Virus variants threaten to pull out the epidemic, scientists say

For weeks, the mood in the United States has been far more frightening. Coronovirus cases, hospitalizations and deaths have decreased from their height, and millions of people are being newly vaccinated every day. Restaurants, shops and schools have reopened. Some states, such as Texas and Florida, have dropped precautions altogether.

In measurable ways, Americans are winning the war against the coronaviruses. Powerful vaccines and a rapid rollout guarantee an ultimate return to all but normalcy – for backyard barbecues, summer camps and sleepovers.

But it is clear that the next few months will be painful. The so-called variants are spreading, carrying mutations that make the coronavirus more contagious and in some cases more lethal.

Even vaccines were authorized at the end of last year, with variants roaming the UK, South Africa and Brazil, illuminating a path to the end of the epidemic. New variants continue to pop-up California in a week New York And Oregon next. As they take root, these new versions of coronovirus threaten to end the epidemic.

At the moment, most vaccines appear to be effective against variants. But public health officials are deeply concerned that a recurrence of the virus in the future may be more resistant to the immune response, causing Americans to queue up for regular rounds of booster shots or even new vaccines.

“We don’t have development,” said Devi Sridhar, professor of public health at the University of Edinburgh, Scotland. “This pathogen is always changing in a way that makes us harder to suppress.”

Health officials acknowledge the urgent need to track these new viruses as they crawl across the United States. Already, B.1.1.7, the highly contagious version that wallops Britain and wreaks havoc in continental Europe, is Growing fast In the United States.

Limited genetic testing has exceeded 12,500 cases, Many in Florida and Michigan. As of March 13, the variant accounted for 27 percent new Nationwide cases, down from just 1 percent in early February.

Biden administration has Mortgage pledged “down payment” of $ 200 million To ramp up surveillance, it is possible to perform an infusion to analyze 25,000 patient samples each week for variants of the virus. This is an ambitious goal: the country was sequencing just a few hundred samples each week in December, then increased to about 9,000 per week by 27 March.

Recently, until the rise of B.1.1.7 overall rates of infection had not been reduced, Americans were embroiled in a false sense of security and relaxed restrictions, researchers said

Sebastian Funk, a professor of infectious disease dynamics at the London School of Hygiene and Tropical Medicine, said, “The best way to think about B.1.7 and other variants is to consider them as distinct epidemics.” “We really like obscuring the scene by adding all those cases.”

Other variants identified in South Africa and Brazil, as well as some virus variants first seen in the United States, have slowed to spread. But they are also worrisome, as they contain a mutation that reduces the effectiveness of vaccines. This week, an outbreak of P.1 forced the closure of the Whistler Blackcomb ski resort in British Columbia, a version that crushed Brazil.

Scientists say that the world is stuck in a sprint between vaccines and variants and will eventually win. But because each infection allows the coronovirus to develop further, vaccination should proceed in the United States and elsewhere as soon as possible.

Infections are increasing again, driven to an indefinite degree by B.1.1.7 and other variants. Earlier this week, the director of the Centers for Disease Control and Prevention, Drs. Rochelle Wallensky told Americans to continue practicing masking and social disturbances, adding that she felt a sense of “impending doom”.

“We have so much to look forward to – so much promise and potential where we are and so many reasons for hope,” she said. “But I’m scared right now.”

The coronovirus must have slowed down to change shape. Like all viruses, it will pick up mutations and evolve into thousands of variants, scientists said at the beginning of the epidemic. But it wouldn’t change significantly for the year – a stupid virus, some called it.

Pathogen defined those predictions. Viral immunologist at Washington University in St. Louis, Drs. “We expected the virus to change,” said Michael Diamond. “We didn’t anticipate very quickly how soon this was going to happen.”

A variant is only of concern if it is more contagious, causes more severe disease, or blunts the immune response. Identified variants in the UK, South Africa, Brazil and California all meet the criteria.

B.1.1.7, the first to come to wide attention, is about 60 percent more contagious And 67 percent More deadly According to the most recent estimates, the origin of the virus.

The variant is not different from the origin in how it spreads, but infected people Seems to carry more of the virus And for a long time, Said Katrina Lythgoe, an evolutionary biologist at the University of Oxford. “You’re more contagious for more days,” she said.

So contagious is B.1.1.7 that Britain succeeded in reducing infection only after a strict stay-at-home order of about three months, and an aggressive vaccination program. Nevertheless, cases declined much more during similar lockdowns in March and April.

In continental Europe, a wave of B.1.1.7 cases had been forming for months, mostly under a steady churn of infection that went unnoticed. The variant wave is now cresting.

Poland’s daily new cases rate has risen from mid-February to the end of February after forcing most public places to close. Germany has doubled by banning night ceremonies in Berlin.

