burgdorferi sensu stricto (s.s.) and three novel genotypes (BC genotype 1, BC genotype 2, BC genotype 3). All four genotypes were detected in spirochete-infected Ixodes auritulus (females, nymphs, larvae) suggesting this tick species is a vector for B. burgdorferi s.l. We provide first-time records for: ticks in the Yukon (north of 60° latitude), northernmost collection of Amblyomma americanum in North America, and Amblyomma imitator in Canada. First reports of bird-derived ticks infected with B. burgdorferi s.l. include: live culture of spirochetes from Ixodes pacificus (nymph) plus detection in I. auritulus nymphs, Ixodes scapularis in New Brunswick, and an I. scapularis larva in Canada. We provide the first account of B. burgdorferi s. l. in an Ixodes muris tick collected from a songbird anywhere. Congruent with previous data for the American Robin, we suggest that the Common Yellowthroat, Golden-crowned Sparrow, Song Sparrow, and Swainson’s Thrush are reservoir-competent hosts. Song Sparrows, the predominant hosts, were parasitized by I. auritulus harboring all four Borrelia genotypes. Our results show that songbirds import B. burgdorferi s.l.-infected ticks into Canada. Bird-feeding I. scapularis subadults were infected with Lyme spirochetes during both spring and fall migration in eastern Canada. Because songbirds disperse millions of infected ticks across Canada, people and domestic animals contract Lyme disease outside of the known and expected range.
First Isolation of Lyme Disease Spirochete, Borrelia burgdorferi, from Ticks Collected from Songbirds in Ontario, Canada (2009)
This study documents the first isolation of the Lyme disease spirochete, Borrelia burgdorferi, from ticks attached to songbirds in Ontario. Viable spirochetes were cultured from a nymph of the blacklegged tick, Ixodes scapularis Say, detached from a Hermit Thrush, Catharus guttatus. Similarly, B. burgdorferi isolates were obtained from I. Scapularis nymphs collected from a House Wren, Troglodytes aedon. These B. burgdorferi isolates show divergent heterogeneity indicating that some strains originated from nearby locales and others from southern latitudes. Lyme disease vector ticks are transported by northward-migrating songbirds, and dispersed widely across southern Canada. Importantly, B. burgdorferi-infected I. scapularis ticks pose a public health risk to people and domestic animals wherever they are released.
Borrelia burgdorferi sensu stricto (s.s.) was isolated from questing adult Ixodes scapularis Say ticks collected from Turkey Point Provincial Park (TPPP), Ontario, Canada during 2005-2006. DNA from ten (67%) of 15 pools of ticks was confirmed positive for B. burgdorferi s.s. using polymerase chain reaction (PCR) by targeting the rrf (5S)-rrl (23S) intergenic spacer region and OspA genes. This significant infection rate indicates an accelerated development of B. burgdorferi s.s. in TPPP, because this pathogen was not detected five years previously during sampling of the three motile life stages of I.
scapularis. Our study provides the initial report of the presence of B. burgdorferi s.s. in TPPP, which is now endemic for Lyme disease. Ultimately, people and domestic animals are at risk of contracting Lyme disease when they frequent this park.
The blacklegged tick, Ixodes scapularis Say (Acari: Ixodidae), has a wide geographical distribution in Ontario, Canada, with a detected range extending at least as far north as the 50th parallel. Our data of 591 adult I. scapularis submissions collected from domestic animals (canines, felines, and equines) and humans during a 10-yr period (1993-2002) discloses a monthly questing activity in Ontario that peaks in May and October. The Lyme disease spirochete Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt & Brenner was detected in 12.9% of I. scapularis adults collected from domestic hosts with no history of out-of-province travel or exposure at a Lyme disease endemic area. Fifty-three isolates of B. burgdorferi were confirmed positive with polymerase chaim reaction by targeting the rrf (5S)-rrl (23S) gene. Using DNA sequencing of the ribosomal species-specific rrf (5S)-rrl (23S) intergenic spacer region, all isolates belong to the pathogenic genospecies B. burgdorferi sensu stricto (s.s.). Nucleotide sequence analyses of a 218- to 220-bp amplicon fragment exhibits six cluster patterns and, collectively, these isolates branch into four phylogenetic cluster groups for both untraveled, mammalian hosts and those with travel to the northeastern United States (New Jersey and New York). Four of five geographic regions in Ontario had strain variants consisting of three different genomic cluster groups. Overall our molecular characterization of B. burgdorferi s.s. shows genetic heterogeneity within Ontario and displays and connecting link to common strains from Lyme disease endemic areas in the northeastern United States. Moreover, our findings of B. burgdorferi in I. scapularis reveal that people and domestic animals may be exposed to Lyme disease vector ticks, which have wide-ranging distribution in eastern and central Canada.
