SHORT COMMUNICATION
Isolation of the Lyme Disease Spirochete, Borrelia burgdorferi, from Ixodes dammini (Acari: Ixodidae) Collected on Prince Edward Island, Canada HARVEY ARTSOB, MAXWELL GARVIE, RICK J. CAWTHORN,i BARBARA HORNEY,* ROBERT MALONEY, 1 DARYL DICK, AND SCOTT McBURNEY* National Laboratory for Special Pathogens, Bureau of Microbiology, Laboratory Centre for Disease Control, Tunney's Pasture, Ottawa, Ontario, Canada, K1A OL2
KEY WORDS Lyme disease, Ixodes dammini, Borrelia burgdorferi
LYME DISEASE was documented as caused by a tick-transmitted agent of bacterial etiology by studies conducted in the United States from 1975 to 1982 (Steere et al. 1986). By the end of 1990, Lyme disease had been reported from 46 states with the greatest number of cases from New York and states along the eastern seaboard (Cartter et al. 1991). Lyme disease has also been reported in Canada with provisional data as of June 1990, indicating that 103 cases have been identified from seven provinces (MacKenzie 1990). However, many of these reported cases were likely contracted outside the country. Despite these reported cases, the only currently documented area of activity of Borrelia burgdorferi, the etiologic agent of Lyme disease, in Canada is at Long Point in southern Ontario. At this location, numerous isolates of B. burgdorferi have been obtained from ticks and mice in studies conducted from 1987 to 1990 (Barker et al. 1992). Long Point is the only area in Canada where a major North American vector of B. burgdorferi, Ixodes dammini Spielman, Clifford, Piesman & Corwin, has been shown to be en1 Department of Pathology and Microbiology, Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island, Canada, CIA 4P3.
demic, although there are reports of this tick in several other provinces (Costero 1990). In 1989, three adult I. dammini were recovered from domestic pets on Prince Edward Island and four additional ticks were submitted to the Atlantic Veterinary College in 1990 (Cawthorn et al. 1990, Costero 1990). Therefore, in 1991 a study was initiated to examine livecollected ticks from Prince Edward Island for the presence of B. burgdorferi. In addition, a limited serological survey was undertaken on animal sera collected in Prince Edward Island from 1989 to February 1992. The results are presented in this report.
Materials and Methods The gut contents of each tick were removed by use of a 2.5-cc syringe and a 22-gauge needle. Each tick was surface sterilized by submersion in 95% ethanol followed by washing in sterile phosphate-buffered saline. The needle was then inserted above the anal groove. Each syringe contained 0.5 ml sterile BSKII medium, of which =0.1 ml was injected into the tick until it became fully distended. The medium was then removed along with the tick gut contents.
0022-2585/92/1063-1066$02.00/0 © 1992 Entomological Society of America
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
J. Med. Entomol. 29(6): 1063-1066 (1992) ABSTRACT Studies were undertaken to monitor for the presence of Borrelia burgdorferi, the etiologic agent of Lyme disease, on Prince Edward Island, Canada. Gut contents were removed for culturing from seven engorged ticks collected in 1991-1992 including five Ixodes dammini (Spielman, Clifford, Piesman & Corwin) and two /. scapularis (Say) removed from a dog that had recently traveled to the southern United States. B. burgdorferi was recovered from one I. dammini that had been removed from a cat in Charlottetown in October 1991. The cat had not traveled off the island. Immunofluorescent antibody (IFA) studies on sera from 75 dogs, 7 cats, and 8 white-tailed deer (Odocoileus virginianus) collected on Prince Edward Island between 1989 and 1992 revealed one reactor with an IFA titer sl:256. The reactor was a dog with a history of travel to the United States. This report documents the first isolate of B. burgdorferi in Atlantic Canada, possibly because of the introduction of I. dammini on migratory birds. Serological studies do not indicate widespread occurrence of B. burgdorferi on Prince Edward Island.
