WASHINGTON - The White House projected calm even as it confirmed a breakthrough infection on its own staff Tuesday, sticking to its message that vaccines and safety protocols would keep Americans safe from coronavirus as the Delta variant moves through the country.

White House press secretary Jen Psaki said Tuesday that a fully vaccinated staffer had tested positive for the coronavirus, shortly after House Speaker Nancy Pelosi's office confirmed one of her staff had tested positive.

The Pelosi staffer had contact with Texas lawmakers who are in Washington to prevent passage of a voting bill in their home state. Six members of that delegation have tested positive for the coronavirus in recent days.

Nearly 60 Democrats from the Texas legislature came to Washington earlier this month, using their time out of their home state to try to persuade Congress to pass federal legislation that would supersede efforts from Republicans in Texas to pass restrictive voting laws there. The lawmakers quickly secured meetings with Vice President Kamala Harris, Sen. Joe Manchin III, D-W.Va., and other Washington politicians during their first week on Capitol Hill.

White House press secretary Jen Psaki said the staffer tested positive Monday and remains off-campus awaiting additional tests. The individual did not have close contact with the president or other White House principals or staff, Psaki added.

"We know there will be breakthrough cases, but as this incident shows, cases in vaccinated individuals are typically mild," she said.

Drew Hammill, Pelosi's deputy chief of staff, said the Pelosi staffer has had no contact with the speaker since exposure.

"The entire Press Office is working remotely today with the exception of individuals who have had no exposure to the individual or have had a recent negative test," he said in a statement. "Our office will continue to follow the guidance of the Office of Attending Physician closely."

At a Cabinet meeting Tuesday afternoon, President Joe Biden said Americans "have to stay vigilant, especially with the delta variant that's out there." He made no mention of the recent case in the White House.

"I know folks are watching the number of cases rising again and wondering, quite frankly, what it means to them," Biden said. "But overall, overall, covid-19 deaths are down dramatically, dramatically [over] these last six months."

In addition to mingling with lawmakers from Maryland, Virginia and Georgia at a reception in their honor at a downtown District of Columbia restaurant Wednesday, the Texas Democrats also held a joint news conference in Alexandria, Va.

Some of them had been scheduled to attend a church service hosted by Virginia Del. Luke Torian, a Democrat, on Sunday in Dumfries, Va. The service was canceled Saturday because of the coronavirus outbreak, a Virginia House of Delegates staffer told The Washington Post.

Testing is now underway for people who came into contact with the Texas delegation.

Billy Mitchell, a Georgia state representative and president of the National Black Caucus of State Legislators, hosted a reception for the Texans at a Washington restaurant last Wednesday night. The restaurant prepared for 100 guests, and "the place was packed," Mitchell, a Democrat, said in an interview.

"I'm scheduled to take a test this week, and we are advising all of our members who were there to do the same," he said, adding that he has not heard of any covid cases arising specifically from the event.

Attendees included state legislators from around the country who were in town for an NBCSL leadership retreat and board training, he said.

Del. Darryl Barnes, D-Prince George's, chairman of the Legislative Black Caucus of Maryland, said he was one of five lawmakers from that state who attended the news conference with the Texas lawmakers last week. He said none of his Maryland colleagues have symptoms or have fallen ill but he has asked them and his group's executive director, who also attended, to get tested "out of an abundance of caution."

Barnes said his executive director has been in contact with her counterpart from Texas and was told that all their members who were at the event are being tested daily and none have tested positive.

"The ones that have come down have been their White colleagues," he said. "They are also waiting to see if it is a false positive."

Del. Debra Davis, D-Prince George's, who attended the news conference and a reception, said she had been thinking about getting tested since she learned over the weekend about the positive cases. She said she has been feeling fine but did not know if she was exposed. She also wondered about how often those who are vaccinated get infected.

"My first thought: I'm going back in the bubble," she said.

Chris Turner, chair of the Texas House Democrats, said the outbreak is just the latest example of why getting vaccinated is so important.

"We're seeing breakthrough cases in the vaccinated population . . . and a wide array of professions and parts of the world, and so, it's just, I think, a reminder . . . It's really, really important that we get people vaccinated ASAP," he said during a Tuesday news conference.

But the lawmaker said he does not regret coming to Washington with the goal of bringing national attention to the plight of Texas residents desiring expanded voting rights.

"We don't regret coming to D.C. at all," he said. "It was very important to protect the freedom to vote that we leave Texas. . . . It was equally important that we use this moment to highlight the need for federal voting rights legislation. That's what we have been doing nonstop for the last eight days."

Back in Austin, some GOP state lawmakers said they still wanted their missing colleagues to return - even if they were potentially infected.

"We have the protocols in place - they can still participate in a quarantine status," Texas state Rep. James White, a Republican, said. He added that the outbreak in Washington caused him to talk to his chief of staff about starting to rapid-test staff once again.

Texas state Rep. Briscoe Cain, a Republican, said masks have always been optional in his office.

"Of course, I hope there's no long-term side effects from it," Cain said about the infection among House Democrats. "I don't think they were expecting their trip to D.C. to go viral in the way that it has."

The Washington Post's Ovetta Wiggins, Laura Vozzella in Richmond, Va., and Eva Ruth in Austin, Texas, contributed to this report.