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cutaway view of COVID virus with RNA inside

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Viruses mutate; so does everything, really. But experts are now concerned about a few of the thousands of coronavirus variants that have turned up around the world. We wrote about the UK variant last month; now there are more, including one in Los Angeles. You do not need to panic. But it’s good to be informed.

One of the big reasons we’re seeing new variants now, a year into the pandemic, is that there’s just so much more virus out there than there was 12 months ago. The more virus there is in the world, the more chances it has to mutate. And the more variants there are, the greater the chances that some of them will be bad news.

If we (as a global community) had done a better job of containing the virus in the first place, we might not have gotten to the point where there are multiple variants that are different enough to worry the experts. But here we are.

Another thing to remember is that you’ll only find variants if you’re looking for them. The UK variant, B.1.1.7, was discovered in part because the UK does a lot of what’s called surveillance testing—monitoring exactly what kinds of coronaviruses are out there. The U.S. does some of this too, but much less. The B.1.1.7 variant was probably already in other countries by the time it was discovered in the UK; they just hadn’t found it yet.

What are the variants to know?

B.1.1.7 was found in November 2020 in the UK, where it had probably been circulating since September or earlier. This New York Times article has more details on the strain and its mutations. It seems to be 50% more transmissible than a typical COVID virus. It has multiple mutations, including eight on the spike protein.

(The spike protein is the part of the virus that interacts with our cells. When we make antibodies to the spike protein, those antibodies can stop the virus from infecting us. The mRNA vaccines include the genetic code of the spike protein, which allows our cells to make the protein and then make antibodies to it.)

B.1.1.7 is more transmissible, but the disease it causes does not seem to be any worse than usual.

B.1.351 was discovered in South Africa, in samples dating back to October 2020, and it also has mutations in the spike protein. It seems to be more transmissible than typical COVID, but does not change the severity of disease. Both this variant and the one from the UK share a mutation called N501Y. A recent study, posted as a preprint, found that the Pfizer vaccine does seem to protect against variants with this mutation.

P.1 is a variant from Brazil, first detected in December 2020. It also has mutations that seem concerning, including to the spike protein. One of its mutations, E484K, may be able to evade antibodies; there’s some reason to suspect that people who have recovered from a previous case of COVID can be infected by these mutations.

CAL.20C is a variant that’s becoming popular in Los Angeles. We don’t know much about it yet.

For all of these variants, the science is still very new. The things we know about them are tentative. None of them seems to cause more severe disease; most are probably susceptible to the existing vaccines; and PCR tests still seem to be able to detect them.

They have also often become the dominant strains in their locations, but for some of the variants, there’s a bit of a chicken-and-egg problem in determining whether they are responsible for spikes in cases or not.

What happens now?

Two things. First, scientists are working on answering the unanswered questions about these variants.

For example, we need to find out whether they’re truly more transmissible, and if so, by how much. We need to know if the variants can evade our natural immunity (which would mean you could catch the virus twice) and whether they can evade immunity from the various vaccines and vaccine candidates that already exist. We need to know if any of the variants cause more severe disease or if there are any clinical differences. And we need to amp up our surveillance, in every country, to be able to find new variants as they emerge and watch where existing variants are taking over.

In time, if it turns out that new variants can evade existing vaccines, the vaccines may need to be updated. We do this for the flu vaccine every year; it’s possible we may have to do the same thing for the COVID vaccine.

But the other action item is simpler, if still difficult: We need to do all the same things we’ve been doing for prevention, only to a greater degree. If a variant is more transmissible, it’s even more important to wear masks and stay home and take testing seriously. It’s extra, extra important to get vaccines to people as quickly as possible. So in that sense, even if the virus changes, our most important measures for controlling it have not changed.



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