In France, where B.1.1.7 is causing Three quarters of new infection, Some hospitals had to go to coronovirus patients Belgium To empty the beds. Roughly as many people have been dying every day since Kovid-19 in Europe, this was the time of the year before.

For too long, government officials ignored the threat. “Case Platius can hide the emergence of new variants,” said Carl Pearson, a research fellow at the London Case of Hygiene and Tropical Medicine. “And the higher those plateaus, the worse the problem.”

In the United States, coronovirus infections began a rapid decline in January, soon prompting many state leaders to reopen businesses and ease restrictions. But scientists repeatedly Warned that the drop will not last. After nearly 55,000 cases per day and 1,500 deaths in mid-March, some states – notably Michigan – saw an uproar.

Since then, the national number has grown rapidly. until Saturday, The daily count was up to about 69,000, And the weekly average was 19 percent higher than the figure two weeks earlier.

Even when cases were falling, researchers questioned the notion of what the cause of the vaccination was. Millions of Americans are vaccinated every day, but still only 31 percent have received a single dose of a vaccine, and only 17 percent of the population receive full protection, leaving a vast majority susceptible.

“The fact that we’re still in a situation where we don’t have enough vaccinated people,” said Christian Anderson, a virologist at Scripps Research, San Diego. “And if we, like Texas, say we’re done with Kovid-19, B.1.1.7 will come in and remind us that we’re not right. I have no doubt about that.”

The variant is particularly widespread in Florida, where the state lifted the ban and did not initially see an increase. Officials in other states cited it as justification for reopening. But now Florida’s infection rate is declining upward.

The variant has only been favored by scientists to call the season. Respiratory infections are typically rare in the spring in Florida, noted Sarah Kobe, an evolutionary biologist at the University of Chicago. Coronovirus infection reached a peak in Florida last year, as heat drove people out of the house, and it may happen again.

“I still don’t think we’re out of the woods,” Dr. Kobe said, referring to the country at large. “If we don’t have another wave this spring, I’m really going to be, really worried about the fall.”

While most vaccines are effective against B.1.1.7, researchers are concerned about other variants that contain a mutation called E484K. (Scientists often refer to it appropriately, as “Eq.”)

This mutation has evolved independently in several variants worldwide, suggesting that it confers a powerful survival benefit to the virus.

In laboratory studies, Pfizer-bioentech And modern vaccines B.1.351 seem to be slightly less effective than the variants identified in South Africa. That variant contains eq mutations, which enable the virus to partially circumvent the body’s immune response. Vaccines made by Johnson and johnson, AstraZeneca And Novaxax Were also less powerful than B.1.351.

“I think for the next year or two, the E484K mutation will be the most”, said evolutionary biologist Jessie Bloom of the Fred Hutchinson Cancer Research Center in Seattle.

The mutation makes the so-called spike protein sit on the surface of the coronavirus, making it slightly harder for the antibodies to latch and destroy.

The good news is that the virus feels that there are only a few survivors in its bag, and this makes it easier for scientists to find and block their defenses. “I’m feeling great about the fact that there aren’t a lot of options,” said Michelle Nusenzweig, an immunologist at Rockefeller University in New York.

Eq mutations appear to be the primary defense of the virus against the immune system. Researchers in South Africa recently reported that a new vaccine directed against B.1.351 should be discontinued, along with all other variants.

Pfizer, Bayonet and Moderna are already testing newly designed booster shots against B.1.351 which should work against any variant known to blunt the immune response.

Instead of a new vaccine against the variant, however, it may be effective for Americans because a third dose of the Pfizer-BioNotech or Morden vaccine should be received for up to six months in a year, National Head Dr. Anthony S. Fauci said. Institute of Allergy and Infectious Diseases.

Antibody levels in each recipient will remain high, overwhelming any variant – a more practical strategy that emerges than creating a particular vaccine for each new variant, he said.

“My only concern about chasing all the variants is that you’ll almost be playing Whac-A-Mole, you know, because they’ll keep coming up and coming up,” Dr. Fauci said.

In one form or another, new coronoviruses are here to stay, many scientists believe. Multiple variants may prevail in the country at the same time, as in the case of the common cold coronavir and influenza. Keeping them at bay may require an annual shot like a flu vaccine.

The best way to prevent the emergence of dangerous adaptations is to keep matters low now and land most parts of the world, not just for the United States – as soon as possible. If significant pockets of the globe remain unprotected, the virus will continue to develop in dangerous new ways.

“This could be something we have to deal with for a long time,” said epidemiologist Rosalind Agogo of the London School of Hygiene and Tropical Medicine.

Still, she said, “even if it changes again, which it is very likely to do, we are in a better, better position than we were a year ago to deal with it.”

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