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Coronavirus variants threaten to cause an epidemic, scientists say

For weeks, the mood in most of the United States has risen. Cases, hospitalizations և Mortality from coronavirus has dropped dramatically, և Millions of people are being vaccinated every day. Restaurants, shops and schools have reopened. Some states, such as Texas and Florida, have dropped the warning altogether.

Americans win the war on coronavirus by measurable means. Powerful vaccines և spread quickly, but guarantee the final return to normal: barbecues in the yard, summer camps և sleep.

But it is becoming increasingly clear that the next few months will be painful. The so-called variants are spread by carrying mutations that make the coronavirus “more contagious” and in some cases more deadly.

Even if the vaccines were allowed late last year, illuminating the road to an end to the epidemic, the options worried Britain, South Africa and Brazil. New versions continue to appear. One week in California, the next day in New York և Oregon. These new versions of the coronavirus, when rooted, threaten to delay the end of the epidemic.

At the moment, most vaccines seem to be effective against the variants. But public health officials are deeply concerned that further recurrences of the virus may be more resistant to the immune response, urging Americans to stand in line for booster shots or even new rounds of new vaccines.

“There is no evolution on our part,” said Devi Sridrar, a professor of public health at the University of Edinburgh in Scotland. “This pathogen always seems to change in a way that makes it difficult to suppress.”

Health officials recognize the urgent need to reverse these new viruses when crawling in the United States. Already, B.1.1.7, the highly contagious version that has swept Britain and wreaked havoc in continental Europe, is growing exponentially in the United States.

A limited genetic test found more than 12,500 cases, many in Florida and Michigan. As of March 13, the hypothesis in the whole country was about 27% of new cases, instead of only 1% at the beginning of February.

The Biden administration has pledged a $ 200 million “advance payment” to increase control, which it plans to inject so that it can analyze 25,000 patient samples for virus versions each week. It is an ambitious goal. The country collected only a few hundred samples each week in December, and as of March 27, it was collecting about 9,000 samples per week.

Researchers say that until recently, the increase in B.1.1.7 was masked by a slowdown in the overall rate of infection, giving Americans a false sense of security, leading to premature quiet restrictions.

“The best way to think about other variants of B.1.1.7 is to treat them as separate epidemics,” said Sebastian Funk, Professor of Infectious Diseases Dynamics at the London School of Hygienic Medicine. “We’re really kind of obscuring the point of view, adding all of them to give a total number of cases.”

Other versions found in South Africa և Brazil, as well as some versions of viruses first seen in the United States, are spreading more slowly. But they are also a concern because they contain a mutation that reduces the effectiveness of vaccines. The P.1 outbreak of the crushed version of Brazil a few days ago forced the shutdown of the Whistler Blackcomb ski resort in British Columbia, Canada.

Scientists say that the world has found itself in a sprint between “versions” of vaccines, and eventually the staff will win. But as each infection allows the coronavirus to develop further, vaccinations elsewhere in the United States should be given as soon as possible.

Infections are on the rise again, driven indefinitely by other variants of B.1.1.7. Last week, Dr. Rochelle Valensky, director of the Centers for Disease Control and Prevention, called on Americans to continue to pursue disguise and social exclusion, saying he felt a sense of “imminent judgment.”

“We have so much to look forward to, so many promises, so much potential, so much hope,” he said. “But right now I’m scared.”

“More contagious for more days”

The coronavirus was thought to change the egg slowly. Like all viruses, it can cause mutations to evolve into thousands of variants, scientists said at the beginning of the epidemic. But for years it would not change significantly. Stupid virus, some called it.

The pathogen refuted those predictions. “We expected the virus to change,” said Dr. Michael Diamond, a viral immunologist at St. Louis University in Washington. “We did not predict how fast it would happen.”

The option only worries if it is more contagious, causes more serious illness or weakens the immune response. Versions found in the UK, South Africa, Brazil և California all meet the criteria.

According to recent estimates, the first that has received widespread attention is B.1.1.7, which is about 60% more contagious և 67% more deadly than the original virus.

The version does not differ from the original, but infected people seem to carry more viruses for a longer period of time, says Katrina Litgo, an evolutionary biologist at Oxford University. “You are more contagious for more days,” he said.

B.1.1.7 is so contagious that Britain only managed to catch the infections after almost three months of strict home stays, plus an aggressive vaccination program. Even so, owning one is still beyond the reach of the average person.

In continental Europe, a wave of B.1.1.7 cases has been going on for months, mostly unnoticed, under a steady stream of infections. The optional channel is now being aired.

