Mosquito-borne virus spreading on the east coast, could come to Quebec

Another mosquito-borne virus is spreading in New England, and could soon make its way to Quebec.

It has been called the Triple- E - Eastern Equine Encephalitis, and it has already killed one person.

Quebec doctors are urging caution, as mosquito season is far from over despite summer coming to an end.

"The threat could still be there, and people should pay particular attention, especially if they're going to do activities like camping in nature," said infectious disease specialist Dr. Donald Vinh.

Viral transmission from mosquitos to humans is rare, but it can be deadly.

The New England resident died of complications caused by the virus in August.

Vinh explained that the virus can cause serious damage to people's nervous systems.

"The person can present not only with fever and headaches but also with confusion, convulsions or seizures," said Vinh. "They can be even comatose, or unfortunately, they can even die."

The virus's incubation period ranges from three to 10 days, starting off with flu and cold-like symptoms.

Although cases in humans are rare, it's not unusual for there to be cases among horses.

"In Quebec, the first important outbreak was found in horses in the first in outbreak in 1972," said Quebec Institute of Public Health (INSPQ) advisor Miarisoa Rindra Rakotoarinia.

The last important outbreak reported in Quebec for horses was in 2008.

Health Canada has reported four Triple-E human cases in Ontario, with the most recent reported in 2022.

The mosquito species that spread the virus, which is caught from biting birds that carry it, are found in regions including Lanaudiere, Rakotoarinia said.

The bugs, however, may expand to more regions as weather warms.

"With climate change we expect more flooding, more temperature rising - so that is favorable for mosquito development," she said.

About five per cent of people infected develop a neuroinvasive form of the disease, and some face higher risks, according to Vinh.

"People over the age of 65, yes, but also young children, infants and toddlers," said Vinh. "Certainly, people who are imunocompromised can also have the more severe form of the disease."

Vinh said the virus has been known to cause outbreaks along the eastern area of North America for 100, if not 200, years.

There is currently no vaccine or medical treatment for the viral infection.

"But they should seek medical attention because what we can give is medical supportive care to monitor and treat any complications that can develop from this infection," said Vinh.

In terms of prevention, Vinh recommends bug repellent, netting and wearing loose-fitting, long-sleeved shirts and pants.

"People can't forget the fact that birds and mosquitoes travel- they don't respect borders," he said.