What Have We Learned?

What has the pandemic taught us? Andre Picard writes:

For the longest time, we didn’t take viruses (and other pathogens that cause infectious disease outbreaks) all that seriously. Indeed, one of biomedicine’s most infamous and oft-quoted declarations is that “it is time to close the book on infectious diseases and declare the war against pestilence won.” But while the line itself is actually an urban legend – the man it was widely attributed to, former U.S. surgeon general Dr. William H. Stewart, never said it – the overconfident sentiment behind it is all too real, and all too common.

COVID-19, though, has been humbling. It has challenged many of our assumptions about viral illnesses. That a coronavirus, a type of virus that usually causes colds, could kill millions – 6.7 million deaths worldwide, by the official numbers – was unexpected. That the virus could leave countless more with potentially permanent sequelae in the form of long-COVID – even more so.

The mitigation measures that were undertaken, at least in the early days of the pandemic – such as lockdowns, working from home and masking – also created an unprecedented living laboratory that produced some eye-opening findings. By dramatically reducing social interaction, we all but eliminated influenza and other respiratory illnesses in 2020 and 2021. But they came back with a vengeance in 2022.

With all of this experience behind us, some of us have learned the wrong lesson:

Some have taken this to mean that getting infected with viruses is actually good for us, because it strengthens the immune system. This is one of the many ideas that has fallen under the too-broad, unscientific umbrella term of “immunity debt.” But this thinking is wrong. There is no evidence of any such “debt” that needs to be paid.

What is the right lesson?

The lesson is that we should not see infections as inevitable. We have tools to prevent them, from masking to vaccination, and we don’t use them effectively. At the very least, we can reduce harm by not letting viruses run wild.

Yet, flu vaccination rates are poor, even for those at highest risk, such as elders and young children. COVID-19 booster uptake has been middling.

The current “tripledemic” that is hammering children and filling up pediatric hospitals is also a reminder that no illness exists in isolation.

If anything, COVID-19 infections may have caused immune dysregulation that makes people (particularly children) more susceptible to other infections.

This may explain why Canadians are seeing not only surges in strep A (a bacterial infection that is usually mild), but also rare invasive cases that prove deadly. Same goes for the outbreaks of scarlet fever (also caused by strep A) and chickenpox we’ve seen in some countries.

Unfortunately, we can expect what is happening to children to happen among the elderly, another high-risk group. We are already seeing outbreaks of influenza, RSV and strep A in nursing homes, which have already been devastated by the pandemic.

In some ways, these more recent viral challenges have distracted us from the main event: COVID-19. While we largely returned to “pre-pandemic” normalcy this year, this has actually been the deadliest year yet for COVID-19; in 2022, Canada will surpass 17,000 deaths, more than the 14,642 deaths we recorded in 2020 or the 16,489 in 2021. A fifth wave of Omicron is just beginning.

So, what have we learned? First, viruses are not going away. And second, we have to use the tools we have -- over what could be a very long run -- to save lives.

Image: Britannica