You'll likely catch COVID-19 again and again. Will each round feel milder?

By this point in the pandemic, you've likely had COVID-19 at least once. Maybe twice. Perhaps even three times, as some unfortunate Canadians have experienced, all while this virus evolved to become increasingly savvy at infecting us.

It's clear that reinfections from this coronavirus are the norm, much like with those behind the common cold. Unfortunately, that also means early speculation about one-and-done bouts of COVID-19 offering immunity against future infections has long gone out the window.

What's more hazy is just how often you can get infected with SARS-CoV-2 and whether future infections will always be milder than the first, as the virus finds a way into our bodies over and over again.

Reassuringly, scientists say that for most healthy adults — including those with extra protection from vaccination — COVID-19 infections should get easier to deal with as your immune system gains repeat training on how to handle this particular pathogen.

"Your first infection with COVID is probably — not invariably but probably — going to be the worst," said infectious diseases specialist Dr. Allison McGeer, a professor at the University of Toronto's Dalla Lana School of Public Health.

"And then as you get more and more exposed to it, you get better and better protections."

After months or even years of avoiding the virus entirely, it might come as a surprise that COVID-19 can hit you more than once.

Early in the pandemic, some scientists spouted hopes around herd immunity — that if enough people caught COVID-19 or were vaccinated against it, collective immunity against infection would reach a threshold where the virus wouldn't be able to find new human hosts.

Unfortunately, that's not easy with a coronavirus.

First identified in humans in the 1960s, viruses in this family have likely been striking us repeatedly for centuries. SARS-CoV-2 is just the newest kid on the block.

"Four of those other family members cause about 30 per cent of our common colds, and they reinfect us routinely," said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security in Baltimore.

"We've all had multiple bouts of other coronavirus infections, and that's where this virus was always headed. So reinfections are not something to be surprised about."

They were rare, though, throughout the early part of the pandemic. SARS-CoV-2 is hitting people again and again at this point, two-and-a-half years in, partly because we're giving it the chance.

"This would have been happening much more frequently had we not all been staying at home and keeping our distance," McGeer said. "It's not that the virus is doing anything different than the virus would have done before; it's that we're behaving differently."