Several researchers have made conclusions about the ability of the SARS-CoV-2 coronavirus to mutate into more contagious , and perhaps potentially more deadly, strains. This would help to explain (although not completely) the uneven sample of deaths and serious cases in different regions of the world.
In this regard, there are two preliminary studies, that is, they have not yet passed the peer review that is required for a scientific investigation to be sufficiently robust, but which is worth commenting on. These studies conclude that the coronavirus would have mutated into strains, as we said, potentially more contagious. And this entails a much more worrisome result: that the vaccines or experimental treatments that are being developed might not be entirely effective against these mutations , since it would have been taken as a reference to develop it to the initial strain of the virus, that of the Chinese city from Wuhan.
The first one we refer to was published on April 23 on medRxiv, a server for preliminary scientific studies. In it, researchers from the Chinese University of Zhejlang claim to have found new, more virulent versions of the coronavirus, after having managed to isolate up to 11 different strains in Chinese patients, in which they managed to identify 33 different mutations. These mutations would make strain number 11 about 270 times more virulent than the initial strain.
The second study was published on April 30, this time, in bioRxiv. Scientists at Los Alamos National Laboratory in the United States have monitored the mutation in real time in SARS-CoV-2, focusing on protein S, key to infecting human cells. They identified 14 protein S mutations. Since this is the key to entry into human cells, these mutations probably indicate greater contagiousness in the new strains.
But also, as the researchers in the study indicate, it would make people more vulnerable to a second infection, because people who have passed COVID-19 could have developed immunity for the initial strains of the virus, but not for the mutations. .
A more contagious European strain
This latest analysis, which recognizes a probable greater contagiousness of the coronavirus, establishes that the new mutated strain appeared in Europe in February , and later would move to the United States. Specifically, the mutated strain is said to have infected Italians first, and would later spread throughout the rest of Europe. As for America, it appears, according to the study, that the original strain would have reached the United States, but that it would have been replaced by the mutated version by March 15.
It should be clarified that the study does not indicate that the mutated strains of the virus are more lethal, but only more contagious. But it is concluded that infected people would have a higher viral load, and also a greater risk of suffering serious complications.
The point about virus mutations is not that one strain is substituted for another. As explained in the study: “There is evidence of recombination between strains circulating locally, indicating that there are infections by multiple strains.”
The findings presented here have important implications, not only in the study of coronavirus transmission, but also for the development of immunity treatments, such as vaccines; and viral treatments, which should take these mutations into account to be as effective as possible.
Studies that have not undergone peer review should always be interpreted with caution. Peer review is one of the tools available to the scientific community to ensure the success of the scientific method.
