New COVID strain in UK may be more contagious, officials say. Here’s what to know

Word of a more contagious coronavirus strain circulating overseas has reached the U.S. after officials in the United Kingdom announced on Sunday new travel restrictions and lockdown measures.

The new variant appears to spread more easily between people and may be up to 70% more transmissible than other existing coronavirus strains, U.K. Prime Minister Boris Johnson said during a Saturday press conference, according to CNN.

However, scientists say there’s no evidence the new variant is more deadly or resistant to COVID-19 vaccines.

What’s more, estimates of greater transmissibility are based on modeling, not lab experiments, Dr. Muge Cevik, an infectious disease expert at the University of St. Andrews in Scotland and a scientific adviser to the British government, told The New York Times.

It’s a finding that’s worrying, but not surprising, experts say, and one that could explain the recent surge of COVID-19 cases in the U.K.

“Of course we should all be concerned about the emergence of a new and distinct variant of SARS-CoV-2. However, it is important to point out that it is still the same virus, causing the same disease,” Mark Harris, a virology professor at the University of Leeds in England, said in a statement.

“The mechanism by which it is transmitted is also the same, but the genetic changes in this variant appear to enable it to transmit more efficiently, although the biological explanation for this increased rate of transmission remains to be determined,” Harris added.

The new variant was first identified in England on Sept. 20, accounting for about 26% of all cases by mid-November in the area, according to U.K. chief science advisor Patrick Vallance, Science Magazine reported. “By the week commencing the 9th of December, these figures were much higher. So, in London, over 60% of all the cases were the new variant.”

The new strain has been identified in Denmark, the Netherlands and Australia, according to NBC News.

A similar version that shares one of the mutations from the U.K. variant has emerged in South Africa, The New York Times reported. It has been found in up to 90% of the patient samples that have been genetically sequenced there since mid-November.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told CNN on Monday that the U.S. should “without a doubt keep an eye on it,” but at the same time “we don’t want to overreact.”

Although other countries have suspended travel in and out of the U.K., Fauci told the outlet he doesn’t suggest America do the same.

Why scientists are concerned about the new coronavirus strain

Scientists are concerned about the new strain because it developed 17 mutations at once, “a feat never seen before,” Science Magazine reported, eight of which are involved with the coronavirus’ spike protein — the molecule it uses to infect human cells.

Immune systems use these spiky proteins to remember the virus and create antibodies to fight them, but if they become unrecognizable, efforts to prevent the pathogen from attacking again may not work.

That’s why people need to get a flu shot every year.

“This virus mutates like all viruses. Flu mutates the most ... [changing] its surface proteins very rapidly. So, we constantly need to get a new flu shot. Some viruses like measles don’t change their surface proteins. And so the measles shot we got 20 years ago still works,” Dr. Scott Gottlieb, the former head of the U.S. Food and Drug Administration, told CBS News.

These minute changes in the coronavirus’ genome are normal and indeed happening all the time, but most are insignificant and don’t change how deadly or infectious it is.

In July, researchers discovered a different coronavirus strain in Europe that was brought to the U.S. and also appeared to be more contagious, but not more deadly in a lab setting, McClatchy News previously reported. Studies showed this mutated form of the virus was 10 times more infectious than the original version from Wuhan, China — where COVID-19 first emerged — because it had “four to five times” more spikes on the virus’ surface that allowed it to infect cells more easily.

The coronavirus in general has developed mutations “at a rate of about 1 to 2 changes per month,” according to Science Magazine, which means the virus today differs by about 20 “points” compared to the first genetic sequences from China in January.

Scientists think this new strain may have evolved within a single patient experiencing a long infection that gave the virus time to learn which changes it needed to continue spreading and thus surviving.

However, scientists don’t have enough evidence to confirm this hypothesis. Another explanation is that a superspreader event led to the massive spread of this one strain.

“You have to understand that the virus doesn’t want to kill us. It does not want to be deadly,” Dr. Andria Rusk, an assistant professor specializing in infectious disease at Florida International University’s College of Public Health and Social Work, told McClatchy News in July. “It wants for the human host to survive and be symptomatic for as long as possible because that perpetuates itself. The longer it’s able to keep us contagious, the better off the virus is.”

Surgeon General Dr. Jerome Adams told CBS News that officials “have no indications that it is going to hurt our ability to continue vaccinating people or that it is any more dangerous or deadly than the strains that are currently out there and that we know about.”

Dr. Moncef Slaoui, the chief science adviser for the U.S. government’s vaccine distribution effort, also says the chances the coronavirus will become resistant to the vaccines are low, but not “inexistent,” according to the Associated Press.

“Up to now, I don’t think there has been a single variant that would be resistant,” Slaoui told CNN, the AP reported. “This particular variant in the U.K., I think, is very unlikely to have escaped the vaccine immunity.”