Results will still take at least two weeks, Tulio de Oliveira, a bio-informatics professor who runs gene-sequencing institutions and advises the government on the pandemic, said by phone on Friday. Institutions are breeding the virus and then experimenting on it, he said, not just in South Africa but around the world.

“I am very, very worried,” he said of the virus variant, which has more mutations than earlier incarnations and has already been detected in Botswana and Hong Kong.