Even if new variant of COVID-19 isn't in North America, we might have made our own: expert
'It would be astounding if we didn't have similar variants here,' says former Harvard Medical School prof
While we don't know if a new variant of COVID-19 has spread from the U.K. to North America, it's "very likely" that other mutations of the virus have already happened here, says a former Harvard Medical School professor.
"It would be extraordinarily unlikely that as many as 300,000 visitors from the U.K. per month, over the last four months, have not brought some of that here," William Haseltine, a ground-breaking researcher who is now president of the global health think tank Access Health International.
"But even if none of them brought it here, it's very likely that we have created our own home-grown variants," he told The Current's guest host Laura Lynch.
"[In the U.S.] we have the world's largest population of infected people. We have many people under various kinds of treatments. It would be astounding if we didn't have similar variants here. We just haven't looked."
U.K. Prime Minister Boris Johnson announced the new strain of the virus Saturday, along with tough new restrictions that prohibit many Christmas celebrations. The announcement prompted many countries to restrict flights from the U.K.
The variant is not the first new mutation of the pandemic virus to emerge, but is said to be up to 70 per cent more transmissible than the previously dominant strain in the United Kingdom. South Africa has also announced a variant of the virus, separate from the one seen in Britain.
Haseltine spoke to Lynch about how variants of viruses arise, and what can be done to curb them. Here is part of their conversation.
I'm wondering what your reaction is to what we've been hearing about this new variant of COVID-19 in the United Kingdom.
Well, there are new variants popping up in parts of the world, certainly this variant in [the] U.K. is concerning for some of the reasons you just heard. There's a similar variant, but [an] independent variant, in South Africa with many of the same characteristics. And what it's taught us is that this virus is far more capable of change than we had anticipated and that some of those changes are quite concerning from a public health point of view. It may be more transmissible. It appears to affect children more seriously, and it has some capabilities to evade at least some of our immune defences. Those are all very concerning. And it would be very surprising if many more of these variants aren't already present, particularly in the United States, which is so heavily infested.
Yeah, I want to talk to you about that more in a second, but I just wonder if you could tell us about … what's known about how this mutation came to be?
Well, when you have a large number of people infected with viruses, the viruses try to adapt to that situation. And the way they do that is they create random changes. Each person may have several hundred trillions of viruses in their body during an infection, and each one of those viruses is slightly different from the other…. It's what we call machine intelligence, throwing a lot of random combinations to try to solve a problem. The problem this virus is trying to solve is how to get around in the human population. And it seems to be doing it very successfully.
Now, in particular, when you have some patients, for example, who are immunosuppressed, and you give them convalescent antiserum, that is serum from people who have recovered. You are creating a condition almost ideal for viruses to become resistant to those antibodies because it turns out the convalescent antiserum doesn't completely play with the infection, it comes back more resistant. You can give more convalescent antiserum from a different patient and you're actually teaching the virus how to evade our natural immune responses.
Is that why this new mutation seems to be spreading so fast, because it's learned how to get around the defences so well?
It's learned to do two things. It's learned how to survive in an environment where the body is trying to suppress it. One way it can do better is to attach to cell surfaces more tightly. That has both the effect of allowing the virus to get around in the body that's trying to stop it, and get from one person to another more quickly and incidentally, into children who have less of a receptor. If it can combine more tightly to receptors, you don't need as much virus, you don't need as much receptors, and children have fewer receptors. And I think that is a consistent hypothesis of what this virus is doing, in addition to creating mutations that avoid the most prevalent antibodies that we make to protect ourselves.
We're anticipating some relief as the vaccines are rolling out. Will they work on this new variant of COVID?
You know, they will probably work partially, but we don't know that yet. They may work fully. They may work partially or in some cases for some variant. They may not work. You know, we're used to this kind of situation with the flu. We know that two things happen with flu vaccines. One, the virus can adapt and get around them, and two, that immunity to the flu vaccine doesn't last very long anyway because the antibodies fade.
And will that mean that we will need new vaccines?
It'll mean we need variants of vaccines…. A good thing is some of the types of vaccines — the messenger RNA vaccines — are ideally suited to be tailored to the current strains of virus. The next batch of such vaccines that are made can be specifically tailored to what's being found.
I just want to ask you why you are so certain that this mutation has arrived in the United States and presumably Canada as well?
You can't be certain until you find it. It would be extraordinarily unlikely that as many as three hundred thousand visitors from the U.K. per month over the last four months have not brought some of that here. But even if none of them brought it here, it's very likely that we have created our own home-grown variants, as they have done in South Africa … We have many people under various kinds of treatments. It would be astounding if we didn't have similar variants here. We just haven't looked. That's something else we have to do. We have to ramp up our sequencing to see what's there. We're blind to what's happening in our own country.
Written by Padraig Moran and Lito Howse. Produced by Lindsay Rempel, Cameron Perrier and Joana Draghici. Q&A has been edited for length and clarity.