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Reports from Britain and South Africa of new strains of coronavirus that appear to spread more easily are alarming, but virus experts say it is not clear if this is the case or if they pose a problem for vaccines or cause more serious illness.
Viruses evolve naturally as they move through the population, some more than others. This is one of the reasons we need a new flu shot every year.
New variants, or strains, of the virus responsible for COVID-19 have been observed almost since it was first detected in China almost a year ago.
Prime Minister Boris Johnson on Saturday announced new restrictions due to the new strain, and several countries in the European Union have banned or restricted some flights from the UK in an attempt to limit any spread.
Here is what we know about the situation.
WHAT ABOUT THE RECENT STRAIN FOUND IN ENGLAND?
Health experts in the UK and US have said the strain appears to infect more easily than others, but there is no evidence, but it is more deadly.
Patrick Vallance, chief scientific adviser to the UK government, said the strain “is evolving rapidly and becoming the dominant variant”, causing more than 60% of infections in London in December.
The strain is also of concern because it has so many mutations – nearly two dozen – and some are on the spiky protein that the virus uses to attach itself and infect cells. This peak is the goal of current vaccines.
“I’m worried about that for sure,” but it’s too early to know how important this will be, said Dr Ravi Gupta, who studies viruses at the University of Cambridge in England. He and other researchers published a report on a website scientists use to quickly share developments, but the article has not been officially reviewed or published in a journal.
HOW DO THESE NEW STRAINS OCCUR?
Viruses often acquire small changes of a letter or two in their genetic alphabet just through normal evolution. A slightly modified strain may become the most common in a country or region simply because it is the strain that first settled there or because “super spreading” events helped it to settle there. root.
A bigger concern is when a virus mutates by altering proteins on its surface to help it escape drugs or the immune system.
“Emerging evidence” suggests this could start to happen with the novel coronavirus, wrote on Twitter Trevor Bedford, biologist and genetics expert at the Fred Hutchinson Cancer Research Center in Seattle. “We have now seen the emergence and spread of several variants” that suggest so, and some show resistance to antibody treatments, he noted.
WHAT OTHER STRAINS HAVE EMERGED?
In April, Swedish researchers discovered a virus with two genetic changes that appeared to make it about twice as infectious, Gupta said. Around 6,000 cases worldwide have been reported, mostly in Denmark and England, he said.
Several variants of this strain have now appeared. Some have been reported in people who obtained them from mink farms in Denmark. A new South African strain has both of the changes seen before, plus a few more.
The one from the UK has both and more changes, including eight to the spike protein, Gupta said. This is called a “variant under investigation” because its importance is not yet known.
The strain was identified in the south-east of England in September and has been circulating in the region since then, a World Health Organization official told the BBC on Sunday.
WILL PEOPLE WHO HAVE COVID-19 FROM AN OLD STRAIN BE ABLE TO GET THE NEW? WILL HE DETERMINE THE VACCINES?
Probably not, former US Food and Drugs Commissioner Scott Gottlieb said on CBS’s “Face the Nation” on Sunday.
“Not likely,” Gupta agreed.
President-elect Joe Biden’s surgeon general candidate Vivek Murthy told NBC’s “Meet the Press” Sunday that there was “no reason to believe that the vaccines that have been developed will not be equally effective against this virus. “
The vaccines produce a wide range of immune system responses beyond those to the spike protein, several experts noted.
The possibility that new strains will be resistant to existing vaccines is low, but not “nonexistent,” Dr Moncef Slaoui, chief scientific adviser for the US government’s vaccine distribution effort, said on Sunday on “The state of the Union ”from CNN.
“So far, I don’t think there has been a single variant that would be resistant,” he said. “This particular variant in the UK, I think, is very unlikely to have escaped vaccine immunity.”
Bedford agreed.
“I’m not worried” because a lot of changes in the genetic code would likely be needed to undermine a vaccine, not just one or two mutations, Bedford wrote on Twitter. But vaccines may need to be fine-tuned over time as the changes accumulate, and the changes should be monitored more closely, he wrote.
Murthy said the new strain did not alter public health advice on wearing masks, washing hands and maintaining social distancing.
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Associated Press editors John Hanna in Topeka, Kansas, and Sylvia Hui in London contributed reporting.
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The Associated Press’s Department of Health and Science receives support from the Department of Science Education at the Howard Hughes Medical Institute. The AP is solely responsible for all content.
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