Mosquitoes, ticks, and bed bugs
Diseases that are spread to humans and other animals by an insect or tick is called a vector-borne disease.
Mosquitoes and West Nile Virus
West Nile Virus is a potentially serious illness that is spread to people through the bite of an infected mosquito. Symptoms, severity, and duration can vary from person to person. Protect yourself by preventing mosquito bites. Avoid areas with many mosquitos, cover exposed skin, use an insect repellent when appropriate and remove stagnant water on your property.
Learn more from Health Canada about symptoms, treatment, and prevention of West Nile Virus.
Extreme rainfall can cause stagnant water on properties, which can cause mosquitos to breed.
Drain or dry off water that has accumulated on areas of your property like:
- old tires
- rainwater barrels
- children’s toys and wading pools
- flowerpots and wheelbarrows
- pools covers and tarps
Report stagnant water
Stagnant water is water that collects and stays for 7 days or longer. Stagnant water is ideal for mosquitoes to breed especially from mid-May to the end of August. Report stagnant water.
Larviciding is one measure used to reduce mosquito breeding. It involves the use of environmentally friendly products to control mosquito larvae, which are an immature form of mosquitoes that live in water. There are strict regulations by the Ministry of Environment, Conservation and Parks on the use of larvicides. Larvicides can only be applied by trained and licensed applicators, who must obtain a permit from the Ministry of Environment, Conservation and Parks.
What we do in Peel
Larvicides are applied to standing water as granules, pellets or briquets. They are applied to municipal catch basins and selected municipal sites with regularly occurring stagnant water.
Larviciding begins in early June and continues until the end of September.
Not all mosquito breeding sites will be treated with larvicides as some sites have mosquitoes that are not important in West Nile Virus transmission or contain mosquito types that are poorly controlled by larvicides.
To comply with Ontario regulations, Peel Region informs residents at the beginning of the season of larvicide applications through a notice in local newspapers.
Residents may sign up to have a free larvicide treatment applied to catch basins located on their residential property (for example in backyards).
Sign up for email notifications of positive West Nile Virus activity in Peel.
Activity in Peel (2025)
| Total | Brampton | Caledon | Mississauga | |
|---|---|---|---|---|
| Confirmed human cases | 0 | 0 | 0 | 0 |
| Probable human cases* | 0 | 0 | 0 | 0 |
| West Nile Virus positive mosquito batches | 0 | 0 | 0 | 0 |
*Probable human cases – confirmatory laboratory testing pending
Last updated: January 6, 2025
The table with human cases and positive mosquito batches will be updated regularly during the West Nile virus season from June to end October.
Lyme disease is a bacterial illness that is spread to people and animals through black-legged tick bites. Many species of ticks exist in Peel, including the black-legged tick, commonly known as a deer tick. Only black-legged ticks can spread Lyme disease to people and animals.
Ticks are found in tall grass, bushes, or wooded areas, including campsites, hiking trails, city gardens and parks. Learn more about Lyme disease.
If a black-legged tick has bitten you, you may be at risk of developing Lyme disease. Talk to your health care provider or ask your pharmacist about antibiotic medication to prevent the development of Lyme disease.
Learn how Public Health Ontario is monitoring Lyme disease.
Lyme disease and pets
Pets can encounter ticks during walks in grassy or wooded areas. The best way to protect your pet is to avoid areas known to have an active tick population and to keep your dog on a leash in heavily wooded or natural areas.
Talk to your veterinarian or get tips to prevent ticks on your pets.
Tick testing
If you have a tick that you would like to be identified, refer to etick.ca, a free on-line tick identification service.
Refer to Public Health Ontario for information on other diseases transmitted to people from animals or insects.
Bed bugs are small insects that feed on human blood by biting at night. You may not be aware that you have bed bugs in your home because bed bugs prefer to hide in dark, small spaces and some people have no reaction to bed bug bites. Signs of a bed bug infestation may include:
- Red bumps or welts on your skin
- Live or dead bed bugs, or bed bug skins
- Dark brown spots, or rust-coloured blood smears in the seams and crevices of mattresses, box springs, headboards, chairs, and other sleeping areas.
While bed bugs are unpleasant, they are not considered a public health risk because they are not known to transmit diseases. Learn more about bed bugs including how to prevent an infestation from Health Canada.
If you are not sure if the insect in your home is a bed bug, you can call Peel Public Health and an inspector can answer your questions.
Help with infestations
Getting rid of bed bug infestations usually requires the use of pesticides.
Only licensed professionals should apply pesticides for bed bugs. Working with a licensed pest control company will help protect your health and safety by ensuring the risk of pesticide exposure is minimized, the environment is protected, and the effectiveness of the treatment is maximized.
There are many licensed pest control companies in Ontario who have the proper training and experience to manage a bed bug infestation.