Shafaq news/ global study has found strong evidence that a new form of coronavirus has spread from Europe to the US, The new mutation makes the virus more likely to infect people but does not seem to make them any sicker than before, an international team of researchers reported Thursday.

"It is now the dominant form infecting people," Erica Ollmann Saphire of the La Jolla Institute for Immunology and the Coronavirus Immunotherapy Consortium, who worked on the study, told CNN.

The study, published in the journal Cell, builds on some earlier work the team did that was released on a preprint server earlier in the year. Shared information on genetic sequences had indicated that a certain mutant version of the virus was taking over.

Now the team has not only checked more genetic sequences, but they have also run experiments involving people, animals and cells in lab dishes that show the mutated version is more common and that it's more infectious than other versions.

"We do know that the new virus is fitter. It doesn't look at first glance as if it is worse," Saphire said.

The study, published in the journal Cell, confirms earlier work suggesting the mutation had made the new variant of virus more common. The researchers call the new mutation G614, and they show that it has almost completely replaced the first version to spread in Europe and the US, one called D614.

The new version seems to multiply faster in the upper respiratory tract -- the nose, sinuses and throat -- which would explain why it passes around more easily, the researchers said.

But tests on 1,000 hospitalized coronavirus patients in Britain showed those infected with the new version did not fare any worse than those who caught the original strain.