The new variant, called XEC, was spotted in Germany in June and has since appeared in the UK, US, Denmark and several other countries.
XEC was found to have several new mutations that could help spread the strain this fall, although experts believe the vaccine should help prevent more severe cases.
Professor Francois Balouk, director of the Institute of Genetics at University College London, said that XEC could become the dominant subvariant during the winter, "BBC" writes.
The four most common symptoms
The symptoms experienced by patients with the XEC variant are similar to cold and flu symptoms, as before, and the four most common are: high fever, aches, fatigue, cough or sore throat.
Most patients feel better a few weeks after infection, but recovery may take longer.
Mike Haney, an analyst who analyzes data on Covid, points out that there has been a strong increase in the number of patients with the XEC variant in Denmark and Germany.
At the same time, fewer routine tests are performed than before, so it is more difficult to detect how much of this virus is actually present.
The UK Health Safety Agency (UKHSA) says it is normal for viruses to mutate and change.