British Columbia

Disease-carrying mosquito found in British Columbia

A mosquito that is both invasive and able to carry a number of serious diseases has been found in stagnant water in the Lower Mainland.

Researchers say the invasive species is able to carry several serious diseases.

A female Aedes japonicus mosquito captured feeding in Metro Vancouver in May 2015. (S. McCann)

A mosquito that is both invasive and able to carry a number of serious diseases, including La Crosse encephalitis and West Nile virus, has been found in stagnant water in the Lower Mainland.

This is the first sighting of the species Aedes japonicus — native to Asia — in Western Canada and, scientists believe, was brought in from the U.S. as a result of human action.

According to a study published in the Journal of Entomology, the mosquito "could be a significant threat to the health of humans and domestic animals," and its population should be monitored.

They believe that the mosquito is now established in the Lower Mainland and will likely be found in other parts of B.C.

The species was discovered after a resident of Maple Ridge called a Vancouver hotline in July 2014, reporting mosquito larvae in stagnant water caught in a garden tarpaulin.

The mosquito larvae were discovered in this tarpaulin in a Maple Ridge Garden. (Journal of Medical Entomology)

Researchers from Simon Fraser University and Burnaby pest control company Culex Environmental Ltd. investigated and collected larvae of the species. Returning in February this year, they discovered over 200 adult mosquitos.

In late May, a female was captured 13 kilometres east of the site "taking a bloodmeal".

Although the study says the mosquito could pose a significant threat, Dr. Michael Jackson, one of its authors who works at Culex, told CBC News that right now, there's almost no risk to the public.

"[The mosquito] is capable of carrying particular diseases only if that disease is present, and none of the diseases it carries are present."

With files from Farrah Merali


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