How worried should we be about Covid-19 variants?

“We must be humble in the face of nature,” said Boris Johnson in his “road to freedom” speech last week. While insisting we’re on a one-way route out of lockdown, and that vaccination has dramatically changed the odds in our favour, he also acknowledged that we’re dealing with an unpredictable force. It “may seem arrogant to impose any kind of plan on a virus,” the PM said.

In many ways, the humbler, less combative tone reflects a wider shift in people’s perception of the pandemic – and it’s one largely driven by fears surrounding mutations.

The emergence of new variants has left us on edge. While encouraging vaccine news keeps pouring in (last week, one dose of the Pfizer and AZ vaccine was found to cut hospitalisations by 85 per cent and 94 per cent respectively), there is an underlying sense of fear: with the coronavirus constantly evolving, no-one can be sure how much longer our current vaccines will continue to shield us.

For some, the mutating virus has come to represent a hydra-like monster, that could sprout another ugly, vaccine-dodging head just when we thought this nightmare was coming to an end.

But how worried should we really be about vaccine-resistant mutations undermining all of our efforts?

New variants undeniably raise concerns. Monitoring the evolution of the virus is a vital task and attempting to slow down the rate at which the virus mutates is a key rationale for the cautious lifting of lockdown.

Yet we shouldn’t let fears about mutations overwhelm us. Aiming to “beat” or “eradicate” the virus is probably not the right approach. But there is plenty of reason for optimism. New variants are very unlikely to trap us in a perpetual cycle of lockdowns for years to come. Rather, vaccines will continue to provide us with high levels of protection, until a point, perhaps not too far away, where we may not even need them at all.

Before going any further, it’s important to establish what exactly mutations are. Mutations emerge and disappear continuously. There will have been thousands of slightly different versions of the virus since the pandemic began, and most have no effect on how it functions. There will always be different strains of the virus circulating, but currently the key variants of concern are the South African variant, the Brazilian variant and the home-grown Kent variant. These variants contain a different collection of mutations, but some common changes have emerged in all three. The N501Y mutation, which made the Kent strain more contagious, has been acquired by all of them. And both the South Africa and Brazil strains contain the primary mutation of concern – E484K – which has been shown to pose some resistance to the vaccine. More recently, this troublesome mutation has also emerged in the Kent strain, but only in a small number of cases.

Results from a Novavax trial, recently conducted in South Africa, paints a picture of how variants are impacting the vaccine: two shots of the jab were found to be 95.6 per cent effective against the “original” coronavirus, 85.6 per cent against the Kent variant and 60 per cent against the South African variant.

While nobody can stop a virus from mutating, keeping cases low is the best way to slow it down: “The more the virus is allowed to spread, the more chance it has to evolve and form new variants,” says Professor Lawrence Young, a virologist at Warwick Medical School.

While our vaccination efforts are impressive, they don’t necessarily detract from the importance of keeping cases down. When it comes to slowing down the rate at which the virus mutates, vaccination itself is a double-edged sword. On the one hand, it reduces the amount of virus circulating, on the other, vaccination increases the selection pressure on the virus, encouraging vaccine-resistant mutations to evolve. Mutations that are able to dodge the immune response generated by the vaccine are in a stronger position to spread.

As some scientists have pointed out, vaccines are normally given ahead of exposure. Vaccinating at a time when there are high levels of infection is quite an unusual situation, and one which will encourage mutations even more than normal.

This may paint a gloomy picture, but in fact there is every reason not to lose faith in the vaccination programme as our way out of this mess.

When we hear about new strains compromising vaccine efficacy, the first thing we should be asking, according to Dr David Matthews, a virologist from Bristol University, is: “Efficacy against what?” Infection or serious illness? There’s a big difference between a new variant that manages to still infect a vaccinated individual and one that causes them to get seriously ill. “Really, the vaccine is to stop hospitalisations and death,” says Dr Matthews. “When we have a variant that evades the vaccine to the point that it’s putting people in hospital, that’s when it’s time to get worried. I’m not convinced that any of the variants around so far are grounds for changing the vaccine.”

