CDC predicts highly contagious coronavirus mutants to spread to the United States

The cases are mostly separated. One in New York, one in Florida, one in Georgia, two Colorado..The exception is California, especially San Diego County, where strong surveillance activities have been discovered. 32 cases of variants.. Francis Collins, director of the National Institutes of Health, told The Washington Post on Wednesday: “I would be surprised if it didn’t grow that fast.”

There is no evidence that a recently detected variant was detected in Over 30 countries, Increases the risk of serious illness and death. However, the emergence of coronavirus variants, including mutants containing other mutations that occurred in South Africa, poses a challenge for all countries wishing to shatter the pandemic.

The more contagious virus can drive more patients to hospitals and increase the number of deaths from covid-19. It can also prolong the march to herd immunity. It is the point at which pathogens circulating in the population hit so many immunized people that any outbreak quickly disappears and becomes non-epidemic. The proportion of people who need immunity to the population to achieve herd immunity is higher for more infectious pathogens.

Variant growth can also limit the effectiveness of Monoclonal antibody treatment Such treatments are very narrow-focused and can be avoided by a single mutation.

The effects on the vaccine are ambiguous in the long run. Coronavirus It keeps changing.But the consensus is that it is newly approved Vaccine Probability is high Maintain effect Against previously seen mutants to elicit a variety of neutralizing antibodies and other immune system responses. In addition, Pfizer / BioNTech and Moderna mRNA (messenger RNA) vaccines can be easily adjusted for mutations as needed.

All of these claim to strengthen surveillance of the virus as it spreads throughout the population and clashes with innate and vaccine-induced immunity. The virus is not static and the mutations are random, but natural selection produces mutants that infect humans and have a high ability to replicate. A Research Published by scientists at Imperial College London last week and not yet peer-reviewed, the first variant detected in the UK is estimated to be 50% more contagious than the more common virus strains. I will.

“Here at the CDC, we definitely take this seriously, and for now we assume that this variant is more contagious,” said Greg Armstrong, leader of the CDC’s strain monitoring program. I am. The UK variant “probably not in all states at this time, but I think it is in many states.”

Experts say this increases the urgency of vaccination of as many people as possible, and some respected scientists mean that it cuts the dose in half or delays the second. Even as he argued that the protocol for distributing 2-dose vaccines needed to be modified to inoculate more people. This week’s Food and Drug Administration said it would stick to two-shot doses backed by randomized clinical trials.

All viruses mutated, In addition, the new coronavirus SARS-C0V-2 does not mutate rapidly or in an abnormal manner. However, with tens of millions of people infected worldwide, the virus has plenty of opportunities to change shape randomly, and natural selection does the rest, giving the virus the ability to evade innate or vaccine-induced immunity. There is a possibility.

“We are in the fight against time,” said Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Health and Security Center. “We need to speed up our actions so that the virus doesn’t spread further and that this variant becomes dominant in the distribution. The clock is ticking.”

The United States is lagging behind in developing genomic sequencing that will allow the United Kingdom to closely monitor viral mutations and the spread of various variants. The CDC established a consortium last spring to collect data on genomic sequences and created a new program for strain monitoring in November.

In an interview, Armstrong said the agency and its contract partners hope to more than double the number of genomic sequences posted on public websites in the next two weeks.

“We haven’t done enough sequencing yet. We need to keep building what we’re doing,” Armstrong said.

He said South African variants have not been detected in the United States.But the British variant may have been here After october, According to preliminary data from the private coronavirus test. The data is not completely conclusive as it is not based on comprehensive genomic sequencing.

Instead, British variants lack some of the genetic code found in common coronaviruses. Coincidentally, the commonly used Thermo Fisher PCR test can detect the dropped gene with a positive test result. Without the complete genomic sequence, it is not possible to know if the dropout is actually a signal for the UK mutant, as other unrelated mutants also have the missing gene.

However, according to Armstrong, among the positive results detected in the PCR test, the dropout signal increased from .25% to .5% in a few months. In the UK, the same pattern was maintained. After a very modest increase in the prevalence of variants, it suddenly surged and became the dominant strain in southern England, leading to a new series of blockades.

According to a study by Imperial College, this mutant first appeared in genomic sequences acquired by British scientists in late summer or early autumn. However, it was officially identified as a “variant of concern” in early December and was announced to the British people and other countries on December 14.

According to Armstrong, CDC officials quickly assumed that the CDC already existed in the United States due to the high volume of travel between countries. The CDC says it expects the percentage to increase in all cases. “Assuming the data seen in the UK is correct, we are 50% more likely to send. We may see this increase in the coming months.”

There is no evidence that this variant is causing the fall / winter surge in the United States. If so, it would have appeared in more genomic sequences analyzed by researchers in the last few weeks.

This variant, called B.1.1.7, has 17 mutations, including eight that affect the structure of peplomer proteins protruding from the surface of the virus. The exact outcome of each mutation is unknown, but genetic alterations appear to make it easier for the virus to bind to human receptor cells and increase the viral load in infected individuals.

Its high viral load may not mean a more serious illness, but it will probably lead to a larger infection as it releases more virus each time people cough or sneeze.

“The data are really worrisome. All current signs show the fact that this is something we should worry about,” said Mary Caslingla, an infectious disease epidemiologist at the Johns Hopkins Bloomberg School of Public Health. Bowski says.

Even a seemingly slight increase in transmission rate “can mean a huge number of cases,” she said.

The spread of variants can impose new restrictions on civil servants and delay scheduled resumptions.

“if [the variant] Columbia University epidemiologist Jeffrey Shaman said he began taking over to be more aggressive and that measures that didn’t work very well at first would reduce the virus’s control.

More contagious variants of the coronavirus may have had disproportionate effects on people under the age of 20, according to a study by Imperial College. According to the authors of the study, this may have been a social cause rather than a biological cause. The school was open, but the rest of the country was observed when it was closed.

The authors of the study analyzed genomic and epidemiological data collected in the United Kingdom from early November to December. By measuring so-called replication numbers (aggregates of other people infected with the virus-infected individual), scientists have found that this mutant has a “substantial infection advantage” compared to other strains. I concluded.

In the United States, school superintendents and boards of education are monitoring infection rates in communities involving the new covid-19 strain, and are the secretary-general of the Great City Schools Council, the largest non-profit organization representing cities. Said Michael Casserly. Country school district.

“As our superintendent and board monitor community infection rates from this new strain, accurate opening dates in many of our metropolitan school districts remain in flux,” he said. Told.

Bob Lancy, director of education at Broward County Public School in Florida, said the school was reopened on Monday for students who wanted to attend in person.

“Given the data we have and in consultation with public health authorities and medical professionals, our school is relatively not a site of serious infection with the coronavirus. It’s safe, “said Lancy.

Valerie Strauss contributed to this report.