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Table 1. Ticks from Prince Edward Island examined for the possible presence of B. burgdorferi Collection date T26 T27 T28 T29 T30 T31 T32
October 1991 October 1991 November 1991 November 1991 November 1991 January 1992 January 1992
Species" of Ixodes I. I. I. 1. I. I. I.
dammini damminib dammini dammini dammini scapularisc scapularisc
Tick Source
Collection location
Cat Cat Cat Dog Backpack Dog Dog
Prince County Charlottetown Charlottetown Montague Iona Charlottetown Charlottetown
" All ticks examined were engorged adult females. b B. burgdorferi was isolated from this tick only. ° Removed from a dog that had recently returned from a trip to the southern United States.
Results Seven live, engorged ticks were received for examination between October 1991 and January
1992 (Table 1). All were adult females, of which three were removed from cats, three from dogs, and one from a person's backpack. After removal of gut contents, the ticks were placed in 70% alcohol and submitted to Dr. Evert Lindquist (Center for Land and Biological Resources Research, Ottawa) for species determination. Five of the ticks (accession numbers BRC 91-571, 91636, 91-705, 91-706, 91-707) were /. dammini, whereas the remaining two ticks (accession number BRC 92-36) were identified as 7. scapularis (Say). The two /. scapularis were removed from a dog that had recently traveled to areas in the southern United States where this tick is endemic. Thus, it is likely that the tick was brought back to Prince Edward Island on the dog. No histories of recent travel were elicited for any of the pets from which /. dammini were removed. Darkfield microscopy of gut contents from one female /. dammini (T27) removed from a cat in Charlottetown revealed the presence of numerous spirochetes. Viable organisms were seen after 1 d in both tubes of medium inoculated with gut contents of T27. By 2 wk after inoculation, the BSKII medium inoculated with T27 had a pure culture containing moderate growth of a spirochete isolate designated as T27-91. By contrast, the spirochetes in the selective medium containing antibiotics were all nonviable. Antigen was prepared from isolate T27-91 and reacted by IFA with two murine monoclonal antibodies supplied by Dr. Alan Barbour (University of Texas Health Science Center, San Antonio). Isolate T27-91 reacted both with monoclone H9724, which is reactive with all Borrelia species, and monoclone H5332, which reacts specifically with the outer surface protein A of B. burgdorferi (Barbour et al. 1983). Thus, isolate T27-91 was identified as B. burgdorferi. Six of the 90 sera from Prince Edward Island animals were reactive by IFA, including sera from five dogs and one deer (Table 2). However, serum titers of three dogs and the deer were 1:128 were further tested using a CITE ELISA test manufactured by Idexx (Portland, ME). The ELISA test was undertaken according to instructions on the package insert.
Vol. 29, no. 6
November 1992
ARTSOB ET AL.: LYME DISEASE ON PRINCE EDWARD ISLAND, CANADA
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Table 2. Sera from Prince Edward Island mammals tested for antibodies to B. burgdorferi Animal
Collection dates
No. sera tested
Reactors"
Titer
Location
1:32 1:64 1:64 l:128 b 1:2563 — 1:32
Charlottetown Summerside Summerside Rocky Point Travel to Connecticut Several P.E.I, locations Eastern P.E.I.
