Photo taken on May 29, 2019 shows the US Department of Justice headquarters building in Washington, D.C., the United States. (Xinhua/Liu Jie)

At least two senior US officials and two congressmen have tested positive for COVID-19 after attending a white-tie dinner over the past weekend.

The US Department of Justice announced in a statement Wednesday afternoon that Attorney General Merrick Garland tested positive for COVID-19 through antigen tests.

Garland, fully vaccinated and boosted, asked to be tested after learning that he may have been exposed to the virus. At the time, he is not experiencing symptoms.

The statement also said Garland will isolate at home for at least five days and will return to the office following a negative test for coronavirus.

The positive test result came just hours after Garland spoke in person at a press conference alongside FBI Director Christopher Wray and other federal law enforcement officials.

Garland reportedly went to the Gridiron Club and Foundation dinner on Saturday night - typically one of the most high-profile annual Washington media events.

US Commerce Secretary Gina Raimondo, who also attended the event, is quarantined at home after experiencing mild symptoms and testing positive for COVID-19.

Congressmen Adam Schiff and Joaquin Castro - two other attendees - made public their infections on Tuesday.

The Gridiron dinner is said to have hosted more than 600 government officials, members of Congress, diplomats, and media figures at the four-star Renaissance Hotel in downtown Washington DC.

The annual event, which has been held in various forms for more than a century, was canceled in 2020 and 2021 because of the COVID-19 pandemic.

The total number of COVID-19 cases in the US has exceeded 80 million, with 980,000 related deaths, according to the latest data from Johns Hopkins University.

White House Press Secretary Jen Psaki told reporters that the COVID-19 pandemic "is not over" and warned against the highly contagious Omicron subvariant BA.2 - now the dominant strain of COVID-19 in the US.

"We know BA.2 is here," Psaki said. 

"We know that it is more transmissible."

Biden did not attend the dinner, but he has been present at several crowded events in recent days, where few guests wore masks.

The 79-year-old president received a negative test Monday, the White House said, a week after getting his second COVID-19 booster.

Vice President Kamala Harris, however, may have been exposed recently to COVID-19, with her office reporting that her communications director tested positive after being in "close" contact with Harris.

The vice president, who is vaccinated, "will follow [US health authority] guidelines" and plans to "continue with her public schedule," her spokeswoman said.

Agencies