Closing the barn door after the virus has escaped

When will we learn? For the past two or three weeks, the world has been fretting over a new Covid-19 virus variant, one that UK Prime Minister Boris Johnson announced was significantly more transmissible than other variants.

Johnson’s announcement has led multiple other countries, including the U.S. and France, to temporarily ban travel from the UK. As scientists began testing for the new variant, at least 3 states in the US–California, Colorado, and Florida–have already reported that they are detecting the new variant too. Expect many more states (and other countries) to report finding the variant in the coming days.

In the UK, the new variant was first detected in September, and by November one-fourth of the cases in London were caused by this variant. That does seem worrisome.

My first reaction upon hearing of this new variant was to ask whether it really is more transmissible or not. The evidence is very preliminary, and it’s still not peer-reviewed, but a very new study from a week ago says that yes, the new variant is 56% more transmissible.

Okay then, that’s not great. But there’s no evidence that the new variant (known variously as B117 or VOC 202012/01) is more deadly, or that the vaccine won’t work against it. It just spreads faster.

My second reaction was about these new travel bans. Why would anyone think that the variant was only in the UK, merely because the UK was open about reporting it? Unless we really know that to be a fact, travel bans are a classic case, as the adage goes, of closing the barn door after the horse (the virus) has escaped.

So has the B117 virus has already spread well beyond the UK? Yes, it appears so.

In a new study released just two days ago on medRxiv, scientists at Helix, a company that has tested millions of samples for the presence of the SARS-CoV-2 virus, looked back at their testing data over the past several months. They found that evidence of the B117 virus in the US extends back at least to October. They also found that the variant is now spreading in the eastern US, in Massachusetts, Ohio, and Florida.

An important caveat is that Helix’s tests weren’t specifically looking for the B117 strain. They instead looked at two key deletions in the spike protein (which I’ve discussed before) that the B117 strain contains, and that their tests can also detect. It might be that they found slightly different strains that shared these deletions, but even if the strains they detected weren’t identical to B117, it’s possible they were equally infectious.

So yes, the new strain seems to be in the US already, and it seems that it’s been here since October. And if it’s been in the UK since September, and the US since October, well then it’s a darned good bet that it’s pretty much everywhere. Banning travel from the UK not only punishes the UK for openly sharing its findings, but it also may prevent other countries from sharing information about newer strains of the virus, should those emerge.

What should we do in response to the new strain? The most effective action will be to roll out vaccines even faster, something that public health authorities across the US are trying to do. So far it is not going well, in part because we have no consistent national strategy. It’s not too late to fix that.

But let’s not pretend that travel restrictions now will do anything to keep this new strain locked up. They’re just closing the barn door after the horse has escaped. Or “Vijgen na pasen” as they say in Flemish, or “arriver apr├Ęs la bataille” in French. There’s an idiom for this behavior in every language, it seems.

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