By Deena Beasley

(Reuters) – 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 on Wednesday.

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% of cases, researchers at Columbia University Vagelos College of Physicians and Surgeons, said on Wednesday.

The variant was also described in research originally published online February 15 by California Institute of Technology scientists. Neither study has been reviewed by outside experts.

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.

“Instead we found high numbers of this home-grown lineage,” Dr. Anne-Catrin Uhlemann, assistant professor in the division of infectious diseases at Columbia University’s College of Physicians and Surgeons, said in a statement.

The Columbia study was designed to search genomes from patient samples for mutations associated with worrisome British, South African and Brazilian virus variants. One mutation, E484K, in a genome region encoding the virus receptor binding domain, has been shown to be an escape mutation that greatly reduces the effectiveness of monoclonal and vaccine-induced antibodies.

Of the 65 virus samples containing the E484K mutation Ho’s team identified, a handful represented cases involving the known concerning variants, but 49 of the 65 belonged to the new New York B.1.526 lineage.

Studies have shown that recently launched coronavirus vaccines are still likely to neutralize the virus and protect against severe illness, even for infections with new variants. Vaccine makers are also working to develop booster shots to combat mutated versions of the virus.