Coronavirus variant B16172: could it block the UK’s path out of lockdown?
A few weeks of relief from isolation, huddling in your big coats outside chatting to a few friends in the evening after work, beginning to feel optimistic about the roadmap out of lockdown, and then another curveball comes in. This time in the form of the coronavirus variant called B1617 – which was first identified in India. Or rather, to be specific, B16172, because B16171 and B16273 have not shown such an alarming increase in cases.
The rapid increase in the proportion of SARS-CoV-2 sequences in England that are B16172 seem to indicate that its transmissibility exceeds even that of the B117 variant (the so-called Kent variant), which kept the UK in lockdown over the winter.
An initial feeling of unease, given the dreadful situation that has unfolded in India, has given way to genuine concern that this could be the problem that blocks the UK’s path out of lockdown. This would, of course, be a tremendous disappointment to a country that has been looking forward to a summer of freedom.
So perhaps us scientists shouldn’t say anything until we are more sure whether it could be a problem. But the consequences of not saying anything if it does turn out to be a valid concern could be catastrophic, and there may not be much time to act.
If it turns out not to be a problem, then holding our hands up to say: “Sorry, I was wrong,” is easy. What we need to know now is whether immunity imparted by the vaccines works against it. There is very little data on this, certainly not for the B16172 variant.
Very early indications are that there is some decrease in immunity for B16171, but perhaps not as much of a decrease as B1351 (the variant first identified in South Africa) has shown. However, data hasn’t always distinguished between the three different B1617 variants, and B16172 has unique mutations that are of concern, so we need more information to be sure. We also need to check whether this variant might be associated with an increase in the severity of disease. Being cautious about our risks in the meantime is sensible.
It’s a spectrum
Escape from immunity is not all or nothing. Our immune system makes a massively diverse repertoire of antibodies and would never make just one antibody against the virus. So, while a mutation in the virus could result in some of our antibodies not binding to it (to block its activity), there would still be others that could bind to it.
Each of us is unique, as are our immune systems, so we all make a slightly different response to the vaccine. If we have a very healthy immune system that makes a lot of different antibodies in the first place, then losing the use of a few would still leave us with protection.
On the other hand, if we were unlucky enough to not have many antibodies of the appropriate type in the first instance, then losing the use of some might have more serious consequences.
On a population level, this means that the proportion of people that are protected by the COVID vaccines might decrease against a new variant. Until we have more data, though, we won’t know how much of a problem this will be. In the meantime, many people are keeping a close eye on the situation. There are also a lot of people working very hard to roll out vaccines. Please take advantage of this and make sure you get both doses.
Deborah Dunn-Walters receives funding from UKRI and is Professor of Immunology at the University of Surrey. She is also a Trustee for the Dunhill Medical Trust and The British Society for Immunology (BSI). She chairs the BSI COVID-19 Immunology Taskforce.