Endemic vs. pandemic: What it means to 'learn to live with' COVID-19 – National Post

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Endemic is a slippery term, said infectious diseases historian Esyllt Jones. It’s meant to imply that a pathogen has become stable and predictable, less whirlwind, which isn’t a great way to describe where we’re at with SARS-CoV-2.

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What it doesn’t necessarily mean is less virulent, or “very low” or “not a problem.” And while Spain and other countries are pivoting to the “flu-ization” of COVID, it’s not clear yet whether SARS-CoV-2 will become flu-like, because it hasn’t yet settled into a seasonal niche and has been spreading among humans for only two years, said Ross Upshur, of the University of Toronto’s Dalla Lana School of Public Health. The virus is still evolving, it’s not clear where it’s headed, and it likely has plenty of genetic space to explore. Omicron came out of nowhere, and though it has been linked with “milder” infections, “There is nothing in evolutionary biology that necessitates the disease becoming milder as it passes through humans,” Upshur said.

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“So we need to really just keep vigilant and not just say, ‘It’s over. Yahoo.’”

The endemic narrative is more about what we desperately want, Jones and others have said — to just move on. “It’s endemic because we say it is, if you like.”

It’s endemic because we say it is, if you like

It’s time Albertans “begin to heal,” Alberta Premier Jason Kenney said this week as the province became the first in Canada to scrub its vaccine-passport scheme. Rules requiring masks in Alberta’s schools will end Monday. As of March 1, gone, too, will be the province’s work-from-home order, indoor mask mandates, capacity limits on most indoor venues and limits on social gatherings, provided hospitalizations are trending down. Saskatchewan, Quebec and Prince Edward Island are also moving to shelve restrictions keeping humans more distanced from other humans, evidence of what many are predicting — that the pandemic will have a sociological, and not biological, denouement.

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Real-time pandemic dashboards tracking cases, hospitalizations and death counts have led people to believe that we can call it when the numbers click down to zero, or, in the case of the proportions vaccinated, 100, Princeton University’s David Robertson and Peter Doshi, of the University of Maryland School of Pharmacy wrote in the BMJ.

But “there is no universal definition of the epidemiological parameters of the end of a pandemic,” they said. History shows pandemic endings aren’t sudden or dramatic, but unhurried, bumpy and uneven, they wrote, “and that pandemic closure is better understood as occurring with the resumption of social life, not the achievement of specific epidemiological targets.”

“It doesn’t end. We just stop caring. Or we care a lot less,” Johns Hopkins Bloomberg School of Public Health epidemiologist Jennifer Nuzzo put it more bluntly to the Washington Post. “I think for most people, it just fades into the background of our lives.”

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It doesn’t end. We just stop caring. Or we care a lot less

COVID-19 certainly isn’t fading to black. There are still nearly as many people in Canada dying every day as at any point except the first wave. The single-day death toll was 165 on Jan. 31, though the number has been falling since. As the National Post’s Tom Blackwell reported this week, deaths are occurring largely among the elderly, COVID’s most vulnerable prey. And while vaccines are still holding up well against serious disease and death, Omicron has caused several times the infections as previous waves. Infection rates are still elevated, activity still widespread, Canada’s chief public health officer reported Wednesday, though seven-day average case counts are falling. Globally, the seven-day average of reported cases is 2.6 million.

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Bill Hanage asks how the number of deaths in Canada has somehow become acceptable. It’s why the Harvard University epidemiologist has problems with the “new normal” and “we need to learn to live with it” narrative. What does it mean? “And who decides what that looks like?” Hanage said in an email. “At the basis of this is the notion that a certain amount of illness and death is acceptable, and that action is only merited to prevent those limits being exceeded.” As he summed it up succinctly in a tweet Wednesday, the non-scientific definition of endemic is basically “the amount of disease from which people are willing to avert their eyes.”

The technical definition implies a relatively stable rate of transmission in a defined geographic area, without huge waves ripping through the population. It exists in the population at some level, it fluctuates, but it eventually settles where it’s going to settle. But endemic doesn’t reflect severity, said Uphsur, of the U of T. “Hundreds of thousands of children die from malaria every year. That has been a stable phenomenon over time.” Tuberculosis, endemic in many places, also kills huge numbers.

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“The term carries a pretty high level of subjectivity,” Jones, the University of Manitoba historian said. It also tends to be fatalistic, “and reflects to some extent what amount of death is seen as normal and acceptable, for whom. It’s contingent.”