When we do reach that point, the good news is that vaccines can be tweaked with relative ease. Pfizer-BioNTech, Moderna and Astra Zeneca are already working on modifications to target the South African strain. Last month, the UK formed a partnership with German biopharma company CureVac to develop vaccines against new Covid-19 variants.

The UK’s Vaccine Deployment Minister, Nadhim Zahawi, is confident that we can have an updated vaccine ready by autumn, if necessary.

The cutting-edge mRNA technology, used in the Pfizer-BioNTech and Moderna vaccines, is especially adaptable. Ugur Sahin, CEO of BioNTech, has confirmed: “we can change the sequence of the vaccine within a few days, and we could deliver a new vaccine within six weeks in principle.”

When it comes to monitoring new strains in order to make appropriate tweaks, “surveillance using genomics is so important,” says Prof Young. “And we happen to be quite good at it in the UK.” It’s safe to say this is an understatement; the UK has carried out over half of all Covid genome sequencing worldwide.

Of course, another fear is that just as we’ve rolled out a tweaked vaccine, a new variant emerges. But one reassuring trend, according to Prof Young, is that, in different parts of the world, we’re seeing common changes occurring. “Even though these are independent lineages of the virus, they are going down the same route.” In fact, this isn’t surprising. Since the virus is experiencing similar evolutionary pressures, it makes sense that similar mutations would crop up.

Now that we’ve observed the popular routes the virus is taking to dodge the body’s immune system, “it should be possible to design a vaccine that will hit the common changes and cover a range of different variants, perhaps ones we haven’t even seen yet.”

At some point, we may not even need a vaccine to tackle virus variants at all.

“Eventually this virus will establish itself as just another common cold virus,” says Dr Matthews. It will become “like one of its cousin coronaviruses”- which generally cause sniffles rather than death.

Covid-19 is very unlikely to be eradicated but, according to Dr Matthews, humans and the virus will find a way to “co-exist”.

A failure to eradicate the virus does not mean we’ll live in constant fear of new mutations popping up. History shows us that we don’t so much beat pandemics as learn to live with them. Once diseases emerge, they rarely leave. In fact, smallpox is the only human disease to have been eradicated through vaccination. But, much like the Spanish Flu, as immunity from the coronavirus builds, its power will gradually fade.

There will not be a definitive moment where humanity triumphs over the virus and Covid-19 raises its white flag, which is why the war metaphors that have crept into the narrative surrounding the coronavirus are misguided.

Exactly how long it will take for the virus to loosen its grip on us – and how many more deaths we will have to endure first – is, of a course, the burning question. And it’s one to which nobody can provide a definitive answer.

But Dr Matthews is optimistic: “Looking at all the recent data, it’s possible that we’ll see this virus as a public health concern fade away over the next year or so.” He suspects that the virus could, in a relatively short space of time, become less deadly than seasonal flu. A big clue is that the coronavirus, unlike the flu, isn’t seriously affecting babies and young children. “This may well mean that it’s less efficient than the flu at slowing down the immune system and that once people have been vaccinated or had their first exposure, we’ll be OK.”

Prof Young is similarly hopeful that “we are heading into the final furlong.” While we’ll still have to control local outbreaks with an effective test and trace system, he believes another national lockdown is unlikely. For him, “the biggest concern is not variants, but low vaccine uptake.” The other pressing issue, he says, is ensuring global access to the vaccine. “There will be large swathes of the world that will be unvaccinated for a long, long time and that’s where we have an additional responsibility.” Indeed, half of the world’s vaccine supply so far has been reserved for just 15 per cent of the population.

Even with the threat of new variants looming, there’s reason to feel hopeful that Boris’s promise of an “irreversible” unlocking will bear fruit. Vaccines are likely to shield us from illness for quite some time and when tweaks are necessary, they should be fairly easy to execute. Soon enough, the virus may have faded to a point where a vaccine isn’t even necessary at all.

But in the meantime, we shouldn’t be driven into a pit of despair by the virus’s inevitable mutations. We’d be wiser to focus our energy on factors over which we have more control, namely, ensuring as many people as possible can benefit from the high level of protection the vaccine provides.