Yes, Omicron is Loosening His Attitude. But the epidemic is not over.


After a frenzied few weeks in which the Omicron variant of the coronavirus seemed to be infecting everyone, including those vaccinated and augmented, the United States is finally seeing encouraging signs.

As cases dwindle in parts of the country, many are beginning to hope that this increase is the last great battle with the virus – the Omicron variant, due to its unique properties, will save Americans from the pandemic.

The variant rose in South Africa and the UK, then fell sharply. Twitter is worried about charts showing virus levels falling in sewers in Boston and San Francisco. On Monday, the WHO’s senior European regional official suggested that “Omicron offers reasonable hope for stability and normalization”.

The Biden administration’s chief advisor on the pandemic, Dr. “Things are looking good,” Anthony S. Fauci said on Sunday. We don’t want to be overconfident, but they seem to be heading in the right direction right now.”

What drives optimism? The idea is that so many people become immune through vaccination or infection with Omicron that soon the coronavirus will find no place in our societies and will disappear from our lives.

But in interviews with more than a dozen epidemiologists, immunologists, and evolutionary biologists, the virus’s course in the United States appeared more complex and somewhat less rosy.

By infecting so many people, Omicron undoubtedly brings us closer to the end of the pandemic, they said. The current rise in infections is receding and there is reason to hope that hospitalizations and deaths will increase.

The road to normalcy may be short and direct, the goal may be only a few weeks away, and the dire fluctuations may be a thing of the past. Or, as the virus continues to gain ground, it could be long and bumpy with epidemics over the coming months and years.

In any case, many scientists said that the complete disappearance of the coronavirus is unlikely and herd immunity is now just a dream. The immunity of the population to the virus will be imperfect for various reasons.

“Perhaps there was a short period of time before we could reach that goal,” said Shweta Bansal, an infectious disease modeler at Georgetown University. But at this point, we’re way beyond that,” she said.

Instead, the coronavirus seems likely to become endemic – a permanent part of American life, a milder illness like the flu that people must learn to live with and manage.

But the future also depends on a wild card: new variants. Omicron only appeared at the end of November. Most researchers believe other variants are coming, as very little of the world has been vaccinated. Eventually, some can be both highly contagious and short-circuit the body’s immune defenses, prolonging everyone’s suffering.

“It’s your pick your own adventure, and the end hasn’t been written yet,” said epidemiologist Anne Rimoin of the University of California, Los Angeles. “No one can tell us what will happen.”

As of Wednesday, the United States was reporting more than 650,000 new cases daily, averaging more than 800,000 two weeks ago. Deaths continue to rise by an average of more than 2,300 per day, but hospitalizations seem to be approaching a plateau, with an average of 155,000 per day.

In the best-case scenario, as these numbers drop, many Americans could soon regain most of their pre-pandemic lives. Perhaps in the Northeast in the spring, and possibly other regions later on, many Americans can go to work without masks, send their children to school, and socialize with family and friends without worry.

Only those at high risk from Covid due to their age, health or occupation will need regular boosters tailored to the latest variant.

“I think we can basically get back to normal with tests and vaccinations if we can keep people out of the hospital and if we don’t get too sick,” said immunologist Michel Nussenzweig of Rockefeller University in New York.

In the long run, most of us may experience a mild infection every few years, as with coronaviruses that cause colds but do not become seriously ill.

The idea that Omicron is the last stand of the coronavirus has tremendous appeal. That’s what everybody wants, what every scientist hopes for. But to get there, Americans need to be both lucky and smart.

An endemic virus does not necessarily mean a minor threat. Tuberculosis is endemic in India and other countries and kills more than a million people each year. Measles is endemic in African countries. This virus circulates at constantly low levels and periodically triggers large outbreaks.

At the beginning of the pandemic, health officials estimated that vaccinating about 70 percent of the population for coronavirus could make us cross the herd immunity threshold, meaning the coronavirus has become a negligible threat.

But the more contagious a variant is, the higher the percentage of vaccinated people required to reach the threshold. When the alpha variant appeared, the scientists revised the level to 90 percent.

How much of a threat the coronavirus will remain depends in part on the level of immunity the country maintains over time. This is a difficult assessment to make.

