The first mosquitoes to test positive for West Nile virus (WNV) in Ontario this year were trapped in the City of Peterborough from July 20 to 23.
The results were reported on Monday, July 27 by Peterborough Public Health, which sets traps weekly throughout the city and Peterborough County for testing in summer and early fall.
As of July 18, there were no positive results in the province and no human WNV cases, Public Health Ontario reported.
Bite prevention key
“Now that we’ve identified mosquitoes carrying West Nile virus in our area, it’s especially important that residents take care to prevent mosquito bites,” Peterborough Public Health Public Health Inspector Wanda Tonus stated. “This is a good reminder for residents to get rid of any standing water in their yards and to take precautions to avoid mosquito bites.”
The majority of WNV cases do not show symptoms, Tonus noted. About 20% of infected people may have a mild flu-like illness with fever, headache, and body aches, occasionally with a skin rash and swollen lymph nodes or other non-specific symptoms that last several days. Other symptoms may include nausea, vomiting, or eye pain.
Less than 1% of infected people will develop neuro-invasive disease, with older age groups and males disproportionately affected.
Although the risk of becoming infected is low, prevention against mosquito bites is the best protection, officials reminded.
How to protect yourself from bites
- Cover up when going outside between the hours of dusk and dawn. Remember to wear a long-sleeved shirt or jacket and long pants (tucked into your socks for extra protection) and light-coloured clothing
- If you will be outside for a long time, wear special clothing that is designed to protect you from bugs
- Use insect repellant containing DEET. (DEET is a powerful chemical. Always read the label directions for use. Or, ask your pharmacist for help when choosing a DEET product)
- Clean up: once a week, get rid of standing water around your home (mosquitoes lay their eggs in stagnant water, even small amounts); keep bushes and shrubs clear of overgrowth and debris (adult mosquitoes like to rest in dense shrubbery); and turn your compost pile often
Source: Peterborough Public Health
The City of Peterborough has completed one round of larviciding catch basins within its jurisdiction, and a second round is underway, officials stated.
Public Health Ontario reported 71 positive mosquito pools and 19 confirmed human cases of West Nile virus in 2019, down from 305 positive pools and 137 human cases in 2018.