Ontarians Reminded to Protect Themselves from West Nile Virus

Written by admin, August 3, 2012

August 3, 2012 – Mosquitoes Carrying The Virus Are On The Rise In The Province

Ontarians need to continue taking proper precautions to reduce their risk of contracting West Nile Virus as the number of mosquitoes with the virus is on the rise across the province, especially in Southern Ontario.

Eighty-nine positive mosquito pools have been found in the province to date, which is the highest for the same time period since 2002.

The province is also seeing probable and confirmed human cases of West Nilevirus, which typically start to occur in August and September.

Dr. Doug Sider,Ontario’s Acting Chief Medical Officer of Health, is reminding Ontarians to continue protecting themselves from mosquito bites by:

  • Wearing light-coloured clothing, long-sleeved shirts, long pants, socks and shoes when outdoors
  • Using insect repellent containing DEET, and following the directions carefully
  • Avoiding the outdoors at dusk and dawn when mosquitoes are most active
  • Repairing or replacing screens on windows and doors to avoid mosquitoes entering your home.

It is also important for Ontarians to reduce prime breeding grounds for mosquitoes by draining standing water from around their home on a regular basis.

Most people who contract West Nilevirus will not exhibit any symptoms or may experience mild illness including fever, headache, body ache, nausea, vomiting and rash on the chest, stomach or back.  More serious symptoms can include muscle weakness, stiff neck, confusion, tremors, numbness and sudden sensitivity to light.  Symptoms usually develop between two to15 days after being bitten by an infected mosquito.


“I encourage Ontarians to take proper precautions to avoid mosquito bites and prevent infection.  If mosquitoes can’t get to you, you won’t get bitten.”
— Dr. Doug Sider, Ontario’s Acting Chief Medical Officer of Health


  • Mosquito pools are catch basins set and monitored by local public health units across the province as part of aWest Nilevirus surveillance program. The mosquitos are collected and tested weekly.
  • One confirmed human case, one travel-related human case and four probable human cases of West Nile virus have been reported to date in Ontario this year.  
  • In 2011, a total of 78 confirmed and probable human cases of West Nile virus were reported.


Find out more about West Nile virus.

Tori Gass, Ministry of Health and Long-Term Care