Dog, random serosurvey
May-June 1989
61
4
Dog, diagnostic submissions Cat Deer
August 1989-February 1992 June 1989-February 1992 September 1990
14 7 8
1 0 1
° Number of sera with immunofluorescent antibody titers sl:32. Nonreactive by CITE ELISA, a commercial ELISA kit manufactured by Idexx, Portland, ME. c Reactive to high titer by CITE ELISA. b
58 birds of which 56 ticks (22%) were infected with B. burgdorferi. I. dammini, including the specimen that yielded isolate T27-91, may be introduced to Atlantic Canada by migrating birds from Lyme endemic areas on the eastern seaboard of the United States. Once introduced, the larvae or nymphs may develop into adults. The major host for adult 7. dammini, the white-tailed deer, is found in Nova Scotia and New Brunswick but does not occur naturally on Prince Edward Island. The possible existence of alternative hosts for adult 7. dammini on Prince Edward Island is currently being explored. Despite this isolation of B. burgdorferi, limited serological studies undertaken on animals from Prince Edward Island do not indicate that infection with B. burgdorferi is widespread. Similarly, Bell et al. (1992) found no evidence for B. burgdorferi activity in Nova Scotia either by culturing from 650 American dog ticks, Dermacentor variabilis (Say), or by a serosurvey of 137 dogs. Nevertheless, this isolation does underscore the potential for locally acquired cases of Lyme disease to occur in Atlantic Canada. Acknowledgments We thank John Anderson (Connecticut Agricultural Research Station, New Haven), who kindly supplied Borrelia burgdorferi antibody-positive cat and dog sera; Evert Lindquist (Biological Resources Division, Centre for Land and Biological Resources Research, Agriculture Canada, Ottawa), who confirmed all tick identifications; and the local veterinarians who submitted ticks from infested pets. References Cited Anderson, J. F. 1988. Mammalian and avian reservoirs for Borrelia burgdorferi. Ann. N.Y. Acad. Sci. 539: 180-191. Anonymous. 1991. Consensus conference on Lyme disease. Can. J. Infect. Dis. 2: 49-70. Barbour, A. G. 1984. Isolation and cultivation of Lyme disease spirochetes. Yale J. Biol. Med. 57: 521-526. Barbour, A. G., S. L. Tessier & W. Todd. 1983. Lyme disease spirochetes and ixodid tick spiro-
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
Discussion Ixodes dammini occurs in Atlantic Canada, at least on a seasonal basis, but evidence that the tick is endemic in this region is currently lacking. Current studies include flagging and examination of small mammals in Nova Scotia (Bell et al. 1992) and passive surveillance for /. dammini in Prince Edward Island and New Brunswick (R. J. Cawthorn & R. Maloney, unpublished data). Evidence for I. dammini endemicity would require the demonstration of all three stages (larva, nymph, and adult) in a locality on resident animals or in the environment for at least 2 consecutive yr (Anonymous 1991). To date, I. dammini collections from Atlantic Canada have been almost exclusively adults with the exception of one nymph taken from a yellow throat, Geothypis trichas, in Nova Scotia in May 1990 (Bell et al. 1992). More recently, however, a gravid female /. dammini was removed from a cat in Cape Breton, Nova Scotia, and, under laboratory conditions, produced eggs which subsequently hatched into larvae (C. R. Bell, personal communication). Collections of 7. dammini have included 20 adults recovered on Prince Edward Island, including one removed from a boy in Summerside in 1988 (Bollegraaf 1988) and 19 obtained between 1989 and 1991 primarily from domestic pets (Cawthorn et al. 1990, Costero 1990, R. J. Cawthorn & R. Maloney, unpublished data). All of these ticks were obtained by passive surveillance, and it is difficult to estimate how many ticks were missed. Other reports of/, dammini in Atlantic Canada include 24 adults and 1 nymph from Nova Scotia (Bell et al. 1992; C. R. Bell, personal communication) and four adults from New Brunswick (Costero 1990; R. J. Cawthorn & R. Maloney, unpublished data). It is feasible that 7. dammini is repeatedly introduced into Atlantic Canada by birds. In the United States, larval and nymphal (but not adult) 7. dammini have been recovered from 49 species of ground-inhabiting birds belonging to 17 families (Anderson 1988). Weisbrod & Johnson (1989) studied migrating birds in the Saint Croix River Valley and found 250 deer ticks infesting
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Costero, A. 1990. Identification of the Lyme disease vector in Canada. Can. Dis. Weekly Rep. 16: 142— 147. Johnson, S. E., G. C. Klein, G. P. Schmid, G. S. Bowen, J. C. Feeley & T. Schulze. 1984. Lyme disease: a selective medium for isolation of the suspected etiological agent, a spirochete. J. Clin. Microbiol. 19: 81-82. MacKenzie, S. G. 1990. Update—Lyme disease in Canada. Can. Dis. Weekly Rep. 16: 141-142. Steere, A. C , D. Snydman, P. Murray, J. Mensch, A. J. Main, R. C. VVallis, R. E. Shope & S. E. Malawista. 1986. Historical perspectives of Lyme disease. Zentrlbl. Bakteriol. Mikrobiol. Hyg. Ser. A 263: 3-6. Weisbrod, A. R. & R. C. Johnson. 1989. Lyme disease and migrating birds in the Saint Croix River Valley. Appl. Environ. Microbiol. 55: 1921-1924. Wilkinson, H. W. 1984. Immunodiagnostic tests for Lyme disease. Yale J. Biol. Med. 57: 567-572. Received for publication 15 April 1992; accepted 7 July 1992.
