Health Minister Joe Phaahla on Thursday said that a new coronavirus variant has been found in South Africa.

The newly-detected one causes concern among scientists as it posts high numbers of mutations and fast spread among the young population of Gauteng, a province that houses the majority of the population, AP News reported.

Several new variants, even those with disturbing mutations, often die as the coronavirus evolves and spreads. Scientists are on the lookout for probable changes that could be more infectious or fatal. They, however, single out whether new variants can affect public health.

In an online press conference, Phaahla said that the country has seen a significant increase in new cases.

“Over the last four or five days, there has been more of an exponential rise,” he said, noting that the increase in cases could have been caused by the new variant.

It has been ongoing work for scientists in the country to determine how much the new variant drives the new infections.

He said that the new variant, identified as B.1.1.529, has also been detected in South African travelers in Hong Kong and Botswana.

A meeting was set on Friday by the World Health Organization’s technical working group for an assessment on the new variant.

In the same meeting, they might also come up with a decision on the naming of the new variant.

With the new concern, a flight ban from South Africa and five other southern African countries was announced by the British government. The country said anyone who landed from the identified countries are requested to undergo coronavirus testing.

According to the U.K. Health Secretary Sajid Javid, there were worries that the new variant “may be more transmissible” as compared with the delta strain and “the vaccines that we currently have may be less effective” against it.