Residents can take certain precautions to avoid being bitten.
Officials are asking residents to take precautions after the West Nile virus was detected in a mosquito trap in York Region.
According to a press release, the infected mosquitos were discovered in Markham near Steeles Avenue East and Bayview Avenue.
The Regional Municipality of York monitors West Nile virus activity through mosquito traps and frequent testing for the virus.
"West Nile virus can cause serious illness and is passed to humans if they are bitten by an infected mosquito," said Dr. Karim Kurji, York Region's medical officer of health.
"Although the chance of being bitten by an infected mosquito is rare, residents are advised to take precautions when outside in the early morning and evening to prevent mosquito bites and reduce the chance of getting West Nile virus."
The best ways to protect yourself according to York Region are to "clean or remove standing water sources, including bird baths, flower pots, empty containers, clogged eavestroughs, swimming pool covers and outdoor toys like sand and water playsets or kiddie pools."
They also recommend you "ensure the window screens on your home are tight-fitting and in good repair."
When going outdoors they suggest to "use insect repellent containing DEET or icaridin – check label directions for use. Wear protective clothing, including socks, long-sleeved shirts and jackets. Dress with lighter colours if possible as mosquitoes are attracted to darker colours. Minimize outdoor activities at dusk and dawn when mosquitoes are most active."