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How it started vs. how it’s going: What we’ve learned about COVID-19

A man wearing a plastic bubble walked along William J. Day Boulevard in Boston on March 12, 2020. The man, who asked not to be identified, said he found the contraption in a friend's yard and thought it would protect him from the coronavirus.Craig F. Walker/Globe Staff

When states first started issuing stay-at-home orders to combat the coronavirus in early 2020, Andy Freed assumed the shutdowns would be short.

“Prepare to be home for as long as two weeks,” Freed, CEO at Virtual Inc., a consulting company in Wakefield, wrote to his staff. Those two weeks turned into two years.

The office was closed from March 16, 2020, to March 16, 2022.

Like almost all Americans, Freed never imagined that we’d still be living with COVID-19 — and never expected to learn as much as he has about viruses, vaccines, and variants.

As the sun sets on the third summer of the pandemic, here are a few things we thought we knew about COVID-19 at the start — and how they compare with what we have learned since.



At the beginning of the pandemic, transmission was at the top of the list of unknowns: What was contaminated by COVID-19 — the air we breathe, the food we buy, the doorknobs we touch, the packages we open, or all of the above?

“We just didn’t know what was going on,” recalled Wendy Ernst, 66, a teacher from Lexington.

Living in lockdown without an answer, Ernst was among those who adhered to the most puritanical precautions.

“We’re going to bring the groceries inside, we’re going to put them in one place, we’re going to wipe everything down, and we’re going to wash our hands afterward,” she instructed her household in March 2020.

In April 2020, a study in the New England Journal of Medicine found that the virus lived up to 24 hours on cardboard and up to 72 hours on plastic or metal — which fostered fears about contracting COVID-19 from groceries.

Over that summer, some scientists said they were skeptical about the real risk of transmission on such surfaces, which they called “exaggerated.”


But it was many months until the Centers for Disease Control and Prevention confirmed that conclusion in April 2021 with definitive data: “Each contact with a contaminated surface has less than a 1 in 10,000 chance of causing an infection.”

Thus ended the era of Clorox-on-the-cereal-box.

Though the steps “seem a bit silly in hindsight,” Ernst said she doesn’t blame herself — or anyone else — for the extreme efforts.

“We did the best we could with the information we had,” said Ernst. “But I’m really glad that we don’t have to do that anymore.”

Mutations and Variants

Early in the pandemic, most experts claimed that coronavirus mutations weren’t cause for concern.

“In that first year of the pandemic, when we talked about variants, we thought this virus doesn’t change much genetically,” said Dr. Michael Osterholm, the director of the Center for Infectious Disease Research and Policy at the University of Minnesota.

But in December 2020, variants twice as transmissible as the original strain were detected on multiple continents — B.1.1.7 in the United Kingdom and B.1.351 in South Africa.

For Osterholm, the emergence of these variants — which came to be known as Alpha and Beta, respectively — caused a “sea change.”

“That’s where, for me, I had to make a major adjustment in how I was looking at the pandemic,” he said. “There were major changes occurring in transmissibility and in potential to cause serious illness.”

Dr. Peter Hotez, co-director of the Center for Vaccine Development at Texas Children’s Hospital and dean of the National School of Tropical Medicine at Baylor College of Medicine, said mutations have been among “the most frustrating parts” of COVID-19.


At first, the mutations were predictable, with “similar types of amino acid substitutions,” he said. But Omicron was a “game changer.”

The new variant, which emerged around Thanksgiving 2021, had “significantly more mutations” than previous versions, particularly in the gene that encodes the spike protein that the virus uses to attach to cells, according to the US Food and Drug Administration. As a result, Omicron and its subvariants are adept at avoiding the antibodies people produce after vaccination or infection.

Osterholm said scientists are “still trying to understand” why these mutations occurred as the virus replicated inside humans.

“We’re part of a natural experiment where that virus is going through all these genetic changes in us,” he said.

It’s impossible to anticipate how much more the virus might mutate in the future, and that might prolong the pandemic.

“Today, we still have a challenge of understanding what is going to happen in the future,” said Osterholm. “Is there going to be a BA.8? Is there going to be a BA.9? Is there going to be Pi or Sigma?”

‘Herd Immunity’

For much of the pandemic, experts claimed COVID-19 would stop spreading once we reached the tantalizing threshold of “herd immunity.”

The concept is simple: once the majority of a population is immune to a virus — by infection or vaccination — there are too few hosts for the virus to continue to spread in the population.


In March 2020, Osterholm declared in the Washington Post that COVID-19 was bound to disappear “eventually” — either through vaccination or through an accumulation of immunity against the virus.

“The virus will burn itself out as the spread of infection comes to confer a form of herd immunity on the population,” he wrote.

Today, Osterholm believes the opposite.

He first felt “skeptical” of herd immunity in August 2020 after a report of reinfection indicated that immunity could wane. Once the variants took over, he said, “all bets were off.”

“All the nails have been appropriately placed in the coffin of herd immunity,” he said.

The concept of herd immunity only works for diseases like polio and measles because those viruses are “not evolving fast,” said Hotez. For COVID-19, “with all the escape mutants, herd immunity proved a totally worthless concept.”

Others argue that we have, in fact, achieved a kind of herd immunity.

“We can see that there is some immunity out there, and it is interfering with the transmission of the virus,” said Dr. William Hanage, a professor of epidemiology at Harvard’s T.H. Chan School of Public Health. “It’s just not interfering with the transmission of the virus to make it go away.”


Above all, individuals who have charted the course of COVID-19 have come to understand uncertainty.

“One of the things that we’ve all learned is how certainty is elusive,” said Freed. “At the beginning of the pandemic, everyone strove for certainty. When are we going to be back in the office? When is this going to happen? And a lot of companies got burned in that quest for certainty.”


As a result, he said, “everyone in the business community — and broader — has gained a new appreciation for the uncertainty and the ongoing evolution that is part of medicine and science.”

Osterholm thinks that scientists should try to be more transparent about what they don’t know, especially when they are asked for predictions about the pandemic.

“If there were three words right now that more public health practitioners needed to adopt, it would be ‘I don’t know,’” he said. “We have to say, we don’t know, but this is what we’re doing to try to find out.”

Some of the changes to the virus — surprises that “Mother Nature herself is throwing at us” — are impossible to anticipate, said Osterholm.

“Who could have predicted BA.5 was going to come along? What is the BA-whatever of tomorrow or next month? What is the new variant? What does Pi or Sigma look like?” he said. “Without knowing that, it’s virtually impossible to make estimates that are fair.”

At this point, the only thing that he predicts is the unpredictable.

“This virus is going to continue to throw to 210-mile-an-hour curveballs at us, so get ready,” he said. “It’s not done with us just yet.”

Camille Caldera was a Globe intern in 2022.Follow her on Twitter @camille_caldera.