Coronavirus strain mutation spreads 10 times faster than original | the Chronicle

Researchers at University of North Carolina (UNC) and University of Wisconsin-Madison in United States they checked that the cepa D614G del SARS-CoV-2 which has mutated in recent months is spreading faster and is more contagious than the original strain that triggered the pandemic in China.

“ The D614G strain outshines and outperforms the previous one by about 10-fold and replicates extremely efficiently in primary epithelial cells, which is an important means of person-to-person transmission. ”Explain Ralph baric, professor of microbiology and immunology at the faculty of medicine at UNC.

The research, published this Thursday in the popular magazine Science, is based on an experiment conducted by virologists from University of Wisconsin-Madison, in which two groups of hamsters were infected with the two strains of the coronavirus and, with them, healthy samples were placed, separated only by a septum.

The result was that both strains of the virus were quickly transmitted to the group of healthy animals. Thus, in the case of the mutant strain, 6 of the 8 hamsters were infected on day 2 and on day 4 all were infected.

For its part, the original strain did not infect any samples in the first two days. However, by day 4, the virus had already been transmitted to all rodents.

In conclusion, the study shows that the mutated virus is not only faster to replicate, but also much more infectious.

On the flip side, this finding hopefully indicates that this strain originated from Europe, which has become the most common mutation of coronavirus, has no more serious implications than the previous one and is even more susceptible to being neutralized by antibodies.

This most vulnerable mutation has spread through the population through the formation of a flap at the tip of the protein peak of the SARS-CoV-2 This causes it to open, which allows the virus to infect more cells, and at the same time, this opening makes it easier for antibodies to infiltrate and inactivate the virus, the researchers explained in their study.

“ The mutation of the virus is transmitted by air better than the original virus, which may explain why this strain has spread so widely among humans ”, stressed the virologist Kawaoka, one of the scientists who participated in the experiment.

Despite the weakness of the virus, scientists insist that “they must continue to trace the consequences of these new changes” for “protect public health as much as possible”.