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
chetes share a common surface antigenic determinant defined by monoclonal antibody. Infect. Immun. 41: 795-804. Barker, I. K., C. A. Surgeoner, H. Artsob, S. A. McEwen, L. Elliott, G. D. Campbell & J. T. Robinson. Distribution of the Lyme disease vector, Ixodes dammini (Acari: Ixodidae), and isolation of Borrelia burgdorferi in Ontario, Canada. J. Med. Entomol. (in press). Bell, C. R., H. B. Specht & B. A. Coombs. The search for Ixodes dammini and Borrelia burgdorferi in Nova Scotia. Can. J. Infect. Dis. (in press). Bollegraaf, E. 1988. Lyme disease in Canada. Can. Dis. Weekly Rep. 14: 95-97. Cartter, M. L., J. L. Hadler, J. D. Smith, J. A. Wilber, M. G. Stobierski, K. R. Wilcox, H. D. Donnell, C. Genese, K. C. Spitainy, J. J. Kazmierczak & J. P. Davis. 1991. Lyme disease surveillance— United States, 1989-1990. M.M.W.R. 40: 417-421. Cawthorn, R. J., B. S. Horney & R. Maloney. 1990. Lyme disease vector, Ixodes dammini (the northern deer tick), identified in Prince Edward Island. Can. Vet. J. 31: 220.
Vol. 29, no. 6
Isolation of the Lyme Disease Spirochete, Borrelia burgdorferi, from Ixodes dammini (Acari: Ixodidae) Collected on Prince Edward Island, Canada HARVEY ARTSOB, MAXWELL GARVIE, RICK J. CAWTHORN,i BARBARA HORNEY,* ROBERT MALONEY, 1 DARYL DICK, AND SCOTT McBURNEY* National Laboratory for Special Pathogens, Bureau of Microbiology, Laboratory Centre for Disease Control, Tunney's Pasture, Ottawa, Ontario, Canada, K1A OL2
KEY WORDS Lyme disease, Ixodes dammini, Borrelia burgdorferi
LYME DISEASE was documented as caused by a tick-transmitted agent of bacterial etiology by studies conducted in the United States from 1975 to 1982 (Steere et al. 1986). By the end of 1990, Lyme disease had been reported from 46 states with the greatest number of cases from New York and states along the eastern seaboard (Cartter et al. 1991). Lyme disease has also been reported in Canada with provisional data as of June 1990, indicating that 103 cases have been identified from seven provinces (MacKenzie 1990). However, many of these reported cases were likely contracted outside the country. Despite these reported cases, the only currently documented area of activity of Borrelia burgdorferi, the etiologic agent of Lyme disease, in Canada is at Long Point in southern Ontario. At this location, numerous isolates of B. burgdorferi have been obtained from ticks and mice in studies conducted from 1987 to 1990 (Barker et al. 1992). Long Point is the only area in Canada where a major North American vector of B. burgdorferi, Ixodes dammini Spielman, Clifford, Piesman & Corwin, has been shown to be en1 Department of Pathology and Microbiology, Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island, Canada, CIA 4P3.
demic, although there are reports of this tick in several other provinces (Costero 1990). In 1989, three adult I. dammini were recovered from domestic pets on Prince Edward Island and four additional ticks were submitted to the Atlantic Veterinary College in 1990 (Cawthorn et al. 1990, Costero 1990). Therefore, in 1991 a study was initiated to examine livecollected ticks from Prince Edward Island for the presence of B. burgdorferi. In addition, a limited serological survey was undertaken on animal sera collected in Prince Edward Island from 1989 to February 1992. The results are presented in this report.
