Ontarians are fortunate to have an abundance of wilderness that provides us with ample opportunity to enjoy the outdoors. But one thing to keep in mind when outside – especially in areas that are forested or have tall grasses, weeds or many shrubs – is Lyme disease.
Lyme disease can be serious. It is spread to humans through the bite of an infected, blacklegged tick. And health officials are seeing an increase in the number of cases in the province.
“The number of confirmed cases of Lyme disease in Ontario has been rising since 2011,” says Dr. David Williams, Ontario’s Chief Medical Officer of Health. “This is partly due to an expansion of black-legged tick populations to new areas of the province, especially in wooded areas.”
In Renfrew County and District, the prevalence of black-legged ticks and Lyme disease is still very low but it has been increasing in recent years. Tick surveillance and Lyme testing activities across Renfrew County in the spring and fall of 2016 has resulted in the Arnprior area now being added to the Ontario Lyme risk map. This is a reflection of the on-going northward migration of black-legged ticks and Lyme disease. The Health Unit will continue tick surveillance activities in 2017.
The Health Unit also accepts ticks that have been attached to humans for identification and Lyme testing.
Blacklegged ticks cannot fly, but settle on grass and bushes until they attach themselves to a bypassing person or animal. The ticks are known to feed on migratory birds and can be carried throughout the province.
A person can become infected with Lyme disease if they are bitten by an infected tick. Dr. Williams says in most cases, the tick must usually be attached for at least 24 hours for the Lyme disease bacterium to be passed on to the host.
The most commonly known symptom of Lyme disease is an expanding bulls-eye skin rash. The rash can begin at the site of the tick bite between three and 30 days after exposure and usually grows in size for several days. Many people never get or see a rash.
If the disease is left untreated, other symptoms may develop in the weeks following exposure, including rash, fever, chills, headache, fatigue, muscle and joint aches, problems with your heartbeat, breathing, balance and short-term memory. In rare cases Lyme disease may result in death.
“It is important to see your health care provider as early as possible if you have symptoms or if you feel unwell in the weeks following a tick bite,” says Dr. Williams. “The earlier treatment is received the better.”
Lyme disease is not transmitted from person-to-person. However, dogs and cats can carry the ticks into your home and place families at risk of being bitten. Check your pets for ticks daily and talk with your vet about keeping your pet protected from ticks. If your pet is found to have a tick, remember that you are at risk when spending time in the same outdoor environments.
Learn more about Lyme disease at www.ontario.ca/page/lyme-disease, and talk to your health care provider or local public health unit.
How to Fight the Bite
The most effective way to prevent Lyme disease is to prevent tick bites. Here are some tips to protect yourself and your family from tick bites:
• Wear light-coloured clothing. It makes ticks easier to spot.
• Wear closed footwear and socks, a long sleeved shirt tucked into long pants. Tuck your pants into your socks.
• Use a tick repellent that has DEET or Icaridin on clothes and exposed skin (be sure to follow the manufacturer’s directions).
• Search your clothes and body for ticks at least once a day, paying special attention to areas such as the groin, navel, armpits, scalp, and behind ears and knees. Use a mirror to check the back of your body or have someone else check for you. Don’t forget to tick check children in your care.
• Take a shower as soon as you can after being outdoors to more easily find and wash off any ticks crawling on you.
• Place outdoor clothing through the dryer cycle for 60 minutes on high heat before washing to kill any ticks that may be hard to see. Ticks thrive in wet environments.
Current Lyme disease risk areas in Ontario
While not all blacklegged ticks can cause Lyme disease, there has been an increase in the number of areas in Ontario where blacklegged ticks have been identified or are known to exist.
In Ontario, locations that have established blacklegged tick populations include areas in Eastern, Southwestern, Central and Northwestern Ontario.
While the probability is low, it’s possible to encounter an infected tick almost anywhere in the province. For more information, please contact the Health Unit at 613-735-8654 extension 555 or www.rcdhu.com.