The level of new daily incidents in Poland has increased fivefold since mid-February, forcing most public places to close. Germany has doubled its ban on night rallies in Berlin.

In France, where B.1.1.7 causes three-quarters of new infections, some hospitals have had to transport coronavirus patients to Belgium to make beds available. In Europe, COVID-19 kills about as many people every day as it did this year a year ago.

For a long time, government officials ignored the threat. “Caseplates can hide the emergence of new options,” said Carl Pearson, a researcher at the London School of Hygiene and Retrospective Medicine. “And the higher those plateaus, the worse the problem.”

Coronavirus infections in the United States began to decline rapidly in January, which soon prompted many heads of state to reopen their businesses and ease restrictions. But scientists have repeatedly warned that the decline will not last. After the rate reached about 55,000 deaths in mid-March 1500 1,500 deaths a day, some states, particularly Michigan, began to rise.

Since then, the national number has been growing steadily. The daily estimate for the week was almost 69,000, and the weekly average was 19% higher than two weeks ago.

Even as cases approached, researchers questioned the idea that vaccines were the cause. Millions of Americans are vaccinated every day, but even now only 31% have received a single dose of the vaccine, and only 17% of the population has full protection, leaving the vast majority vulnerable.

“The fact is, we don’t have enough vaccinated people right now,” said Christian Andersen, a virus specialist at Scripps Research in San Diego. “And if we, like Texas, say we’re done with COVID-19, B.1.1.7 will come in and remind us that we’re not right. I have no doubt about that. “

The option is especially popular in Florida, where the state lifted the restrictions and did not initially see a wave. Officials in other states saw this as a reason for reopening. But now Florida’s infection rate is rising.

The option can be hidden only due to what scientists like to call seasonality. Respiratory infections in Florida are usually rare in the spring, says Sarah Kobe, an evolutionary biologist at the University of Chicago. The peak of coronavirus infections in Florida was last summer, as the heat was taking people home – it could happen again.

“I do not think we are out of the woods yet,” Cobb said of the country as a whole. “If we do not have another wave this spring, I will be really, really worried about autumn.”

Although most vaccines are effective against B.1.1.7, researchers are increasingly concerned about other variants that contain a mutation called E484K. (Scientists often call it “Eek”).

This mutation has evolved on its own in many parts of the world, suggesting that it offers the virus a powerful survival advantage.

In laboratory studies, the Pfizer-BioNTech և Moderna vaccine appears to be slightly less effective against B.1.351 variant found in South Africa. This version contains an Eek mutation that appears to allow the virus to partially bypass the body’s immune response. Vaccines made by Johnson & Johnson, AstraZeneca և Novavax were even less potent against B.1.351.

“I think E484K is going to be the most troubling mutation in the next year or two,” said Essie Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Research Center in Seattle.

The mutation slightly alters the so-called spike protein that sits on the surface of the coronavirus, making it a little harder to kill the antibody-blocking antibody.

The good news is that there seem to be a few tricks to the virus in the virus bag, making it easier for scientists to find and protect those defenses. “I feel pretty good about the fact that there are not so many choices,” said Michel Nussenweg, an immunologist at Rockefeller University in New York.

The Eek mutation appears to be the primary defense of the virus against the immune system. Researchers in South Africa recently reported that a new vaccine against B.1.351 should also be avoided.

Pfizer, BioNTech և Moderna are already testing newly developed booster shots against B.1.351, which should work against any known variant to suppress the immune response.

However, instead of a new version of the vaccine, it could be just as effective for Americans to get a third dose of Pfizer-BioNTech or Moderna vaccine in six months to a year, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

It raises the level of antibodies in each recipient, suppressing any option. “It’s a more practical strategy than making a specific vaccine for each new version,” he said.

“My only concern with pursuing all the options is that you will almost play a mole, you know, because they are constantly rising, they keep coming up,” Faucin said.

Many scientists believe that the new coronavirus will remain here in one way or another. Many variants can be circulated in the country at the same time, as is the case with common cold coronaviruses: flu. Keeping them away may require an annual shot, such as a flu shot.

The best way to curb the emergence of dangerous options is to close the case now և vaccinate as soon as possible not only the vast majority of the United States in the world. If significant pockets of the planet are left unprotected, the virus will continue to develop dangerous new eggs.

“This could be something we have to deal with for a long time,” said Rosalind Ego, a public health researcher at the London School of Hygiene and Retrospective Medicine.

Still, he added. “Even if it changes again, which it will probably do, we are in a better, much stronger position than a year ago to do it.”


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