Materials and Methods The gut contents of each tick were removed by use of a 2.5-cc syringe and a 22-gauge needle. Each tick was surface sterilized by submersion in 95% ethanol followed by washing in sterile phosphate-buffered saline. The needle was then inserted above the anal groove. Each syringe contained 0.5 ml sterile BSKII medium, of which =0.1 ml was injected into the tick until it became fully distended. The medium was then removed along with the tick gut contents.
0022-2585/92/1063-1066$02.00/0 © 1992 Entomological Society of America
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
J. Med. Entomol. 29(6): 1063-1066 (1992) ABSTRACT Studies were undertaken to monitor for the presence of Borrelia burgdorferi, the etiologic agent of Lyme disease, on Prince Edward Island, Canada. Gut contents were removed for culturing from seven engorged ticks collected in 1991-1992 including five Ixodes dammini (Spielman, Clifford, Piesman & Corwin) and two /. scapularis (Say) removed from a dog that had recently traveled to the southern United States. B. burgdorferi was recovered from one I. dammini that had been removed from a cat in Charlottetown in October 1991. The cat had not traveled off the island. Immunofluorescent antibody (IFA) studies on sera from 75 dogs, 7 cats, and 8 white-tailed deer (Odocoileus virginianus) collected on Prince Edward Island between 1989 and 1992 revealed one reactor with an IFA titer sl:256. The reactor was a dog with a history of travel to the United States. This report documents the first isolate of B. burgdorferi in Atlantic Canada, possibly because of the introduction of I. dammini on migratory birds. Serological studies do not indicate widespread occurrence of B. burgdorferi on Prince Edward Island.
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JOURNAL OF MEDICAL ENTOMOLOGY
Table 1. Ticks from Prince Edward Island examined for the possible presence of B. burgdorferi Collection date T26 T27 T28 T29 T30 T31 T32
October 1991 October 1991 November 1991 November 1991 November 1991 January 1992 January 1992
Species" of Ixodes I. I. I. 1. I. I. I.
dammini damminib dammini dammini dammini scapularisc scapularisc
Tick Source
Collection location
Cat Cat Cat Dog Backpack Dog Dog
Prince County Charlottetown Charlottetown Montague Iona Charlottetown Charlottetown
" All ticks examined were engorged adult females. b B. burgdorferi was isolated from this tick only. ° Removed from a dog that had recently returned from a trip to the southern United States.
Results Seven live, engorged ticks were received for examination between October 1991 and January
1992 (Table 1). All were adult females, of which three were removed from cats, three from dogs, and one from a person's backpack. After removal of gut contents, the ticks were placed in 70% alcohol and submitted to Dr. Evert Lindquist (Center for Land and Biological Resources Research, Ottawa) for species determination. Five of the ticks (accession numbers BRC 91-571, 91636, 91-705, 91-706, 91-707) were /. dammini, whereas the remaining two ticks (accession number BRC 92-36) were identified as 7. scapularis (Say). The two /. scapularis were removed from a dog that had recently traveled to areas in the southern United States where this tick is endemic. Thus, it is likely that the tick was brought back to Prince Edward Island on the dog. No histories of recent travel were elicited for any of the pets from which /. dammini were removed. Darkfield microscopy of gut contents from one female /. dammini (T27) removed from a cat in Charlottetown revealed the presence of numerous spirochetes. Viable organisms were seen after 1 d in both tubes of medium inoculated with gut contents of T27. By 2 wk after inoculation, the BSKII medium inoculated with T27 had a pure culture containing moderate growth of a spirochete isolate designated as T27-91. By contrast, the spirochetes in the selective medium containing antibiotics were all nonviable. Antigen was prepared from isolate T27-91 and reacted by IFA with two murine monoclonal antibodies supplied by Dr. Alan Barbour (University of Texas Health Science Center, San Antonio). Isolate T27-91 reacted both with monoclone H9724, which is reactive with all Borrelia species, and monoclone H5332, which reacts specifically with the outer surface protein A of B. burgdorferi (Barbour et al. 1983). Thus, isolate T27-91 was identified as B. burgdorferi. Six of the 90 sera from Prince Edward Island animals were reactive by IFA, including sera from five dogs and one deer (Table 2). However, serum titers of three dogs and the deer were 1:128 were further tested using a CITE ELISA test manufactured by Idexx (Portland, ME). The ELISA test was undertaken according to instructions on the package insert.
