Rabies: What to know about the virus in Canada
Risk to humans is low but if you don't get suspicious animal bites checked out it could be fatal
Natural resources officials in Newfoundland and Labrador are on alert after a rabid wolf nearly attacked two families in western Labrador and are asking the public to report any sightings of animals acting strangely.
The provincial department says the incident is the first case of rabies in the region since last summer. Across the country, the virus can be common or not, depending on the province in which you live.
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Here’s what you need to know about rabies in Canada.
What is rabies?
It’s a virus that can infect domestic and wild animals and can be spread to humans. Rabies attacks the central nervous system and eventually makes its way to the brain. The disease occurs throughout the world, except Antarctica and a few island nations.
How common is rabies?
The Canadian Food Inspection Agency reports that in 2014, there were 92 confirmed cases of rabies in animals — bats, skunks, foxes, dogs and other warm-blooded animals — mostly in Saskatchewan and Ontario. Bats in Ontario made up about one-fifth of all animal rabies cases.
The risk in people is if you are bitten and you never report it to anybody so no treatment was given.- Dr. Hugh Whitney
"In Canada, the overall risk of getting rabies from a domestic or wild animal is pretty low," says Dr. Allan Grill, a family physician and assistant professor at the University of Toronto.
Since 1924, 24 people have died across the country, says the Public Health Agency of Canada. More recently, there have been only four cases of human rabies in the past 30 years.
How is rabies spread to humans?
The virus travels through the saliva of infected animals, usually as a result of bites, scratches or licks on broken skin. The vast majority of people who become infected were bitten or scratched by an animal, with the face and upper body being the riskiest areas.
However, there are also some cases of organ or tissue transplants, where the virus was transmitted via the transplant.
The virus spreading among humans is very uncommon.
“Person-to-person transmission is theoretically possible, but rare and not well-documented,” according to the Public Health Agency of Canada website.
The agency says the risk for children becoming infected is estimated at four times higher than adults. Boys are also at a highter risk than girls.
Why is rabies dangerous?
Almost all cases of clinical rabies (that is, when symptoms start to show) are fatal, according to the public health agency. But the vaccines are "very effective."
Exposed people who get treated with a post-exposure prophylaxis vaccine right away often do not get sick.
“The risk in people is if you are bitten and you never report it to anybody so no treatment was given,” says Dr. Hugh Whitney, chief veterinary officer for the Newfoundland and Labrador government.
“If you start to show the signs of rabies, at that point, it is usually too late to do anything about it and you die.”
University of Toronto's Grill says any exposure to a wild animal, or even a strange domestic animal, could pose a risk of contracting rabies.
The virus goes into the nerves — a “very slow movement,” says Whitney.
“If [an animal] is bit in the hind leg, you can just imagine that’s a fairly long distance to go through the nerves, up the hind leg, along the spine into the brain. And once it hits the brain, that’s when you get the change in temperament.”
How should you vaccinate against rabies?
“Anybody whose occupation puts them at a higher risk than the general public for rabies, we get vaccinated beforehand,” says Whitney.
Veterinarians also get their blood sampled regularly to ensure there are enough antibodies.
If you get exposed to the virus, the public health agency says five doses are needed — the first as soon as possible and then on days three, seven, 14 and 28 after that first dose. About 65 per cent of yearly vaccine doses in Canada are used for post-exposure.
What happens if you get infected?
Firstly, if you’ve been bitten by an animal and you think you might have been exposed to rabies,the agency says you should immediately wash and flush the wound with soap and water.
Then, Grill says it's "extremely important" to immediately seek medical attention and contact public health officials to get advice on treatment.
"The reason why it's so crucial," says Grill, "is because if the proper treatment is given early before symptoms develop, the disease is entirely preventable."
Symptoms can take 20 to 60 days to appear, depending on a number of different factors such as the severity of the wound, where the wound is in relation to your nerves, the strain of rabies and how much protection was provided by your clothes.
Much like in animals, human rabies is spread through the nerves.
“It is considered to be one of the worst diseases, human diseases, because you go in and out of consciousness and you’ll have hallucinations,” says Whitney.
“People talk about Ebola as being a very bad virus, which of course it is. But people infected with rabies — if they get sick — have a much higher ... case fatality rate.
“We’re just very fortunate that there aren’t that many human cases of rabies.”
Clarifications
- This story originally contained information attributed to Dr. Hugh Whitney suggesting that people in areas where rabies exists in the animal population get vaccinated on a regular basis. In fact, Dr. Whitney says that in Canada, only people whose occupations put them at a higher risk in rabies infected areas should be considered for pre-exposure immunizations. This includes employees in a veterinary clinic, diagnostic laboratory, wildlife officers, animal care facilities, and people working with bats, for example.Feb 03, 2015 3:37 PM ET