First human case of West Nile in 2025 confirmed in Mississauga

The summer’s first confirmed case of West Nile virus in Mississauga has health professionals urging residents to protect themselves from mosquito bites.

Peel Public Health said on Tuesday that it has confirmed the first human case of West Nile virus of 2025 in a Mississauga resident.

The virus, which is transmitted to humans through the bite of an infected mosquito, was first found in Mississauga mosquitoes from a trap near Derry Road and Airport Road in July.

Officials say the risk of exposure to infected mosquitoes is highest between July and September.

RELATED: West Nile virus found in more mosquitoes in Mississauga and Brampton

Symptoms include flu-like symptoms such as fever, headache, body aches, mild rash, and swollen lymph glands. And while most people who contract the disease will show no symptoms, “rare cases” of West Nile can lead to severe illness, PPH says.

Here are some tips to help you avoid getting bitten by mosquitoes this summer:

• Wear a Health Canada approved insect repellent can help prevent mosquito bites, especially those containing an ingredient like DEET or icaridin.
• Use a mosquito net for babies or young children when outdoors, in a crib or stroller.
• Wear light-coloured, tightly woven, loose-fitting clothing such as long pants, a long-sleeved shirt, shoes, and socks to protect exposed skin.
• Avoid shaded or wooded areas with high mosquito populations and take extra precautions during dusk and dawn, when mosquitoes are most active.
• Ensure all windows and door screens fit securely and are free of tears and holes.
• Remove or drain items on your property that hold stagnant water.

The region says water that is stagnant for more than seven days is an ideal breeding site for mosquitoes. Residents in Mississauga and Brampton can report stagnant water sites to Peel Public Health at 905-799-7700, or toll-free at 905-584-2216 in Caledon.

Peel Public Health has confirmed the first human case of West Nile virus for 2025 in a Mississauga resident.
West Nile virus is transmitted to humans through the bite of an infected mosquito.

— Peel Region (@regionofpeel) September 9, 2025