Vol. 29, no. 6
November 1992
ARTSOB ET AL.: LYME DISEASE ON PRINCE EDWARD ISLAND, CANADA
1065
Table 2. Sera from Prince Edward Island mammals tested for antibodies to B. burgdorferi Animal
Collection dates
No. sera tested
Reactors"
Titer
Location
1:32 1:64 1:64 l:128 b 1:2563 — 1:32
Charlottetown Summerside Summerside Rocky Point Travel to Connecticut Several P.E.I, locations Eastern P.E.I.
Dog, random serosurvey
May-June 1989
61
4
Dog, diagnostic submissions Cat Deer
August 1989-February 1992 June 1989-February 1992 September 1990
14 7 8
1 0 1
° Number of sera with immunofluorescent antibody titers sl:32. Nonreactive by CITE ELISA, a commercial ELISA kit manufactured by Idexx, Portland, ME. c Reactive to high titer by CITE ELISA. b
58 birds of which 56 ticks (22%) were infected with B. burgdorferi. I. dammini, including the specimen that yielded isolate T27-91, may be introduced to Atlantic Canada by migrating birds from Lyme endemic areas on the eastern seaboard of the United States. Once introduced, the larvae or nymphs may develop into adults. The major host for adult 7. dammini, the white-tailed deer, is found in Nova Scotia and New Brunswick but does not occur naturally on Prince Edward Island. The possible existence of alternative hosts for adult 7. dammini on Prince Edward Island is currently being explored. Despite this isolation of B. burgdorferi, limited serological studies undertaken on animals from Prince Edward Island do not indicate that infection with B. burgdorferi is widespread. Similarly, Bell et al. (1992) found no evidence for B. burgdorferi activity in Nova Scotia either by culturing from 650 American dog ticks, Dermacentor variabilis (Say), or by a serosurvey of 137 dogs. Nevertheless, this isolation does underscore the potential for locally acquired cases of Lyme disease to occur in Atlantic Canada. Acknowledgments We thank John Anderson (Connecticut Agricultural Research Station, New Haven), who kindly supplied Borrelia burgdorferi antibody-positive cat and dog sera; Evert Lindquist (Biological Resources Division, Centre for Land and Biological Resources Research, Agriculture Canada, Ottawa), who confirmed all tick identifications; and the local veterinarians who submitted ticks from infested pets. References Cited Anderson, J. F. 1988. Mammalian and avian reservoirs for Borrelia burgdorferi. Ann. N.Y. Acad. Sci. 539: 180-191. Anonymous. 1991. Consensus conference on Lyme disease. Can. J. Infect. Dis. 2: 49-70. Barbour, A. G. 1984. Isolation and cultivation of Lyme disease spirochetes. Yale J. Biol. Med. 57: 521-526. Barbour, A. G., S. L. Tessier & W. Todd. 1983. Lyme disease spirochetes and ixodid tick spiro-
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
Discussion Ixodes dammini occurs in Atlantic Canada, at least on a seasonal basis, but evidence that the tick is endemic in this region is currently lacking. Current studies include flagging and examination of small mammals in Nova Scotia (Bell et al. 1992) and passive surveillance for /. dammini in Prince Edward Island and New Brunswick (R. J. Cawthorn & R. Maloney, unpublished data). Evidence for I. dammini endemicity would require the demonstration of all three stages (larva, nymph, and adult) in a locality on resident animals or in the environment for at least 2 consecutive yr (Anonymous 1991). To date, I. dammini collections from Atlantic Canada have been almost exclusively adults with the exception of one nymph taken from