What Does the More Contagious Strain of Coronavirus in Washington State Mean, and What Can Be Done?

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It was only a matter of time until a new, possibly more contagious, variant of SARS-CoV-2 showed up in Washington state.

The newer coronavirus strain, which was first identified in September in the United Kingdom, has been confirmed in two people in Snohomish County and one in Pierce County.

The variant found in Snohomish County was detected through local public health case and contact tracing and genome sequencing at the UW Medicine Clinical Virology Lab.

What does it mean for the pandemic in Washington now that the strain is present? How can people protect themselves and those around them from catching and spreading the more contagious variant known as B.1.1.7? Should people double up on masks?

We address those questions in this week's installment of FAQ Friday.

What is the new coronavirus variant and why is it more contagious?

The B.1.1.7 variant has been found in 24 states, including Washington, and has become the dominant strain in the U.K.

The emergence of the strain isn't a surprise because viruses are always changing, looking for a more secure toehold in our cells.

"We've reached a point one year on and in certain parts of the world where the density of natural immunity is sufficient so that the variants that have got a fitness advantage ... are more likely to emerge and spread," Wendy Barclay, the head of infectious diseases at Imperial College London, told Stat News.

A single mutation rarely makes major changes to the virus. When a number of mutations happen, a new variant of the virus occurs, which can make the virus more transmissible and more dangerous, but not always.

The variant identified in Pierce and Snohomish counties appears to be more transmissible than most other strains. Public health officials believe it could become the dominant strain later this year.

When a variant of a virus such as B.1.1.7 emerges and takes root, as it did in the U.K., it is partly because a number of mutations gave it an advantage. The B.1.1.7 variant has a mutation to one of the spike proteins that better allows it to attach to and invade its host's cells.

Scientists are still studying the variant but it doesn't appear to cause more severe infections, unlike earlier coronaviruses SARS and MERS, which were not as contagious but caused much harsher infections.

While the B.1.1.7 variant is worrisome, Dr. Wes Van Voorhis, director for emerging and reemerging infectious diseases at the University of Washington School of Medicine, is more concerned about a variant identified in South Africa.

Early reports about that variant, B.1.351, show that people have been reinfected by the variant and plasma taken from recovered people hasn't neutralized the new variant, Van Voorhis said.

The B.1.351 strain has infected two people in South Carolina, state officials announced Thursday. Neither had traveled recently.

Another variant that was first identified in Brazil shares a mutation — called E484K — with the variant from South Africa, which could help the virus hide from neutralizing antibodies. The Brazilian variant, P.1, was detected in a resident of Minnesota who had traveled to Brazil.

The E484K mutation has shown up in the U.S. but hasn't led to major outbreaks, Trevor Bedford, a computational biologist at the Fred Hutchinson Cancer Research Center who has been tracking genetic changes in the virus since the start of the pandemic, told The Seattle Times a couple of weeks ago.

"It appears that just having the (E484K) mutation isn't enough to make a huge difference to the virus," he wrote in an email. However, in combination with the 10 or more other mutations in the South Africa and Brazil variants, it is spreading rapidly.

So far, it appears the various variants aren't different enough to completely evade the effects of the coronavirus vaccines, Van Voorhis said.

"It's not an issue yet, but it's something we're all closely following," he said.

What can be done to better protect against new coronavirus variants?

Public health officials and doctors are urging people to continue doing what has been done so far to curb the spread of the coronavirus and the disease it causes, COVID-19: Practice good hand hygiene, continue social distancing and wear face coverings.

Wearing masks properly and having multiple layers can help protect the wearer and those around them, said Dr. Jeff Duchin, health officer at Public Health — Seattle & King County.

"Two or three layers of fabric and a snug fit are very important, along with using the mask consistently whenever around others outside the home," Duchin wrote in an email. "If air leaks out around the sides or your glasses fog up, or if it's not worn reliably, it's not going to be very effective. I think layering two cloth masks on one another or on top of a surgical mask to improve filtration and fit are reasonable strategies to improve protection."

Double-masking "likely does" help protect against the variant strains and, "it just makes common sense that it would be more effective," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told the "Today" show on Monday.

Beyond tried and true preventive measures, people need to get vaccinated once they can, Van Voorhis said.

"Bottom line is, get vaccinated early, and it'll probably help against all these variants," he said.

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