Distribution of the Lyme Disease Vector, Ixodes dammini (Acari: Ixodidae) and Isolation of Borrelia burgdorferi in Ontario, Canada

Abstract

Ixodes dammini Spielman, Clifford, Piesman & Corwin was confirmed at Long Point, Lake Erie, Ontario, on small mammals and white-tailed deer and by dragging for ticks. Mean intensities of up to 16.2 larvae and 2.1 nymphs were found on Peromyscus leucopus (Rafinesque), with an overall prevalence of infestation up to 92%. Adult I. dammini (101.6 +/- 77.63) (mean +/- SD) were found on 8 white-tailed deer, Odocoileus virginianus (Zimmerman). The seasonal pattern of recovery of ticks from hosts and the environment resembled that described elsewhere. I. dammini was not found on 952 small mammals trapped at 25 other localities throughout Ontario, although other ticks (Derma-centor variabilis (Packard), Ixodes angustus Neumann, I. marxi Banks, I. muris Bishopp & Smith) were encountered sporadically. I. dammini is not widespread or common in Ontario other than at Long Point. Borrelia burgdorferi was isolated from 10 of 151 P. leucopus; from larval and nymphal I. dammini; and from nymphal and adult D. variabilis, all from Long Point. B. burgdorferi was not recovered from 116 small mammals from localities other than Long Point. Seropositive P. leucopus (indirect fluorescent antibody test titer > or = 1:20) were common (up to 30% prevalence in July 1988, n = 23) on Long Point. Where I. dammini was not found, the prevalence of seroreactors among Peromyscus was 0 (15 sites), < 12% (5 sites), and 29% (1 site); seroprevalence at 1:20 could not be calculated for a further 4 sites examined in 1987. Antibody to B. burgdorferi was also detected in other small mammals at some sites. Such antibody was interpreted as possibly cross-reacting or caused by direct transmission.

The Biological Survey of Canada: A Personal History

“…Although there are many records for this mouse tick in eastern Canada, there have been no detailed studies into its natural history in this region (e.g., Barker et al 1992). The most complete examination of its natural history was conducted in Massachusetts (Smith 1944), from which the following has been summarised.…”

“…The large range and apparent lack of host specificity have resulted in this tick being reported frequently in the literature from many host species, mostly rodents and insectivores (e.g., Bishopp and Trembley 1945;Judd 1950;Gregson 1956;Martell et al 1969;Whitaker and French 1982;Barker et al 1992;Durden and Keirans 1996;Nieto et al 2007;Anstead et al 2013). Despite being regularly encountered, it is seldom collected in large numbers, and there are limited data from field studies on its natural history.…”

“…There are a number of records for I. marxi in eastern Canada (McLean and Larke 1963;Jones and Thomas 1980;Gyorkos and Hilton 1982;Barker et al 1992), where it primarily parasitises tree squirrels. These records have mostly been anecdotal in nature, and there is little information on the natural history of this species.…”

The emergence of Lyme disease in Canada

“…In the early 1990s, only 1 geographically discrete population of I. scapularis was known, at Long Point on the Ontario shore of Lake Erie. 11 Since 1997, detection of human cases by vigilant clinicians and passive surveillance for ticks 12 has led to the identification of populations of I. scapularis in southern Ontario, Nova Scotia, southeastern Manitoba and New Brunswick (Figure 2). 13 In addition, active surveillance driven by risk maps (Box 1) has identified the possibility of additional emerging populations in southern Quebec, in the absence of a clear signal from passive surveillance.…”

A framework for incorporating the prevention of Lyme disease transmission into the landscape planning and design process

“…In eastern North America, the tick vector is the black-legged tick (Ixodes scapularis formerly Ixodes dammini), the range of which is expanding (Anderson et al, 1990;Barker et al, 1992).…”