Wet Weather Leads to More Mosquitoes

Written by Comms Team, July 9, 2021

Risk of West Nile Virus May Be Higher

With wet weather in the forecast, Peterborough Public Health is advising residents to take extra precautions avoiding mosquito bites this season to prevent the risk of a West Nile virus infection.

“We could see more mosquitoes this year so it’s even more important to protect yourself by cleaning up and covering up,” said Wanda Tonus, Public Health Inspector.  “Meanwhile we continue to look for evidence of West Nile virus throughout the city and surrounding county and monitor its spread in Ontario.”

Peterborough Public Health staff trap mosquitoes at various locations in the summer as well as test for the presence of larvae from standing water found throughout the Peterborough area. In 2020, staff collected more than 5,000 local mosquitoes and had three pools test positive for West Nile Virus.  In 2020, Public Health Ontario reported that 171 positive mosquito pools and 77 confirmed or probable human cases of West Nile virus were recorded in Ontario. Human cases of West Nile virus have been reported locally in 2020 and 2017, and neighbouring areas in 2019 and 2020 within Haliburton, Kawartha, Pine Ridge District Health Unit and in 2020 within Hastings Prince Edward Public Health.

How do you protect yourself?

Clean up:

  • Continually empty standing water to remove the habitat that mosquitoes need to lay their eggs per the City of Peterborough By-Law, 03-107. This includes flower pots, wheel barrows, pool covers, old tires and garbage/recycling cans and other places that might inadvertently create a puddle or body of still water.
  • Fill in low depressions in your lawn to prevent puddles.
  • Change water in bird baths at least once a week.
  • Clean out dense bushes and shrubs where mosquitoes can rest.
  • Turn over compost pile on a regular basis.
  • Ensure window and door screens fit tightly and do not have holes.

Cover up:

  • Stay indoors at dusk and dawn because mosquitoes are most active during these times.
  • Use a bug repellent containing DEET, following the manufacturer’s instructions.
  • Cover up with light coloured, long clothing. This includes long-sleeved shirts, long pants, and socks. Also, wear footwear that covers exposed skin.

What are the symptoms of West Nile virus?

Approximately 80% of those infected with West Nile virus are asymptomatic (i.e. do not show any symptoms). Of the 20% that do, most experience mild illness with symptoms such as:

  • Fever
  • Headache
  • Body aches
  • Fatigue
  • Skin rash
  • Occasionally, vomiting and nausea

However, about 1% of those infected with West Nile virus may experience severe illness involving the central nervous system.  In its most serious state, West Nile virus infection can cause an inflammation in the brain, otherwise known as encephalitis.

For more information on mosquitoes and West Nile virus please contact the Vector Borne Disease Program at Peterborough Public Health at 705-743-1000, ext. 497.


For further information, please contact:
Brittany Cadence
Communications Manager
705-743-1000, ext. 391