Mosquitoes test positive for West Nile Virus in Niagara

July 21, 2025

Niagara Region Public Health has received its first confirmation of West Nile Virus in mosquitoes in 2025.

While the mosquitoes that tested positive were found in Welland, all Niagara residents are encouraged to take precautions to reduce the risk of being bitten by mosquitoes that could potentially expose them to West Nile Virus.

West Nile Virus is a mosquito-borne virus that can cause fever, headache, body aches, and in rare cases, serious neurological illnesses such as meningitis if a person is bitten by an infected mosquito. Most people infected with West Nile Virus do not show symptoms, but the risk of severe illness increases with age and those with weakened immune systems.

“Even though the risk to most individuals is low, it’s important to take steps to protect yourself and your family from mosquito bites,” says Dr. Azim Kasmani, Niagara Region Medical Officer of Health. “Simple actions like removing standing water and using insect repellent can significantly reduce your chance of infection.”

To help prevent mosquito bites and reduce the spread of West Nile Virus, Niagara residents should:

Wear long-sleeved shirts, long pants, socks and shoes when outdoors, especially at dawn and dusk when mosquitoes are most active
Use mosquito repellent containing DEET or Icaridin, and carefully follow the manufacturer’s directions
Drain areas of standing or stagnant water on your property regularly, including bird baths, old tires, pails, toys, and wheelbarrows
Ensure all windows and doors in your home have screens that are in good condition

As of this release, no human West Nile Virus cases have been identified in Niagara so far in 2025.

At Niagara Region Public Health, we run a mosquito surveillance, management and prevention program throughout the summer months to help identify and control the spread of West Nile Virus. We also promote public education on West Nile Virus and how residents can protect themselves.

Residents with inquiries about West Nile Virus can call 905-688-8248 ext. 7590 or 1-888-505-6074. Learn more about West Nile Virus.

Media contact

Celia Carr
Niagara Region Public Health
905-688-8248
celia.carr@niagararegion.ca