This figure shows locations where the risk from tick bites and Lyme disease is known to occur, and where risk of tick bites and Lyme disease is possible. Locations where ticks and Lyme disease risk are known are called ‘endemic areas’ (‘known’ endemic areas indicated by red triangles if ticks and Lyme disease risk have been confirmed over several years of field study or by the occurrence of multiple human cases, otherwise they are called ‘suspect’ endemic areas which are indicated by blue circles). Also shown are hatched areas where surveillance and research studies suggest areas where ticks and Lyme disease risk have begun to become established.
The known and suspect endemic areas, and the possible risk areas, are indicated in insets on the map as follows:
Inset 1 - Southern Manitoba and Western Ontario
There are six known or suspect endemic areas in Manitoba: an area of the west side of Lake of the Woods (known endemic), the area of the Pembina escarpment including Pembina Valley Provincial Park (known endemic), the region of St. Malo (suspect area), the Vita/Arbakka region including the Roseau river (suspect area), Beaudry Provincial Park and the Assiniboine River (suspect area), locations adjacent to the Agassiz and Sandilands provincial forests (suspect area). Possible risk areas include southern Manitoba along the border with the US from south of Brandon to Lake of the Woods, around Winnipeg, and in western Ontario close to Lake of the Woods.
Inset 2 - Southern Ontario
There are five known endemic areas shown: Pointe-Pelee National Park, Rondeau Provincial Park, Turkey Point Provincial Park, Long Point peninsula including Long Point Provincial Park and the National Wildlife area, and Wainfleet bog near Welland on the Niagara peninsula.
Inset 3 - Southeastern Ontario and Southern Quebec
Two known endemic areas in Ontario are Prince Edward Point and parts of the Thousand Islands National Park. There are five known endemic areas in Montérégie, in the south of Québec, although in two cases these locations are close together so at the scale of the map, three known endemic areas are shown. Possible risk areas are locations around Kingston in the Saint Lawrence valley that extend north east towards Ottawa, locations covering much of Montérégie, and parts of Estrie and Centre du Québec in the south of Québec.
Inset 4 - Maritime Provinces
Two known endemic areas in New Brunswick (Millidgeville area of Saint John and North Head, Grand Manan Island) as well as six known endemic areas in Nova Scotia (areas of Halifax Regional Municipality and areas of the counties of Lunenburg, Shelburne, Yarmouth, Pictou and Queens) are shown. Possible risk areas shown are locations adjacent to known endemic areas in Pictou and Lunenburg counties in Nova Scotia.
Inset 5 - Southern British Columbia
Known endemic areas include the southern mainland and Vancouver Island. Possible risk areas include much of Vancouver Island and the coast of British Columbia facing Vancouver Island, as well as river valleys across southern British Columbia.
This figure is a map showing areas predicted to be at risk for emergence of Lyme endemic areas in the near future as the tick that transmits Lyme disease becomes more widespread in south eastern Canada (including southern Ontario, Quebec, New Brunswick and Nova Scotia) and, by means of an inset map of Manitoba, central Canada. The map shows regions that are colour-coded according to the degree of predicted risk. An orange zone covering southeastern Manitoba, western Ontario, southern parts of Ontario, southern parts of Quebec, New Brunswick and Nova Scotia indicates the main extent of locations where Lyme endemic areas may emerge. Regions of particularly high risk (southern Ontario, southern Quebec and southern Nova Scotia) are shown in red while further north a zone depicted in green, extending from Manitoba through Ontario and Quebec to New Brunswick and Nova Scotia indicate where the risk of Lyme endemic areas emerging is possible but comparatively lower. A grey zone covering most of the northern part of the map indicates areas where in general the risk of Lyme endemic area emergence is predicted to be low and risk of Lyme disease is mostly restricted to that posed by ‘adventitious’ ticks dispersed by migratory birds from Lyme endemic areas in Canada and the USA. Even so, in some areas of the grey risk zone, local environmental conditions may be suitable for Lyme endemic areas to emerge.
In this figure the size and pattern of unfed adult blacklegged ticks and adult American dog (wood) ticks are compared using a photograph of the ticks superimposed on a 1cm section of a plastic ruler. The photograph shows that American dog ticks are larger than the blacklegged ticks (female American dog ticks being approximately 0.5 cm long while female blacklegged ticks are approximately 0.3 cm long) and that the back of the American dog ticks are ornately patterned, while the back of blacklegged ticks are not patterned.
This figure shows the relative size and shape of unfed life stages of the blacklegged tick by using a photograph of a larva, a nymph, and adult male and an adult female superimposed on a 10-cent coin.
This figure shows the size and colour of female blacklegged ticks in various stages of feeding by using a photograph of five female ticks superimposed on a plastic ruler and next to which a 10-cent coin has been placed. The photograph shows that unfed female ticks are a dark reddish brown colour, they become paler brown to yellow as they start to feed, then they become greyish as they continue to feed and are dark grey-brown when fully fed. As the ticks feed the abdomen of the tick enlarges so the tick increases size from approximately 0.3 cm when unfed to 0.6 cm when partially engorged. When fully fed the tick is approximately 1cm long and egg shaped.
This figure shows the size and colour of nymphs of the blacklegged tick in various stages of feeding by using a photograph of three nymphs superimposed on a plastic ruler and next to which a 10-cent coin has been placed. The photograph shows that unfed nymphal ticks are very small (0.15 cm long) and grey-brown in colour. As they engorge their abdomen enlarges and darkens until when fully fed the engorged nymph is approximately 0.3 cm long, almost black in colour and egg shaped.