a yellow throat, Geothypis trichas, in Nova Scotia in May 1990 (Bell et al. 1992). More recently, however, a gravid female /. dammini was removed from a cat in Cape Breton, Nova Scotia, and, under laboratory conditions, produced eggs which subsequently hatched into larvae (C. R. Bell, personal communication). Collections of 7. dammini have included 20 adults recovered on Prince Edward Island, including one removed from a boy in Summerside in 1988 (Bollegraaf 1988) and 19 obtained between 1989 and 1991 primarily from domestic pets (Cawthorn et al. 1990, Costero 1990, R. J. Cawthorn & R. Maloney, unpublished data). All of these ticks were obtained by passive surveillance, and it is difficult to estimate how many ticks were missed. Other reports of/, dammini in Atlantic Canada include 24 adults and 1 nymph from Nova Scotia (Bell et al. 1992; C. R. Bell, personal communication) and four adults from New Brunswick (Costero 1990; R. J. Cawthorn & R. Maloney, unpublished data). It is feasible that 7. dammini is repeatedly introduced into Atlantic Canada by birds. In the United States, larval and nymphal (but not adult) 7. dammini have been recovered from 49 species of ground-inhabiting birds belonging to 17 families (Anderson 1988). Weisbrod & Johnson (1989) studied migrating birds in the Saint Croix River Valley and found 250 deer ticks infesting
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JOURNAL OF MEDICAL ENTOMOLOGY
Costero, A. 1990. Identification of the Lyme disease vector in Canada. Can. Dis. Weekly Rep. 16: 142— 147. Johnson, S. E., G. C. Klein, G. P. Schmid, G. S. Bowen, J. C. Feeley & T. Schulze. 1984. Lyme disease: a selective medium for isolation of the suspected etiological agent, a spirochete. J. Clin. Microbiol. 19: 81-82. MacKenzie, S. G. 1990. Update—Lyme disease in Canada. Can. Dis. Weekly Rep. 16: 141-142. Steere, A. C , D. Snydman, P. Murray, J. Mensch, A. J. Main, R. C. VVallis, R. E. Shope & S. E. Malawista. 1986. Historical perspectives of Lyme disease. Zentrlbl. Bakteriol. Mikrobiol. Hyg. Ser. A 263: 3-6. Weisbrod, A. R. & R. C. Johnson. 1989. Lyme disease and migrating birds in the Saint Croix River Valley. Appl. Environ. Microbiol. 55: 1921-1924. Wilkinson, H. W. 1984. Immunodiagnostic tests for Lyme disease. Yale J. Biol. Med. 57: 567-572. Received for publication 15 April 1992; accepted 7 July 1992.
Downloaded from http://jme.oxfordjournals.org/ by guest on June 6, 2016
chetes share a common surface antigenic determinant defined by monoclonal antibody. Infect. Immun. 41: 795-804. Barker, I. K., C. A. Surgeoner, H. Artsob, S. A. McEwen, L. Elliott, G. D. Campbell & J. T. Robinson. Distribution of the Lyme disease vector, Ixodes dammini (Acari: Ixodidae), and isolation of Borrelia burgdorferi in Ontario, Canada. J. Med. Entomol. (in press). Bell, C. R., H. B. Specht & B. A. Coombs. The search for Ixodes dammini and Borrelia burgdorferi in Nova Scotia. Can. J. Infect. Dis. (in press). Bollegraaf, E. 1988. Lyme disease in Canada. Can. Dis. Weekly Rep. 14: 95-97. Cartter, M. L., J. L. Hadler, J. D. Smith, J. A. Wilber, M. G. Stobierski, K. R. Wilcox, H. D. Donnell, C. Genese, K. C. Spitainy, J. J. Kazmierczak & J. P. Davis. 1991. Lyme disease surveillance— United States, 1989-1990. M.M.W.R. 40: 417-421. Cawthorn, R. J., B. S. Horney & R. Maloney. 1990. Lyme disease vector, Ixodes dammini (the northern deer tick), identified in Prince Edward Island. Can. Vet. J. 31: 220.
Vol. 29, no. 6
