As summer turns to fall, the weather across Canada is changing quickly.
There’s an age-old myth that a drastic drop in temperature can make you sick, but according to experts, it’s just a fallacy.
“That’s completely untrue,” said Dr. Isaac Bogoch, a researcher at the University Health Network and infectious disease expert.
“Infections — what we call upper respiratory tract infections — can occur all year round.
“The fact that it’s cold outside doesn’t mean that someone’s going to get a cold. The fact that it’s cold outside means that the season is changing, and there are some infections which become more viable in the winter months,” Bogoch said.
Catching a cold has nothing to do with the temperature
In order to catch the common cold, you have to come in contact with that infection — and that’s just as likely to happen in June as it is in December.
But it can seem like more people become ill in the colder months, a phenomenon Bogoch said could be caused by closer proximity to others.
“In the winter months, we tend to stay indoors more,” he said.
“We tend to huddle together more, and there’s probably more opportunities for people to transmit infections from person to person.”
WATCH: Health experts warn of a potentially bad flu season
There could be some loose evidence to suggest the immune system may not function as well in cold temperatures compared to mild temperatures, but Bogoch is wary of this theory.
“That’s not a strong belief among everybody [in the medical community]. The data suggesting that isn’t robust,” he explained.
“Even if we’re exposed to viruses or bacteria, we have a variety of mechanisms to clear these from our body … to either attack them or sweep them out of the lungs … and prevent them from spreading throughout our body.”
‘Flu season’ is real
However, it’s true that some viruses circulate more often at certain times of the year while other viruses circulate year-round.
One common infection that has “seasonal variation” is influenza, or what’s known as the flu.
Bogoch said beginning around late November, there’s a spike in the number of influenza cases across the country. “Flu season” typically runs until late February or early March.
“This will happen with high degrees of predictability,” he said. “It’s seasonal but it’s not to say that people can’t get sick [with the flu] throughout the year. They certainly can.”
When Canadian experts want clues on what our flu season might look like, they often look south, said Alyson Kelvin, an assistant professor at Dalhousie University in Halifax and an influenza virologist at the Canadian Centre for Vaccinology. She previously told Global News experts look at Australia, which experiences its flu season during our summer (and its winter).
“We can kind of look to see what’s going on there, and generally, there are trends seen in our later flu season,” she said.
There’s no ‘silver bullet’ for avoiding a cold
Despite common myths about tricks to “boost your immune system,” Bogoch said there are only two tried-and-true ways to avoid getting sick: wash your hands and get the flu shot.
“In terms of immune-boosting… a healthy lifestyle is probably the best thing you can do,” he said.
“Exercise, sleep and nutrition — these are the things that help our bodies function at their peak performance. By addressing all these issues, we really set ourselves up for success.”
Get your flu shot
The best thing you can do to protect yourself and others from the flu is getting your flu shot.
“The flu shot is useful for everyone in terms of reducing either the chance of getting influenza, and also, if you do get it, it should reduce the severity of it by giving some primed immunity to the virus itself,” Dr. Michelle Murti, a public health physician with Public Health Ontario, previously told Global News.
“As soon as the vaccine becomes available, that’s our No. 1 thing to say, that people — particularly those who are at high risk for influenza — should be getting the flu shot,” Murti said.
That includes people over 65, children under five, pregnant women and people with underlying health conditions like heart disease, respiratory disease, diabetes and obesity.
If you’re in one of these high-risk groups that could potentially have a more severe reaction to the flu, she said, you might even want to consider consulting with your physician before flu season starts to figure out a plan of action should you get sick. This could include things like having easy access to a prescription for antiviral therapy.
Aside from the flu shot, you should also wash your hands frequently, cough into your elbow or sleeve instead of your hand and stay home if you’re feeling ill, she said.
If you’re sick with a respiratory illness and you’re feeling short of breath, have a persistently high fever or have an illness that goes away after a few days but then comes back hard, Dr. Gerald Evans, chair of the Division of Infectious Diseases at Queen’s University, says these are all signs that you should visit a doctor.
— With files from Leslie Young