Fight the bite: Mosquito borne diseases are on the rise in Canada

Mosquito Season Brings Increased Risk

Summertime is mosquito season in Canada and mosquito bite prevention is more important than ever. In the years ahead, Canadians will likely face an increased risk of mosquito-borne diseases, like West Nile virus, due to climate change. Scientists at the Public Health Agency of Canada’s National Microbiology Lab (NML) explain how the increases in temperature, changes in rainfall patterns and decreased number of frost days create an ideal habitat for mosquitoes to live, breed and transmit disease in Canada.

Canadian Scientists Improve Mosquito Surveillance

The NML conducts mosquito surveillance, diagnostics and research on the emergence of mosquito-borne diseases in Canada to protect the health of Canadians. Dr. Robbin Lindsay, Senior Research Scientist at the NML, monitors the spread of West Nile virus and other mosquito-borne diseases across North America.

“Mosquito epidemics are driven by weather patterns,” explains Dr. Lindsay. “Weather variability may result in a northward spread of mosquito-borne diseases and could potentially facilitate the range expansion of new mosquito species that carry exotic mosquito-borne diseases like Zika virus, Dengue or Chikungunya.”

The NML is currently working alongside provincial and territorial health authorities to conduct weekly mosquito surveillance and monitoring to regularly assess the risk of mosquito-borne diseases in Canada. As the climate changes in Canada, Dr. Lindsay believes that a predictive forecasting tool, such as risk-area mapping, is the next step in mosquito surveillance.

Dr. Nicholas Ogden, Director of Public Health Risk Sciences at the NML, and his team, are working to develop forecasting methods, similar to weather forecasting, which will predict where and when there is a heightened risk of a mosquito epidemic. The Mosquito Borne Disease forecasting tool will assess risk based on the geographical location, environment (urban or rural community) and recent weather patterns.

“Alerts may encourage people to take mosquito prevention measures when the risk is high in their region,” explains Dr. Ogden. “Improved mosquito surveillance will help us create lead time for these awareness campaigns.”

The team is aiming to have this service available to Canadians in the coming years, as the risk of endemic mosquito-borne diseases continues to rise in Canada.

Fight the Bite: Mosquito Prevention Goes a Long Way

The majority of exposures to mosquito-borne diseases result in non-symptomatic or mild illness, although on rare occasions they can cause more severe symptoms, like paralysis or neurological disorders.

There is no vaccine or specific treatment for mosquito borne diseases, so reducing mosquito habitat and minimizing the risk of mosquito bites are the best ways to prevent infection.

Mosquitoes develop in still or very slow-moving water and some lay their eggs on the surface of the water. The larval and pupal stage live within these standing water environments for as little as 7 days up to many months. It is important to reduce mosquito habitat near your home by removing standing water.

In most parts of Canada, mosquitoes are common from May to September. Mosquitoes can bite at any time of the day, but they tend to be more active between dusk and dawn. Canadians are encouraged to protect themselves from mosquitoes by covering exposed skin (e.g. wearing long pants and loose-fitting shirts with long sleeves) and using insect repellent containing DEET or Icaridin.

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