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 United Kingdom, South Africa and Brazil, are more infectious, cause more serious cases of COVID-19 and increase the risk of dying.
Bart Weimer, a population health professor in the School of Veterinary Medicine, speaking on the Feb. 11 edition of UC Davis LIVE, said he had little doubt the more serious variants are spreading throughout the state and the United States. (Cases have been found in Northern California, including in Davis.)
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The good news: Wearing face masks, keeping physical distance of 6 feet from other people 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,” said Dean Blumberg, chief of pediatric infectious diseases at UC Davis Children’s Hospital, appearing on the same UC Davis LIVE. “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 important, Blumberg said, it appears the current vaccines — even if they lose some effectiveness against the variants — will still be helpful. He added that data is still being gathered.
“We still don’t have specific numbers, but the two U.S.-approved vaccines (from Pfizer-BioNTech and Moderna) are about 95 percent effective against most variants of SARS-CoV-2,” he said. “So, maybe with the new variants they will be 85 percent 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 percent 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 percent protection is very good. If it’s only 85 percent, I’ll take that — it’s still really good.”
All viruses mutate
It helps to understand the nature of the coronavirus variants. All viruses mutate constantly, Weimer said. This particular coronavirus is bad at copying its genome when multiplying in our bodies, which it does millions of times in someone who’s infected.
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. Of the few changes that do last, they 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 traveling around.”
How the variants are different
The variant first found in the U.K. 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 U.K. 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 percent 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 U.K., says B.1.1.7 results in a 65 percent increased risk of death.”
The variants first found in South Africa 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
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.”
- School of Veterinary Medicine Town Hall: Open to all, noon Wednesday, Feb. 17, on immune response to SARS-CoV-2, and viral variants and how they may influence public health response and vaccination strategies.
- More UC Davis LIVE: See our playlist that includes many other programs focusing on COVID-19.
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 United States only recently began genome sequencing, unlike places like the United Kingdom that have been sequencing vast numbers of positive COVID-19 tests. This is one reason B.1.1.7. was discovered there first.
“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 United States is 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, physical distancing and other protocols 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.”