Tuesday, July 27
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New coronavirus variants are spreading. Heres what to do and how much to worry. – Slate

Even as things look promising for summer, the coronavirus is still finding new ways to threaten our creep back to normal and our general sense of health and safety. Lately, it’s been the so-called South Africa, U.K., and Brazil variants, as well as newer variants like the ones that have popped up in New York City and California. It’s hard to keep track of them all and their whereabouts. The U.K. variant, which appears to spread easily, may become dominant in the U.S., the Centers for Disease Control and Prevention said Monday. On Tuesday, health officials announced they’d found the Brazil variant in Massachusetts. France’s health ministry just reported several cases of a new variant that may be harder to spot with tests.

You might have some questions about what this all means for vaccines, masks (and lack thereof), and our general future. I spoke to four experts, and here’s what they say we know—and what we’re still waiting to find out.

Why is the virus mutating?

Each time the SARS-CoV-2 virus infects a new person, “it has to copy itself,” says David Kennedy, a disease ecologist at the Penn State Center for Infectious Disease Dynamics. All these copies of the virus run around in your body, wreaking havoc and making you sick. With each new copy comes the chance to make mistakes in the duplication process. These mistakes are mutations. What each mutation means depends on the luck of the draw. Most mutations have no effect, make the virus worse at infecting people, or make it die right away. But some mutations make the virus better at infecting people. Those are the problematic ones.

OK, how do I know which variants to freak out about?

Well, for starters, things seem mostly fine now—more on why in a bit. But we just don’t know yet whether all the newest variants are concerning. Just like it was hard to tell how the then-new coronavirus was going to play out globally in January 2020, you can’t simply look at a variant and predict how it’s going to behave (and how people and governments are going to address it). But there are some things scientists look out for. The clearest sign that a variant is worrying is if it’s responsible for an increasingly large percentage of cases in a particular area, says Kennedy. That’s an indication that the variant is better at infecting people than the rest of the SARS-CoV-2 that’s out there right now. It means that natural selection is causing that particular variant to take over.

Increased transmission is another sign. Contact tracing can help researchers figure out if someone infected with a new variant is more likely to spread it around to others. Brianne Barker, a virologist at Drew University, says she began to be more concerned about the U.K. variant when contact tracing data showed that an infected person could spread it to more people than someone with the original SARS-CoV-2.

A third, less certain sign is whether the variant has one particular mutation. The South Africa, U.K., and Brazil variants have what scientists refer to as the “501 mutation.” This is a change in those little spiky things that cover the virus, one that makes it better at getting into human cells, says Scott Weaver, a virologist and scientific director of Galveston National Laboratory. “That one mutation appears to be responsible for most of the increased transmission,” Weaver says. But just having the 501 mutation isn’t enough to make a new variant concerning, says Kennedy. “These mutations don’t act by themselves,” he says. “Everything sort of interacts with everything else. So the same mutation on two different viruses could have very different effects.”

Which is to say: Figuring out whether a new variant is concerning is complicated, even if you happen to be equipped to examine its DNA. If you’re just scanning the news, it’s even harder to tell. If a story about a new variant doesn’t cite explicit evidence that it’s becoming more prevalent or more transmissible, it’s probably safe not to worry about it.

Well, what about variants that are increasing transmission, like the U.K. one?

Even concerning variants shouldn’t change your personal calculus that much, except to make sure you’re avoiding other people indoors and wearing effective masks. Those strategies do work against the variants.

Is it possible that there could be a variant that would really change our strategy—say, one that’s more transmissible on surfaces?

None of the current variants has been found to be better at surface transmission, says Weaver. Theoretically a variant could develop that was better at transmitting via surfaces. For example, it could be more stable and last longer on, say, a tabletop or doorknob. (But you should be washing your hands regularly now anyway.)

What is different about, say, the U.K. variant that makes it spread around more easily?

Right now, a few different things could give a variant increased transmission. It could reproduce more inside the nose and throat. More virus means more shedding—that is, escaping your body and potentially making it into other people’s bodies. Hamsters with the U.K. variant shed more virus, Weaver’s lab found. Or a variant might need less virus to establish an infection.

