NEWS | February 12, 2021

COVID-19 variants: More contagious and deadly – but masks and distancing still work

Time to “double down” on coronavirus precautions to protect yourself and others


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There is bad news and good news about the COVID-19 variants emerging around the world and in California. 

The bad news: Studies show three major variants, the ones first found in the UK, South Africa and Brazil, are more infectious, cause more serious cases of COVID-19 and increase the risk of dying. 

And Bart Weimer, a population health professor in the UC Davis School of Veterinary Medicine, said on UC Davis LIVE that he has little doubt the more serious variants are spreading throughout the state and the U.S. (Cases have been found in Northern California, including in Davis.) 


Wearing masks, social distancing, meeting people outdoors work just as well to protect you from the new COVID-19 variants

The good news: Wearing a face mask, keeping a 6-foot social distance and sticking with the other precautions that have worked well against COVID-19 will be just as effective against the new variants. 

“Everything we’ve been doing still works,” Dean Blumberg, chief of pediatric infectious diseases at UC Davis Children’s Hospital, said on the broadcast. “Being outdoors if you’re around other people, social distancing and proper masking work the same on all the variants. They are just a reason to double down on those.” 

Just as importantly, Blumberg said, it appears – although data is still being gathered – that the current vaccines will be helpful against the variants, even if they lose some effectiveness. 

“We still don’t have specific numbers, but the two U.S.-approved vaccines (from Pfizer/BioNTech and Moderna) are about 95% effective against most variants of SARS-CoV-2,” he said. “So, maybe with the new variants they will be 85% effective. Maybe they won’t prevent all mild cases of COVID-19, but they’ll prevent serious disease and hospitalization. There will be some protection.” 

For comparison, flu vaccines average about 40% effectiveness. 

“The COVID-19 vaccines create an immune response to several areas of the spike protein. The mutation (in the variants) is to just one area of the spike protein,” Blumberg said. “That 95% protection is very good. If it’s only 85%, I’ll take that, it’s still really good.” 

Read about vaccine myths vs. facts 

How the coronavirus makes variants

It helps to understand the nature of the coronavirus variants. All viruses mutate constantly, Weimer said, including this one. The reason: this coronavirus is bad at copying its genome when it multiplies in our bodies, which it does millions of times in someone who’s infected. 

“This virus is very good at being able to make its changes very quickly,” Weimer said. “Some of those changes are its increased ability to transmit to another person. The changes will get passed along locally and by people travelling around.”

— Bart Weimer

Those millions of replications create many, many new viruses with tiny changes. The vast majority have no effect on the nature of the virus, or they don’t survive because they weaken it. The few changes that do last, live on because they give the virus a survival edge – they help it multiply faster, or spread through a population, or make it resistant to a body’s defenses, like antibodies. 

“This virus is very good at being able to make its changes very quickly,” Weimer said. “Some of those changes are its increased ability to transmit to another person. The changes will get passed along locally and by people travelling around.” 

How the variants are different

The variant first found in the UK strain is known as B.1.1.7. The variant discovered in South Africa is 501Y.V2. The variant found in Brazil is P.1. 

“The UK variant has some mutations that allow it to bind more tightly to our cells and it enters the cell more rapidly,” Blumberg said. “This results in a higher concentration of virus.” 

All those qualities make the variant about 50% more transmissible, according to the latest studies. It also causes more severe illness. 

“If you have a higher concentration of virus, you’re likely to get sicker,” Blumberg said. “The latest information, mostly from the UK, says B.1.1.7 results in a 65% increased risk of death.” 

The variants first found in South African and Brazil are similar, he said. They’re based on the B.1.1.7 variant, so are more transmissible. They also have another mutation that appears to escape some of the immune response induced by previously having COVID-19 or by the vaccine. 

The road ahead with COVID-19 variants

What that means, Blumberg and Weimer said, is that it’s possible we could be getting annual COVID-19 shots the way we get yearly flu vaccines. 

“One of the good things about the current vaccines, is that they are really easy for vaccine manufacturers to update,” Blumberg said. “They know which spike protein will be the model for the new vaccine. It’s much easier than updating for the flu. They can do it in a weekend.” 

“If you detect it once, you have to imagine it’s spread more widely in the population. Whether that means 10 times more cases or 10,000 times more cases, we just don’t know.”

— Dean Blumberg

New vaccines or boosters would still need to go through full clinical trials and studies, so the total time required would be a few months. 

One of the issues with COVID-19 variants is that the U.S. has only begun genome sequencing, unlike countries such as the UK that sequence vast numbers of positive COVID-19 tests. This is one reason that variant was discovered first there. 

“If you don’t look for it, you can’t find it,” Blumberg said. “So, if you detect it once, you have to imagine it’s spread more widely in the population. Whether that means 10 times more cases or 10,000 times more cases, we just don’t know.” 

The positive news is that the U.S. efforts are both spreading and becoming better organized, Weimer said. “I think the U.S. is on the right road,” he said. 

Given the evolving nature of the science and the lingering uncertainties, how should we think about the variants? 

“I think things are going to get better,” Blumberg said. “We have two vaccines available now and three more that we expect to be available in the coming months. That’s why it’s so important that everyone get vaccinated. The fewer the people who get the disease, the fewer the opportunities for the virus to keep mutating.” 

That’s also why masking, social distancing and more are so crucial. They also cut down on the chances for the virus to mutate. 

“Stay diligent,” Weimer said. “We may be able to loosen things up in a few months, but we know the variants are in the U.S. They are coming our way, so don’t give up on the protections.” 

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