The Centers for Disease Control and Prevention’s airport screening program has detected multiple cases of the new COVID-19 variant NB.1.8.1, which has been linked to a large surge of the virus in China.

Cases linked to the NB.1.8.1 variant have been reported in arriving international travelers at airports in California, Washington state, Virginia and the New York City area, according to records uploaded by the CDC’s airport testing partner Ginkgo Bioworks.

Details about the sequencing results, which were published in recent weeks on the GISAID, or Global Initiative on Sharing All Influenza Data, virus database, show the cases stem from travelers from a number of countries, including Japan, South Korea, France, Thailand, the Netherlands, Spain, Vietnam, China and Taiwan. The travelers were tested from April 22 through May 12, the records show.