During a 3-yr comprehensive study, 196 ixodid ticks (9 species) were collected from 89 passerine birds (32 species) from 25 localities across Canada to determine the distribution of avian-associated tick species and endogenous Lyme disease spirochetes, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt, and Brenner. We report the following first records of tick parasitism on avian hosts: the rabbit-associated tick, Ixodes dentatus Marx, from Manitoba and Ontario; the mouse tick, Ixodes muris Bishopp and Smith, from British Columbia; and the blacklegged tick, Ixodes scapularis Say, from New Brunswick. Moreover, we provide the first record of the Neotropical tick, Amblyomma huinerale Koch (1 nymph), in Canada and its parasitism of any bird. This tick was compared morphologically with nymphs of other Neotropical Amblyomma spp., and genetically, using a 344-bp fragment of the 12S rDNA sequence of 41 New World Amblyomma species. The first collections of the western blacklegged tick, Ixodes pacificus Cooley and Kohls, from passerine species in Alberta and British Columbia, are also reported. Notably, we further report the first isolation of B. burgdorferi from the bird tick, Ixodes auritulus Neumann, collected from an American robin, Turdus migratorius L., on Vancouver Island. Furthermore, B. burgdorferi-positive 1. auritulus larvae were collected from a reservoir-competent fox sparrow, Passerella iliaca (Merrem). Our findings indicate that ground-dwelling pas-serines, in particular, are parasitized by certain ixodid ticks and play an important role across Canada in the wide dispersal of B. burgdorferi-infected ticks and increased risk of Lyme disease exposure.
The Lyme disease spirochete, Borrelia burgdcnferi Johnson, Schmidt, Hyde, Steigerwalt, and Brenner was discovered in blacklegged ticks, Ixodes scapularis Say at Rondeau Provincial Park, Ontario, Canada. During this 2-yr study, spirochetes were found in B. burgdolferi-positive I. scapularis larvae attached to B. burgdoiferi-infected white-footed mice, Peromyscus leucopus Rafinesque. Isolates of B. burgdorferi were cultured from blacklegged tick adults, and confirmed positive with polymerase chain reaction by targeting OspA and rif (55)-rrl (23S) genes. These findings show an endemic area for B. burgdorferi within an established population of I. scapularis at Rondeau Provincial Park.
A total of 152 ixodid ticks (Acari: Ixodidae) consisting of nine species was collected from 82 passerine birds (33 species) in 14 locations in Canada from 1996 to 2000. The Lyme disease spirochete Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwaldt & Brenner was cultured from the nymph of a blacklegged tick, Ixodes scapularis Say, that had been removed from a common yellowthroat, Geothlypis triehas L., from Bon Portage Island, Nova Scotia. As a result of bird movement, a nymphal I. scapulas-is removed from a Swainson’s thrush, Catharus ustulatus imams (Godfrey), at Slave Lake, Alberta, during spring migration becomes the new, most western and northern record of this tick species in Canada. Amblyomma longirostre Koch, Amblyomma sob anerae Stoll, and Ixodes baergi Cooley & Kohls are reported for the first time in Canada. Similarly, Amblyomma americanum L., Amblyomma maculatum Koch, and Ixodes muris Bishopp & Smith are reported for the first time on birds in Canada. After removal of an I. muris gravid female from a song sparrow, Melospiza melodia Wilson, at St. Andrews, New Brunswick, eggs were laid, which developed into larvae, and this new tick-host record demonstrates that birds have the potential to start a new tick population. We conclude that passerine birds disperse several species of ixodid ticks in Canada, and during spring migration translocate ticks from the United States, and Central and South America, some of which are infected with B. burgdorferi.
The Lyme disease spirochete, Borrelia burgdorferi, has been isolated from blacklegged ticks, Ixodes scapularis, collected at Rondeau Provincial Park. The Park is a peninsula located on the north shore of Lake Erie, in Chatham-Kent, and consists of Carolinian hardwood forest. This 3,254 hectare cuspate sandspit was formed by water currents depositing sand over several thousand years. The Park attracts high numbers of birds in the spring.
Lyme disease, the most common tick-borne disease in North America, is a multisystemic illness of humans and domestic animals caused by the spirochete Borrelia burgdolferi sensu lato (“in the broad sense”). Small mammals are the main reservoir hosts for this bacterium, and Ixodes scapularis (blacklegged tick) and Ixodes pacificus (western blacklegged tick) found in British Columbia are the principal vectors in Canada.
The Lyme disease spirochete, Borrelia burgdorferi, has been isolated from a blacklegged tick, Ixodes scapularis, removed from a songbird in Canada. On 28 May 1999, this engorged blacklegged tick nymph was removed from a common yellowthroat, Geothlypis trichas, collected during bird banding on Bon Portage Island, Nova Scotia.
The Lyme disease (LD) spirochete, Borrelia burgdorferi, has been isolated from a black-legged tick, Ixodes scapularis (northern pop-ulations formerly considered I. dammini). This is the first time that a live culture of B. burgdorferi has been isolated in the Thunder Bay District.
Borrelia burgdorferi, the causal organism of Lyme disease, has been isolated from a black-legged tick, Ixodes scapularis, that was removed from a dog at Kenora, Ontario. This is the first time that B. burgdorferi spirochetes have been isolated from a black-legged tick on mainland Ontario.