Finnish specialists say they are "worried" about the emergence of a new coronavirus variant with an unusually high number of mutations first detected in southern Africa.

The variant is currently called B.1.1.529 but is likely to be given a Greek code-name by the World Health Organisation on Friday.

Tuomas Aivelo, a postdoctoral researcher in viral ecology at the University of Helsinki, told Yle's breakfast show Yle Aamu on Friday morning that this latest variant is the most concerning development since the outbreak of the Delta variant.

"There are a huge number of mutations in this variant than have been seen in previous variants, but now there are many within the same variant. Now these mutations appear to increase infectivity, making it more likely they will evade immune protection," Aivelo said.

This means that the Covid vaccines currently in use may not be as effective in protecting people against the variant.

"That is the million-dollar question," Aivelo said.

The BBC wrote that one scientist described the long list of mutations linked to the new variant as "horrific", further reporting that mutations have been detected in Botswana and Hong Kong as well as in South Africa.

On Friday Israel confirmed a case of the new variant in a traveller who returned from Malawi, along with two other suspected cases, all in people who had been vaccinated.

"This variant did surprise us, it has a big jump on evolution [and] many more mutations that we expected," Professor Tulio de Oliveira, the director of the Centre for Epidemic Response and Innovation in South Africa, told the BBC.

However, a multitude of mutations does not necessarily mean that they are all highly contagious, and researchers are currently working to find out how these mutations behave.