How dangerous is the new coronavirus from Brazil?

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In September the news from Manaus sounded encouraging.

Herd immunity has probably been achieved, it was said at the time from the city of two million in the middle of the Brazilian jungle.

Scientists had determined that 66 percent of the population had been infected with the corona virus at this time.

The horrors of the pandemic and the time of the many deaths seemed to be drawing to a close.

If the common assumptions of science about the coronavirus are correct, it was said at the time, it would soon have to disappear from the former rubber metropolis because enough people have become immune.

But hope was dashed.

At the beginning of this year, epidemiologists were shocked to discover that no herd immunity had been achieved in Manaus.

The number of victims in the clinics and in the cemeteries suddenly rose sharply again.

Imperial College London epidemiologist Nuno Faria now believes he has found an explanation.

And that sounds anything but reassuring.

"We suspect that a new mutant is largely responsible for the renewed increase," he said on Tuesday at a press conference at the British Science Media Center.

P1 is what he and his colleagues call the new variant, which had largely displaced the conventional pathogen in the city after just eight weeks.

The mutant is now found in 87 percent of all samples.

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This observation alone suggests that the new pathogen, which probably first appeared in November, is much more contagious than its older relatives.

According to the estimates of the scientist and his colleagues, the new mutant leaps from one person to another about twice as often.

We don't know exactly yet, the factor seems to be somewhere between 1.4 and 2.2.

However, P1 also had an easy time of it, the scientists admit, because those responsible in the city had loosened the lockdown measures in the meantime.

P1 is not a problem in the Amazon region: this virus variant was also found in infected people in 24 other countries around the world, including Great Britain.

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That alone is hardly surprising, a variant that is more widely spread than the previous ones will find its way around the world.

The mutant P1 worries the experts because it is apparently able to infect former Covid-19 patients.

Although these should have built up a protective immune response after their first infection, P1 was able to infect them.

That, at least in this case, would call the concept of herd immunity into question.

In fact, scientists from the University of São Paulo, among others, have been able to show in laboratory tests that the antibodies of those who are already infected have a significantly worse effect against the mutant.

These are largely responsible for immunity.

61 out of 100 infected people are infected again

According to Nuno Faria, the rate of viruses that can even escape their trained immune system is between 25 and 62 percent.

Applied to the real world, this would mean that out of 100 formerly infected people, up to 61 would become infected a second time with P1.

However, these are only preliminary data that have not yet been published in any scientific journal.

So they have not yet been subjected to their strict control processes.

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However, the experts are certain that the previous value of 70 percent, which was traded as a benchmark for achieving herd immunity, is probably too low.

This applies to all countries in which P1 prevails.

The reinfections from Manaus do not mean that the vaccines against P1 are ineffective.

Neither AstraZeneca's nor Biontech's vaccines have been tested against P1 so far.

But it is already clear that the protective effect of a Covid-19 vaccination is superior to that of a natural infection.

In Brazil, it was mainly the Chinese CoronaVac vaccine that was vaccinated.

However, according to a laboratory study, P1 does not seem to be able to stop.

Source: WORLD infographic

Interestingly, the mutant B.1.1.7, which is currently causing the greatest concern for medical professionals in this country, could protect the world from P1.

At least that's what Sharon Peacock, a microbiologist and public health expert at the University of Cambridge, speculates.

The reason for this is the observation that the Brazilian variant has so far still had difficulties gaining a foothold in the UK.

P1 does not seem to be able to prevail against B.1.1.7.

Peacock's theory: The European virus is possibly even more contagious.

And infects so many people so quickly that too few people are left without immune protection for P1.

This is still nothing more than a guess, stresses Peacock.

But should it be confirmed, the good news would be that no vaccine has had any problems with B.1.1.7.

Can one mutant stop the other?

Something similar can be seen in South Africa right now.

Here variant B.1.351 is now responsible for more than 60 percent of infections, which is very similar to P1 in many ways.

Among other things, the changes in the S protein that characterize both types of pathogen are almost identical.

This is used by the pathogen to dock onto the body cells.

The higher infection rates of the mutants are therefore attributed to these changes.

Also against B.1.351 P1 has apparently not yet achieved anything.

Science is now looking with excitement to São Paolo, where both virus variants are currently meeting.

If B.1.1.7 prevails, P1 will probably not be able to spread particularly well in the rest of the world.

The vaccine manufacturers have already started to optimize their vaccines for the different variants.

According to Sharon Peacock, the first adapted vaccines are already being tested in studies.

Biontech is also checking whether a third dose also offers better protection.

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It is possible, speculates Sharon Peacock, that the new variants of the pathogen are already so good that they cannot spread any faster.

If this stage of optimal fitness, as experts call it, already existed in the current mutants, this would mean: In the future, every new variant that forms will disappear by itself: For molecular biological reasons, it could not become more infectious than B. 1.351, B 1.1.7 or P1.

The new variants would not be competitive.

It is clear, however, that further mutations will form.

Because the more infected there are, the more genetic changes can occur.

100 million people around the world are currently infected.

"I am convinced that if we started looking all over the world, we would find a lot more mutations now," says Nuno Faria.