There are millions of people in the United States and elsewhere who have no protection against the virus and have no plans to get vaccinated. Booster vaccines are necessary to prevent Omicron infection, and only half of eligible Americans have received them.

What’s more, scientists know little about the strength or duration of immunity left by an Omicron infection, and they know that the protection against infections afforded by vaccines wanes after a relatively short time. (Hospitalization and protection against death remain strong over a longer period of time.)

If the population’s protection against the virus is as weak or temporary as possible, then Americans could continue to experience outbreaks so large that hospitals flooded for years. To get them under control, people will have to line up for annual coronavirus vaccines, perhaps in the fall, as they do with flu shots.

If the virus remains an endemic threat, the number of people vulnerable to it will also change over time. Young people in higher risk groups will age or develop conditions that put them at risk, and babies will arrive without immunity.

“We have a stream of sensitivities that allows future contagion, whether because of evolution, decline or population change,” said epidemiologist Adam Kucharski of the London School of Hygiene and Tropical Medicine. .

The widespread lack of vaccination in the United States and worldwide, combined with uncertainty about the strength of immunity left behind by Omicron, opens the door to the possibility of new variants. One day, one of them will be able to bypass the immune defense as well or better than Omicron did.

“I see Omicron as an example of what endemic Covid-19 looks like,” said Kristian Andersen, a virologist at the Scripps Research Institute in San Diego. “But that doesn’t end with the Omicron because future variants will emerge.”

Neither vaccines nor infections provide so-called sterile immunity, meaning the protection they offer weakens over time. Protection from a Delta or Omicron infection may not be as effective against new variants as the virus changes unexpectedly quickly and in unusual ways.

Viruses typically evolve in a ladder-like pattern, with each new variant evolving from the previous one. But the three riskiest strains of the coronavirus, Alpha, Delta, and Omicron, evolved independently. The coronavirus wasn’t building on previous work, so to speak—it reinvented itself over and over.

As more and more parts of the world are vaccinated, evolution will favor forms of coronavirus that can circumvent antibodies and other immune defenses.

“We might get another variant out of the blue that responds to a selection pressure that we didn’t really consider, or mutations that we didn’t really put together,” said University of molecular epidemiologist Emma Hodcroft. Bern, Switzerland.

Contrary to popular myth, the coronavirus is not guaranteed to evolve into a milder form over time. A virus can evolve to be less lethal if it kills or runs out of hosts to infect others before it can infect others. It doesn’t apply to the coronavirus either.

“To be completely frank, really depleting the human reservoir to infect wouldn’t kill us enough,” said Jeffrey Shaman, an epidemiologist at Columbia University. “And it certainly is transmitted from an infected person long before the virus dies.”

A highly contagious variant can wreak havoc on the healthcare system, even if the next variant is as mild or even milder than Omicron.

“When you have something as contagious as an Omicron, you don’t need it to be incredibly violent to really screw things up,” said epidemiologist Bill Hanage of the Harvard T.H. Chan School of Public Health.

The future will also depend on our risk tolerance, both as individuals and as a nation. The most relevant comparison is the flu virus, which has survived with humans for hundreds of years.

Like the coronavirus, the flu is primarily a threat to certain groups – in this case older adults, children under 5 and those with compromised immune systems.

The rest of the population takes little action. Businesses and schools do not require negative tests for people with the flu, and people do not wear masks to protect themselves from the flu. Only half of adult Americans choose to get vaccinated each year.

With the coronavirus, public health officials are grappling with what normal should look like, including what trades are acceptable. But they do acknowledge that swaps are coming.

“We don’t have a vision of what level of control we’re aiming for,” said Jennifer Nuzzo, an epidemiologist at Johns Hopkins University’s Bloomberg School of Public Health. “I just don’t think zero cases are targets for any of us.”

This month, a group of former President Biden advisers urged the administration to plan for a “new normal” that would require long-term living with the coronavirus and flu. Dr. Like Nuzzo, they argued that the administration should set targets for the number of hospitalizations and deaths that would trigger emergency measures.

Given how often the coronavirus has upset expectations, Americans should hope for the best – but be prepared to live a little longer with anything shorter than that.

Dr. “We all want this to end,” Shaman said. “But I think we need to be a little more agnostic in our approach to all this.”

“We don’t know,” he added. “We just don’t know.”



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