Hanage’s worry is that that fatalism will keep us from moving quickly, if things change quickly.

Additional outbreaks are not only possible but expected

How close to endemicity might we be? “We don’t know,” he said. It depends how robust and durable the immune responses are in people who have been vaccinated or recovered from infection, or both. “Neither enter a state where they develop lifelong immunity to infection, so additional outbreaks are not only possible but expected,” Hanage said.

“Of course, if you take the non-technical meaning of ‘endemic’ as ‘something we don’t really bother about that much’ — which applies sadly to the way most people think about malaria, TB and the like because they tend to be diseases associated with poverty — that makes it a decision for humans, and the point at which humans decide they’ve got an amount of disease they can handle.”

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The current thinking, said University of British Columbia evolutionary biologist Sarah Otto, is that we’ll see waves like this, like Omicron, though not as steep, and with a lower risk of hospitalization because of acquired immunity. “One thing that’s important to know, though: Those mild cases (from Omicron infections) don’t build a strong immune response. We’re seeing the best immunity in individuals who have been vaccinated, and then vaccinated with infection.”

Hanage said the sunniest scenario is that Omicron — “which don’t forget killed 15,000 Americans last week” — eases up in the next month or so, and that immunity generated by Omicron does turn out to be substantial, “such that when things pick up once more in the fall there are few severe infections.” While next winter won’t be fun for people who work in health care, neither will it be anywhere near catastrophic, Hanage said. Next-generation vaccines will hopefully offer sterilizing immunity, like measles shots, stopping all transmission and infection “and producing indirect benefits — the so-called ‘herd immunity.’”

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The grimmer scenario is that a variant emerges that blends Delta’s virulence, it’s ability to cause serious sickness, with Omicron’s ability to duck some immunity acquired from vaccines and past infections. “Exhausted, we are unable to counter it with non-pharmaceutical interventions and many are sickened and die,” Hanage said. “I am not saying this is likely. I think this is unlikely. But I would not exclude it.”

Still, even in the worst case scenario Otto sees a silver lining. “We can boost quickly. We know what measures we can go back to,” like masking or reducing capacity in large indoor events in crowded spaces. “We’ve learned a lot in the hospital — which treatments work best, how to maintain oxygen levels without intubation. Even the worst-case scenario has a rosy lining in just how much we’ve learned.”

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Upshur imagines SARS-CoV-2 will settle into a seasonal virus, though one “with a nasty edge to it, particularly in vulnerable populations.”

“We know this virus pops in and out of animal reservoirs,” he said. “I’m still not sold this was some kind of laboratory misadventure because we’ve seen it go into mink and zoo populations.” We need to heed the “One Health” approach that recognizes the health of humans, animals and the environment are linked, and enhance surveillance of viruses in animal populations that have the capacity to jump into humans, Upshur said. We need to shore up public health surveillance systems — more wastewater testing, more reporting and feedback from family doctors and primary care — “so that we can get an early indication that something is happening.” The more people on the planet left unvaccinated, the bigger the playground for the virus to continue to evolve variants. “We’re not safe until everyone is safe.”

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If we haven’t been living with this virus for the past two years, what have we been doing?

You can’t wish away a virus by honking horns, Upshur said. And the “learn to live with it” messaging is sloppy, he said. “If we haven’t been living with this virus for the past two years, what have we been doing? What is the intended meaning of ‘living with this?’

“Let’s be clear. Let’s try to be articulate. Let’s try to be sensible about what it is we’re trying to achieve in our pandemic response.”

In some ways, we are in the endemic era, said McMaster University immunologist Dawn Bowdish. “There is no chance that COVID will ever be eliminated from the population now, it has spread everywhere, there are animal reservoirs and new babies are being born with no immunity, therefore new hosts to infect.”

In our COVID future, there will be periodic outbreaks in cancer units and hospitals and long-term care homes, Bowdish said. Loss of life in vulnerable populations. “Endemic is not a synonym for ‘easy.’”

It’s not time to ignore COVID, Otto said. But it is time to redefine what normal means for each of us. She can’t remember the last time she shook someone’s hand. She pays attention to ventilation in a room. When cases are high, she puts a new mask on when she takes the bus, careful to make sure air isn’t escaping everywhere from the sides.

“We’ve all come to just kind of learn a new normal,” she said. “And that is protecting us quite a bit, and will continue to protect us in future waves.”

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