Every time a virus duplicates, there’s a chance of a mutation. With millions of people infected by SARS-CoV-2 and trillions of viruses circulating, the number of variations that develop is daunting. However, only a relatively tiny number of changes have turned out to offer the virus an advantage in terms of spreading to additional hosts. Right now, it appears that existing vaccines will provide an adequate response to the variants we know about, but new variants could build on those changes, and the next round of variants could build on those changes, until eventually versions of the virus appear that aren’t adequately addressed by current vaccines. Already the Brazil P.1 variant carries over a dozen changes, making it a serious concern.
So it’s a good thing that vaccine manufacturers are already working to include the newest variants into updated vaccines. Getting these vaccines to patients before that near-inevitable change occurs is going to be a race, and both the virus and the vaccine manufacturers are already running.
Meanwhile, President Joe Biden is planning to increase the rate of vaccination. Which is good. Not just because it means getting life back to something like normal more quickly, but because that’s a key part of the race against variants that may be more contagious, more evasive, and even more deadly.
Before taking office, Biden set a goal of 100 million doses of vaccine in 100 days. That’s a higher sustained rate than anything seen so far in the U.S., and it’s an impressive-sounding goal. It’s also not enough. Even including the 25 million Americans who have tested positive for COVID-19, reaching the 75% or greater levels required for herd immunity by summer would take a rate of over two million Americans being injected each day. On top of that, some officials have stated that the “100 million doses” claim really only represents 50 million Americans since the two vaccines available in the U.S. at this point both require two doses. If that’s the case, we’d need to more double that rate to reach herd immunity by the end of the year.
That sounds like a tough challenge. Because it is. However, there are some good reasons to think it’s a challenge that can be met. For one thing, there are now people in charge who are focused on getting vaccine not just shipped, but into the arms of Americans. As The Washington Post reports, Biden has upped his target for the number of injections to 1.5 million a day, though he didn’t give a date for when that goal might be reached. The 1 million injections rate was reached in four of the last eight days, so clearly that can be met. It’s keeping that rate sustained—and increasing it—that could be a challenge.
However, a big boost to that effort might be coming soon in the form of a vaccine that requires just one dose and doesn’t require extreme cold temperatures for storage. The Johnson & Johnson vaccine entered phase 3 over a month ago and is expected to provide interim data within the next week. Based on the timelines of Pfizer and Moderna, that could see Johnson & Johnson wrapping up their trial by mid-February and obtaining an emergency use authorization from the FDA by the end of the month. Johnson & Johnson alone has promised 100 million doses for the U.S. this year. And since it’s one dose, one person, that’s about a third of the population. So—assuming that Johnson & Johnson’s phase 3 results are even close to as good as those from Pfizer and Moderna—a big boost in vaccine availability could be on the way. (Note that there are reasons why Johnson & Johnson’s more traditional adenovirus-based vaccine could be less effective than the new mRNA vaccines from Pfizer and Moderna. That was already seen in the results from AstraZeneca. So those interim numbers are going to be very interesting.)
In any case, the biggest reason to get vaccines administered as widely and as rapidly as possible isn’t so that businesses can reopen or schools can go back to in-person classes. It’s so that we stand a chance in that variant race. The more active cases of COVID-19 there are out there in the world, the more chance there are of variants arising that are more contagious. And as far as evolution is concerned, more contagious is about the only thing that counts.
There are diseases where evolutionary pressure has, over time, pushed toward less virulent forms that generate milder disease. But those pressures are all but absent with SARS-CoV-2. That’s because this virus does almost all of its spreading in the days shortly after infection, often before symptoms even set in. 100% of those catching the virus could burst into flames on Day 30, and it would have almost no impact on the rate of spread—except that such an outcome might make governments and individuals take the disease more seriously.
As the vaccine goes out, the relative selective pressure on the virus changes. A version that can get around the vaccine protection doesn’t become more likely—the variations that appear are still more or less random—but eventually a point comes when those variants that can best avoid immune response from vaccines and previous infections are the only versions that can spread widely. Those versions then get a tremendous advantage over other variants even if they are not any more contagious in a population where the virus (and vaccine) were unknown.
Which is why it’s startling to hear that several new variants, including Brazil P.1, that carry one specific change to the spike protein are about one-sixth as sensitive to the antibodies generated by vaccine or previous infection than virus that doesn’t carry this change. That may sound like the peal of doom. However, the truth is that both the Pfizer and Moderna vaccines produce a large enough antibody response in people that they should still overwhelm these new variants. Most people who had even a moderate case of COVID-19 should also retain good protection against the new variants. However, those who didn’t develop a strong immune response, either from the vaccine or the virus itself, are certainly more open to infection. If the Moderna and Pfizer vaccines were to rerun their phase 3 trials in a pool of patients carrying these new variants, it should be expected that both would lose something from the 94% and 95% efficacy they respectively showed just a couple of months ago.
Our edge over the virus is eroding. Both Moderna and Pfizer are at work updating their vaccines. Moderna in particular has suggested that it might develop a booster shot—essentially a third dose of their vaccine—that is targeted at these new variants. Going forward, it can be expected that all vaccine manufacturers might rework the variations on the spike protein into their vaccine formula. However, it’s unlikely that any vaccine carrying the changes would arrive before next winter.
There’s no reason to think that the SARS-CoV-2 virus is going to be with us forever; that we’re going to have to line up for our annual COVID-XX shot along with our flu shot. Indications now are that immunity to this virus is long-lasting. The worst fears—that immunity might soon fade, that vaccines might be effective for only a period of weeks—have all turned out to be not true. Also, while the news may make it seem as if SARS-CoV-2 is ever-shifting (and it is), the truth is that this virus lacks the handy-dandy set of interchangeable proteins that make the flu such an eternal bastard.
This thing can be beaten and stay beaten. But to get there, we can’t squeeze it in a vise of slowly administered vaccines. We have to hit it with a hammer. The rate of vaccine administration needs to increase. It needs to increase rapidly. It needs to increase significantly. It’s a race. And the virus never stops running.