(Bloomberg) -- A Minnesota resident who was recently in New York City has tested positive for the omicron variant of Covid-19, according to New York and Minnesota officials.

The adult, a vaccinated man, developed mild symptoms on Nov. 22 and sought testing on Nov. 24. His symptoms have resolved. The person reported attending the Anime NYC 2021 convention at the Javits Center from Nov. 19 to Nov. 21. About 50,000 attended the event on Manhattan’s West Side.

The case is the first confirmed for Minnesota, and the second in the U.S.

“This news is concerning, but it is not a surprise,” Minnesota Governor Tim Walz said Thursday in a statement.

Health officials around the world are racing to understand the severity of omicron, which was first identified in South Africa. Cases have been reported across Europe and in Australia and Canada. 

The first U.S. case was reported Wednesday in California, a San Francisco resident who had traveled to South Africa.

The new variant was identified just as New York and others parts of the U.S. begin to see the effects of a winter surge and holiday gatherings.

New York, the early center of the pandemic, has more than 3,000 people hospitalized for Covid-19. A month ago, it had fewer than 2,000. The Finger Lakes and Western New York regions are faring the worst, with positive-test rates of more than 10%. New York City is around 2%.

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