On Thursday, he said on Twitter that he felt good and was not experiencing any symptoms.
“We’ve done contact tracing to let people know,” he said. “Thankfully I’m double boosted and I encourage everyone to get your vaccine and boosters if eligible.”
Mr. Lamont said that he will isolate at home for the next five days and not attend any in-person events or meetings.
The highly transmissible Omicron subvariant known as BA.2 has become the dominant version among new U.S. cases, four months after it was first detected in the country. The Centers for Disease Control and Prevention estimated on Tuesday that BA.2 accounted for about 72 percent of new U.S. cases in the week that ended April 2.
As of Wednesday, an average of 489 new virus cases per day were reported in Connecticut in the previous week. New cases have increased by 56 percent over the last two weeks, according to a New York Times database.
Last month, Mr. Lamont urged Connecticut residents to order rapid tests at covidtests.gov. “With the BA.2 Covid variant spreading across the nation, Connecticut is ready,” Lamont wrote in a tweet. “Families have layers of protection available — vaccines + boosters, quality masks, and at-home rapid testing.”