Are the vaccines less effective against the new variants?

We don’t know the full picture in detail yet, but what we do know is actually fairly encouraging. The experts I spoke with agreed that the vaccines will likely be effective for preventing a lot of the risk of severe and critical disease. The Johnson & Johnson vaccine was tested against the South Africa variant in its clinical trial. It was 64 percent effective in South Africa. While that’s less than its 72 percent effectiveness in the U.S., it still offers quite a bit of protection. Remember that before the vaccines were tested, the Food and Drug Administration was prepared to approve anything with more than 50 percent efficacy, and annual flu vaccines are 40–60 percent effective.

The variants didn’t exist yet during Pfizer’s and Moderna’s clinical trials. But Kennedy says “there’s really good reason to think that they’ll still have good efficacy against these variants,” and the other experts I talked to agree.

Wait, but it sounds like the Johnson & Johnson vaccine is less effective against the South Africa variant. Why the optimism?

What would be really bad is a variant that could evade vaccine-induced immunity entirely. The good news is that none of the current variants seems to do that. According to a couple of papers that have not yet been published, antibodies produced with help from the vaccines seem to effectively neutralize the U.K. variant, Weaver says. Manufacturers design a vaccine to help the body throw a bunch of different antibodies at the virus so that in combination they’ll all be enough to knock it out. Weaver says there is a “pretty consistent picture emerging” that the South Africa variant is probably a little bit nimbler against one antibody, “but there would be still quite a bit of protection” from the vaccine. Antibodies hamper the virus by glomming onto all those spikes that stick up from it. “The spike protein is huge, so there are going to be antibodies to many different portions of it,” says Barker. It would take a lot of mutations to make a variant that could dodge every one of those antibodies. Plus, the vaccines also nudge the body to produce T cells, and a recent preprint found that those T cells were still equally protective against the new variants. “Normally people think of it as something that’s binary, right? The vaccine works, or the vaccine doesn’t work,” says Kennedy. “And that’s not at all the way that it actually works.”

All the evidence so far says that the current variants can’t make it past the vaccines to the point where we should really worry. We don’t have data on how the New York or Southern California variants respond to the vaccines yet, but scientists should have it “fairly soon,” perhaps in a month or so, says Bryce Chackerian, an immunologist at the University of New Mexico School of Medicine.

Well, since at least one variant does diminish the protection from at least one vaccine somewhat … will we be getting booster shots eventually?

Maybe. “We don’t know,” says Chackerian. “All I can say is that the companies that are making the RNA vaccines”—the new, easily adaptable technology used by Pfizer and Moderna—“are planning for that right now.” Manufacturers are already creating boosters that target either multiple variants or specific variants. An article at PBS explains that it takes about six weeks between getting the genetic sequence of a new variant and having a new mRNA vaccine booster ready to test in humans, plus extra time for clinical trials. In late February, the National Institutes of Health began a phase 1 clinical trial of a Moderna booster targeting the South Africa variant. Johnson & Johnson is also testing giving a second dose of its existing vaccine, and Moderna and Pfizer are testing a third dose. “I think it’s quite possible next fall or winter” we’d get coronavirus boosters along with our annual flu vaccine, Weaver says.

But again, all four experts I checked with said the existing vaccines have proved to be pretty good against the existing variants. The variants “should be motivation to get a vaccine,” says Kennedy. After you do, it’s reasonable to go ahead and take the CDC’s recent advice on socializing for vaccinated people.

But there are an awful lot of people who haven’t gotten the vaccine who are socializing! What do the recent lifts on mask mandates and business restrictions in some states mean for the variants?

Yes, the really concerning thing is that opening up states now, while only about 10 percent of the country has been fully vaccinated, will likely lead to more variants. “The more virus that’s around, the more opportunity there is for new variants,” said Kennedy. Every expert I spoke to agreed that careless reopenings could not just increase cases, but could help the virus mutate in ways that are harder to combat. “I think it’s very risky,” said Weaver. Some of those new variants will inevitably be harmless. But there’s a chance that some will be even more concerning than the ones we are seeing now.

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