A new coronavirus variant that shares some similarities with a more transmissible and intractable variant discovered in South Africa is on the rise in New York City, researchers said.

The new variant, known as B.1.526, was first identified in samples collected in New York in November, and by mid-February represented about 12 per cent of cases, researchers at Columbia University Vagelos College of Physicians and Surgeons, said.

The variant was also described in research published online this week by the California Institute of Technology. Neither study has been reviewed by outside experts, Reuters reported.

The Columbia researchers said an analysis of publicly available databases did not show a high prevalence of coronavirus variants recently identified in South Africa and Brazil in case samples from New York City and surrounding areas.