Gov. Ned Lamont of Connecticut, a Democrat, has tested positive for the coronavirus, his office announced on Thursday.
His office said on Thursday afternoon that a rapid test Mr. Lamont took showed a positive diagnosis, which was later confirmed with a second rapid self-test. Mr. Lamont was waiting for the results of a P.C.R. test.
The governor, 68, received a second booster shot on March 31, after federal health officials cleared the extra boosters earlier in the week for those 50 or older, among other groups. It takes about a week for the immune system to ramp up, and it is difficult to know exactly how someone was exposed to and infected with the virus.
“I see some noise going over there in Britain, why not err on the side of caution and do this again?” Mr. Lamont said then, referring to the surge of new cases in Britain, while getting the additional booster. “I feel really good. I’ll be safe at least for the next six months.”
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.”