Second Mosquito Trap Tests Positive for West Nile Virus in Perth County

Huron Perth Public Health is reminding residents to protect themselves against mosquito bites following confirmation that mosquitoes collected from a trap in St. Marys tested positive for West Nile Virus (WNV). This is the second positive mosquito finding of the season for Perth County, with the first reported just last week in Mitchell.

“It’s not surprising to see positive mosquito pools in the month of August,” says Kaitlyn Kelly, Public Health Inspector. “The second positive mosquito report serves as a reminder that WNV is present in our communities and it is important to reduce your risk of exposure to mosquitoes and protect yourself against bites.”

Mosquito Surveillance and Control Activities

The Health Unit has been trapping and testing mosquitoes in locations across Huron and Perth since June 8. To reduce the risk of potential WNV transmission, larvicide is being applied to roadside catch basins in Stratford, St. Marys, Listowel and Mitchell this summer to help reduce mosquito breeding.

West Nile Virus in Humans

In Ontario, no probable or confirmed human cases of WNV have been reported this year.  Not everyone who is bitten by an infected mosquito will show symptoms of the virus. Of those who do show symptoms, most will experience mild illness, including fever, headache, body aches, nausea, vomiting and rash on chest, stomach or back. About 1 in 150 people infected will get seriously ill, with symptoms like high fever, muscle weakness, vision loss and coma. WNV can lead to death.

Symptoms usually develop between two and 15 days after being bitten by an infected mosquito. People older than 50 are most at risk for WNV infection as are those with weakened immune systems.

Protect Yourself from Mosquito Bites

People can protect themselves from mosquito bites by:

  • Using an insect repellent when outdoors containing DEET or Icaridin. Be sure to follow the manufacturer’s directions.
  • Covering up with light-colored clothes, long sleeves and pants when outdoors or in areas where mosquito activity is high.
  • Taking extra protection measures at dusk and dawn when mosquitoes are most active.
  • Removing standing water around the home at least once a week to reduce mosquito breeding grounds.

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