Health, Seniors and Active Living
Blacklegged Tick Risk Areas in Manitoba
In Manitoba, the range of blacklegged ticks continues to expand. Despite this expansion not all areas in southern Manitoba provide suitable habitats for blacklegged ticks. Consequently blacklegged ticks are most commonly found:
- within and along the edges of wooded or forested habitat and in areas,
- with thick, woody shrubs and other vegetation that provide sufficient cover and typically high humidity.
Blacklegged ticks are more likely to be found within identified Blacklegged Tick Risk Areas than in other parts of the province. These blacklegged ticks are also more likely to carry the agents that cause tick-borne diseases like Anaplasmosis, Babesiosis and Lyme Disease than blacklegged ticks found in other parts of the province. Known Blacklegged Tick Risk Areas are identified in the map below. It should be noted that the distribution of blacklegged ticks within these risk areas is not uniform. For example, forested habitats, even small plots within farmland, dominated by trees that shed their leaves on an annual basis, can provide ideal habitat for both blacklegged ticks and the animals (e.g. small rodents, birds and deer) that they normally feed on. Blacklegged ticks are much less likely to be found in open grasslands, agricultural land, bogs or wetlands and in areas that are very dry as these conditions are much less suitable for tick survival.
It is possible to find blacklegged ticks in areas outside the known Blacklegged Tick Risk Areas of Manitoba because ticks can attach to migrating birds and be carried over large distances. However, the disease risk is relatively low because the chance of encountering infected blacklegged ticks is less likely outside of these risk areas. Manitoba Health, Seniors and Active Living (MHSAL) and its partners continue to monitor and define the boundaries of Blacklegged Tick Risk Areas as the range of these ticks is expected to expand over time.
What does the map show?
The areas shaded in orange on the map are Blacklegged Tick Risk Areas, where established blacklegged tick populations have been found and the risk of acquiring tick-borne diseases (i.e. Anaplasmosis, Babesiosis and Lyme disease) is higher.
The small grey circles on the map show places where blacklegged ticks were submitted as part of the passive tick surveillance program over several years. These grey circles do not represent the number of blacklegged ticks submitted from a particular place, though typically only small numbers of ticks are submitted. Risk of exposure to infected blacklegged ticks in these areas is typically much lower than in areas where tick populations are established.
Communities and other markings in black have been added to help provide scale and orientation to the map.
What is MHSAL doing to find blacklegged ticks?
Passive tick surveillance has been ongoing in Manitoba since 1995. Ticks found by veterinarians, doctors and the general public are submitted to Cadham Provincial Laboratory for identification. Blacklegged ticks are then sent to the National Microbiology Laboratory where they are tested for a number of causative agents of tick-borne diseases of public health importance.
- Click here for the new Manitoba Tick Checker
MHSAL uses the information about where blacklegged ticks are found, along with other information, to decide when and where to send staff out into the field to look for blacklegged ticks. This is called active surveillance and it takes place every year. MHSAL adjusts the Blacklegged Tick Risk Areas based on the results of active surveillance.
Distribution of Blacklegged Tick Risk Areas in Manitoba
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