Three diseases carried by ticks, and how to stay safe

Move over black flies. Growing tick populations and the diseases they carry are turning these critters into public enemy number one for those who love to be in the outdoors.

“Tick ranges are expanding with the increase in favourable climatic conditions, including warmer temperatures, that permit tick survival and the establishment of reproducing tick populations in more regions,” says Roman McKay, Project Manager for UPTick Research Project, a three-year study examining how urban changes affect human risk for tick-borne diseases from the University of Ottawa.

“Warming temperatures can also extend tick’s active season, allowing them to reproduce and colonize more rapidly.”

Three medical conditions carried by ticks

Cottagers should be aware that there are a number of diseases carried by ticks. Here are three on the radars of researchers:

1. Lyme disease

Lyme disease is caused by the bacterium Borellia burgdorferi. This bacteria is spread to humans through the bites of ticks from the genus Ixodes; in eastern North American the host tick is mainly Ixodes scapularis, better known as the blacklegged tick. In western North America the bacterium is commonly spread by Ixodes pacificus, or the western blacklegged tick.

“The most well-known early sign of Lyme disease infection is a ‘bulls-eye’ or erythema migraines rash, which occurs in approximately seventy percent of infected people,” writes McKay. “It begins at the site of a tick bite in about seven days, and then expands gradually over several days reaching up to thirty centimetres or more across.”

2. Babesiosis

Babesiosis is an infectious disease that affects red blood cells. It is caused by a single-celled parasites called Babesia. Like the bacterium that cause Lyme disease, Babesia parasites can be spread through the bite of infected Ixodes ticks, including Ixodes scapularis, otherwise known as the black-legged tick.

Babesiosis symptoms generally start one to eight weeks following contact with the parasite. Patients may or may not show signs of infection, but symptoms to watch out for include body aches, chills, fatigue, and fever.

Babesiosis is diagnosed through laboratory testing. Because the infection is caused by a parasite, treatment commonly requires use of both anti-parasitic drugs and antibiotics.

What blacklegged ticks look like, and where they’ve been seen:

Where has the black-legged tick been reported? 


3. Alpha-gal syndrome (AGS)

Alpha-gal syndrome is a food allergy to red meat. There is mounting evidence that AGS can be triggered by the bite of Amblyomma americanum, or the lone star tick.

Symptoms of alpha-gal syndrome occur after ingestion of red meat, and it’s worth noting that dairy and gelatin products can also provoke a reaction. A range of allergic responses can occur, from hives and facial swelling, to stomach upset and vomiting, to life-threatening anaphylaxis. Symptoms of anaphylaxis, including having difficulty breathing, indicate that emergency medical treatment is required.


What lone star ticks look like, and where they’ve been seen:


Click here to link to the up-to-date observation map for the lone star tick on

How to stay safe

With more ticks on the move, cottagers and other outdoor enthusiasts should take extra precautions to stay safe. McKay says that people can prevent tick bites by covering up when outdoors: wear long pants and shirts and shoes with socks. Use approved insect repellents that contain DEET or icaridin to keep ticks at bay, and always do a full body ‘tick check’ on yourself, children, and pets when coming in from the outdoors.

McKay adds that there are simple landscaping people can use to reduce tick populations around their properties, such as keeping grass mowed short. He also recommends that homeowners focus on the edges of their properties by removing brush and fallen leaves, and even creating a one-metre barrier of wood chips or rock to separate lawns from surrounding woodland.

Get involved

Cottagers who want to report sightings of ticks are encouraged to do so using the eTick mobile app. It provides a public platform for image-based identification and population monitoring of ticks in Canada.

Note that the eTick map shows locations in Canada where ticks have been observed and submitted to the eTick platform. This is not a risk map for tick-borne illnesses but rather a map that displays where ticks have been observed by Canadians. The data points are aggregated but zooming in to specific areas will allow you to see where specifically ticks were found. You can also click on individual points to see the submission information such as the tick species and when it was observed. Note that a maximum of 20000 points can be loaded at once and we suggest using date, province and/or species filters to maximize the number of points loaded in an area of interest.

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