Coronavirus FAQ: It's cold and flu season — and COVID season! How do I stay unsick?

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We've heard that colds and the flu could be more prevalent this year because they didn't spread much last year when we were all masked up and staying away from people. Does that mean our defenses — that is, antibody protection — is down? Would it be a good idea to keep masking up this winter? Or would it be better to let ourselves get sick in the hopes of boosting our immune systems?

It's certainly true that the flu did not spread much last year: Just .2% of respiratory specimens from clinical labs and public health departments participating in national disease surveillance tested positive for flu during the 2020-2021 season, according to the Centers for Disease Control and Prevention (CDC), compared to between 26.2% and 30.3% for the previous three seasons.

What that could mean for this year, however, remains something of a mystery since that kind of dropoff has not happened in recent times. Still, there are enough clues for doctors and public health officials to offer some pretty solid advice.

First, let's take a crash course in cold and flu infection: Like COVID-19, colds and flus are viruses. Getting infected with a virus (as the pandemic has taught us so well) depends on a few things: First, exposure. That could be through the air, a main method of transmission for COVID-19 and the flu, or by touching surfaces contaminated with germs shed by infected individuals (the way colds are often spread). So last October, when children returned to school in Hong Kong wearing masks and physical distancing, flu and COVID were kept at bay — but cases of rhinoviruses, which cause 10-40% of common colds, exploded.

But just because you're exposed to a virus doesn't mean you will get sick.

That's where antibodies come in: People who have been exposed to a virus in the past have more immunity to it. That's why kids tend to get sick more often than adults: They haven't had as much time to be exposed to a variety of viruses. So it is possible that people will have fewer antibodies to this year's flu strain because of last year's general lack of exposure, leading to a bad flu season — but it's also possible that previous exposures have built up some levels of antibodies. And a study published in June in the Journal of Experimental Medicine shows that exposure to one virus can even help prevent getting infected by another (specifically, the researchers found that the antibodies generated by a rhinovirus infection could halt replication of SARS-CoV-2, the virus that causes COVID-19).

It's unknown how many antibodies we have to different viruses, points out Abraar Karan, an infectious disease doctor at Stanford University. "But we should still have some immune response to past strains," he says.

And there's another way to build up antibodies: vaccines. That could make it especially important to get the flu shot this year, he notes.

But some people are asking: Would it be better to stop masking and hand sanitizing in order to increase your exposure to pathogens? In other words, to risk getting sick in hopes of generating more antibodies for the next go-round? Our experts say no.

"People try not to get the flu every year," Karan says, and that's probably a good thing. Getting sick is ... well, yucky. And flu can, in fact, be fatal.

And you don't have to actually develop flu or cold symptoms to cook up antibodies. Unless you never leave your house, you'll get plenty of exposure to germs, Karan says. And even when you don't get sick from the exposure, you still build up some antibodies.

So the challenge is: stay healthy and, if you fall prey to a virus, avoid infecting others.

And that brings us to a topic all too familiar in the COVID era: washing your hands!

"There's not really such a thing as being too clean," says Charlotte Baker, an assistant professor of epidemiology at Virginia Tech, adding that the pandemic was a wake-up call for many who don't wash their hands enough. "You should always keep your hands clean."

Although you should avoid using antibacterial soap when possible for other reasons (such as developing antibiotic resistance, which doesn't affect viruses), it's fine to keep using alcohol-based hand sanitizers, she says. That does not lead to antibiotic resistance.

Then there's the matter of not infecting others. That means staying home when sick and ... yes, wearing masks on occasion!

We could learn a lesson from other countries that wear masks and keep their hands clean, Baker notes. Those countries tend to have lower rates of flu, colds, respiratory illnesses and even asthma attacks, she says.

"There's a pretty good chance right now of running into someone with a cold, flu" or another respiratory virus, she says. Even when COVID-19 subsides, she hopes "people will still sit out if they don't feel well, wash their hands regularly and if you're around elderly or immunocompromised people regularly, wear a mask when you go out and about" — at least during flu season.

And if you top off those preventive measures with a healthy diet, exercise and keeping stress levels low, "you'll put yourself at a good chance of feeling better" if you do pick up a virus, Baker adds.

Masking up post-COVID can be an individual decision, Karan agrees. He plans on using masks even when he's outside of the hospital, depending on how much viruses are circulating – that applies to colds, flu and COVID.

Bottom line: "We don't want you to be sick!" Baker says. And getting a nasty case of a cold or the flu isn't necessary to improve your immune system.

Sheila Mulrooney Eldred is a freelance health journalist in Minneapolis. She's written about COVID-19 for many publications, including The New York Times, Kaiser Health News, Medscape and The Washington Post. More at sheilaeldred.pressfolios.com. On Twitter: @milepostmedia

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