The Brazilian virus variant P.1 has so far been detected in 19 countries – including Germany. And it can be particularly dangerous. This is what British and Brazilian researchers suspect in a study that was published in advance on “Github”, that is, without peer review by other experts. According to them, P.1 appears not only to be significantly more contagious than the wild type of the virus, but also to evade immunity significantly more frequently.
According to the researchers, the new virus variant first broke out in the city of Manaus in the Amazon rainforest. Scientists in the region had previously determined through studies that two thirds of the population had already developed antibodies against the coronavirus. Actually, there should already have been protection through herd immunity. Nevertheless, there was a second wave on site in December, which was significantly more difficult than the first wave in spring 2020.
P.1 replaced all other variants in just seven weeks
Genome and pedigree analyzes by the researchers now show that P.1 is a genetically modified virus and presumably originated from the Brazilian virus strain B.1.1.28, which was first detected in March 2020. They estimate that the variant originated around November 6th. That in turn would mean that P.1. has almost completely displaced all other variants in just seven weeks: in the meantime, almost 90 percent of the cases in Manaus go back to the P.1 line.
However, the researchers could not deduce from further tests whether P.1 infections are associated with an increased viral load or a longer duration of the infection. It is clear, however, that the new variant is responsible for the renewed strong outbreak in Manaus.
In their study, the researchers assume that P.1 is twice as contagious as other previously discovered variants and eludes previous immunity in 25 to 61 percent of all cases. This is the only way to explain the rapid spread in a region where many people have already developed antibodies against the virus.
Mortality is up to 1.8 times higher
Also worrying is that the number of deaths in the region has risen sharply. According to the calculations, the mortality after infection with P.1 is 1.1 to 1.8 times higher than with other pathogens. However, the increased number of deaths is also related to the health system in the region, which has collapsed again.
The mutations found in line P.1 have also been detected in the British virus variant B.1.1.7 and the Brazilian virus variant B.1.1.28. According to the researchers, this would speak against a higher aggressiveness of the line P.1.
The virologists nevertheless warn against underestimating the threat and will continue to closely monitor the spread.