Corona: How escape mutants can destroy vaccination progress

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For the first time in over a year, people are hoping that the pandemic may finally change for the better. Almost a third of Americans are fully vaccinated. Europe is well on the way to being fully vaccinated by the end of summer. According to the RKI, more than 23 million people in Germany received their first dose.

In fact, we are in one of the most precarious moments of the pandemic – a critical race between vaccines and mutations in the virus. Despite all the progress that we have made in recent months, the outcome is anything but certain. Less than one in ten people in the world has received a single dose of a Covid-19 vaccine while new mutants of the virus are spreading.

The situation is very worrying. “It doesn’t look good, to be completely honest,” said virologist James Hildreth from the Advisory Committee of the US Food and Drug Administration (FDA). Hildreth is responsible for the approval of the Covid-19 vaccines. “It almost seems like the availability of vaccines has caused some people to give up their vigilance a little too soon.”

Scientists have observed the virus as new and sometimes more contagious mutations gained the upper hand. “By November, most people ignored the mutations,” says epidemiologist Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “They were more of a curiosity.”

The big question now is whether everything is already known about the previously known mutations – or whether there is more to come. Scientists don’t seem sure yet.

There are three ways the variants could win

The bad news is that the limited vaccination rate means that the virus has many opportunities around the world to look for gaps in our immune system. Since the coronavirus is constantly evolving and adapting to its habitat – that is, to us – it tries to survive by generating the “most suitable” version of itself. The current vaccines, however, were developed against the original variant, which was discovered in China almost a year and a half ago.

This version of the virus barely exists because it has been supplanted by newer variants – including those that have been shown to be more easily transmitted or that are more resistant to some vaccines. B.1.1.7, the variant first identified in Great Britain, now dominates the infection process in Germany.

The good news is that the vaccines are so strong that they have withstood the mutations well. In addition, almost all of the major pharmaceutical companies are making efforts to develop new vaccines and booster vaccines – in the hope that they will be one step ahead of the variants.

However, there are three ways the virus could outsmart our vaccines. First – and this is crucial – all of the vaccines we have target the coronavirus spike proteins. These are the sharp, crown-like bumps on the surface of the virus that help it enter our cells. If several strong mutations occur in these proteins, this could make our current vaccines unusable: the induced antibodies would not be able to fight back the new variant. The P.1 variant, for example, which was first identified in Brazil, has three mutations on the spike protein and re-infects people who have already contracted Covid-19.

A second possibility would be so-called “escape mutants” or “escape mutants”. These are variants of the virus that our immune system does not recognize immediately and therefore have a better chance of multiplying and infecting the population. “We’re not too far off,” says Ravindra Gupta, a professor of microbiology at the University of Cambridge. He studied the E484K escape mutation, which is already present in almost all mutations.

Third, no one knows how long our current vaccines will provide full protection against the virus. What the scientists know, however, is that the vaccine protection will not last forever. That could mean that people who have been vaccinated become vulnerable to the virus again in the years to come. “We have to start planning for the next generation of vaccines this summer by fall,” said Ashish Jha, the dean of Brown University School of Public Health.

The greatest hope

Even if we vaccinated a large percentage of the population, people who are immunocompromised will remain susceptible to Covid-19. If we don’t get the pandemic under control quickly enough, unvaccinated people could become the perfect breeding ground for new mutations. It is therefore wrong to say that young people do not need to be vaccinated: protection that only covers half the population is not enough.

Even if flight mutants don’t ruin our progress, the global outlook for the next few years may not be so rosy. While the US, Europe, Israel, and perhaps a few other nations are getting vaccinations high enough to contain the virus for occasional outbreaks, the rest of the world will continue to face a full-blown pandemic.

According to the scientists, however, there is also reason for hope. Because the advantage of mRNA vaccine technology is that it trains the body to fight the virus itself. In addition, mRNA vaccines can be adapted to new variants within a few weeks. Since only a few mutants of the corona virus appear to be responsible for the majority of the current cases, it may well be that these can be contained with a second generation of vaccines. Biontech / Pfizer and Moderna are already working on their booster vaccinations.

The scientists also hope that, given all the knowledge about the new variants, one day they could develop a single multicoronavirus cocktail that could stand up to all threats.

The greatest threat

So the biggest threat is our own complacency. From a global perspective – and this is the only one that counts in an epidemiological catastrophe of this magnitude – the situation is turning more negative than positive. In the past two weeks, more cases of Covid-19 have been reported worldwide than in the first six months of the pandemic – more than half of them in Brazil and India. Experts fear that it is precisely there that escape mutants could emerge that are able to bypass our immune system.

After a pandemic for over a year, people often see the vaccinations as a kind of free pass. In India, tens of millions of people recently flocked to the Kumbh Mela, one of the largest festivals in the world, and many of them fell ill afterwards. Japan is still pushing to host the Summer Olympics this year, even though it has only had the majority of its Covid-19 deaths in the past few months.

At the moment we’re like a cocky boxer dropping cover on the final lap. Although the virus is on the ropes, we’re just giving it the chance to land a knockout blow. With vaccination rates still low around the world, the urge for freedom could allow the development and spread of more mutants. Until we are able to achieve near herd immunity, say the scientists, vaccinations alone are not enough. So basic preventive measures like masks and clearance are still essential to stop the virus from spreading.

This article was translated from English by Steffen Bosse. You can find the original here.


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