The new, highly mutated Covid omicron variant is expected to hit New York state in the “coming days,” the state’s health commissioner said Thursday.

“We now have an exposure. We fully expect that it will be detected in the coming days.” said Dr. Mary Bassett, who stepped in as state health commissioner on Wednesday. Bassett was speaking at a news conference alongside New York Gov. Kathy Hochul after Minnesota officials confirmed a second U.S. omicron case in a local man who had just returned from a convention in New York City.

“There’s no question that it will be detected in New York state and in New York City, but it has not yet been detected,” Bassett said.

The Minnesota man, who was fully vaccinated and has since recovered, developed symptoms and was tested shortly after returning from the city to attend the Anime NYC 2021 convention at the Javits Center from Nov. 19 to 21, the department said Thursday.

Anime NYC did not immediately respond to CNBC’s request for comment.

Hochul noted that all convention attendees were required to get vaccinated and she recommended that they get tested. The governor added that the Anime convention organizers have a complete list of individuals who attended the two-day event, which will simplify contact tracing to identify any potential outbreaks.

“Everyone had to be vaccinated in order to participate in the first place,” Hochul said. “That’s why we anticipate if people who test positive, at least, based on this first individual, that the symptoms will be fairly minor.”

New York City Mayor Bill de Blasio said the city is working closely with the state, the Centers for Disease Control and Prevention, and the convention organizers to contact trace attendees. In a statement Thursday, he urged attendees of the convention, especially those experiencing symptoms, to get tested immediately and take additional protocols such as social distancing.

“We are aware of a case of the Omicron variant identified in Minnesota that is associated with travel to a conference in New York City, and we should assume there is community spread of the variant in our city,” de Blasio said.

Bassett noted that the Wadsworth Center, the state health department’s biodefense lab, is continuing to conduct genomic sequencing to identify the omicron variant.

“It is not a problem that Wadsworth is not performing its job. It is simply that [the variant] has not yet been detected,” Bassett said.

Hochul said she doesn’t plan to impose lockdowns on commerce and schools that had paralyzed much of the state at the beginning of the pandemic, calling it an “overreaction.”

“I will not cause a panic to the people of this state who have already been through so much” Hochul said. “I am not an alarmist. I’m not considering shutting down schools or the economy at this time.”

“Imagine where we would be if we didn’t have the vaccination. Then we would be in a crisis situation,” she said. “I don’t see a return to that as long as the vaccine and the boosters continue to work.”

On Wednesday, the CDC confirmed the first U.S. case of the variant in Northern California. The individual, who was fully vaccinated, had returned to the San Francisco from South Africa on Nov. 22 and tested positive on Nov. 29, White House chief medical advisor Dr. Anthony Fauci told reporters Wednesday.

The U.S. joins at least 23 countries across the world that have confirmed cases of omicron. The variant was first identified in Botswana last month and reported to the World Health Organization by South Africa about a week ago.

Omicron has more than 30 mutations to the spike protein alone, which is the mechanism used by the virus to enter the body. Some of the mutations are associated with higher transmission and a decrease in antibody protection, according to the WHO.