As the delta variant spreads rapidly in the United States, officials announced Tuesday that multiple Congressional and White House staffers, as well as at least one member of Congress, have tested positive for the coronavirus—despite being vaccinated.

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Delta variant makes its way to DC

CDC Director Rochelle Walensky on Tuesday said the delta variant now accounts for an estimated 83% of all new U.S. coronavirus cases, marking a "dramatic increase" since early July, when it accounted for just over 50% of new cases.

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Meanwhile, officials told Axios that a White House official and a staff member in the office of House Speaker Nancy Pelosi (D-Calif.) both tested positive for Covid-19 after attending the same reception last week. Both people had been fully vaccinated and are experiencing mild symptoms, Axios reports.

In a statement, a White House official said, "In accordance with our rigorous Covid-19 protocols, the official remains off campus as they wait for a confirmatory PCR test. The White House Medical Unit has conducted contact tracing interviews and determined no close contacts among White House principals and staff. The individual has mild symptoms."

White House Press Secretary Jen Psaki confirmed in a press briefing that the official tested positive for Covid-19 on Tuesday. She added that there have been multiple breakthrough infections among vaccinated staff in the White House, but she emphasized that symptoms are "typically mild" in vaccinated individuals.

In addition, Rep. Vern Buchanan (R-Fla.) announced Monday that he had tested positive for the coronavirus after being fully vaccinated, marking the first known member of Congress this summer to test positive for the virus.

Brian Monahan, the attending physician of Congress, said Tuesday that several "Congressional staff members and one member of Congress have acquired infection" with the coronavirus after being vaccinated.

In response to rising infection rates nationwide, House Majority Leader Steny Hoyer (D-Md.) said Congress may reconsider its mask-wearing policy.

"Now we're not wearing the masks," Hoyer said. "We're going to have to decide whether or not—given the upswing in every state—whether or not prudence demands that we go back to wearing masks."

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Senate Minority Leader Mitch McConnell (R-Ky.) on Tuesday encouraged Americans to get vaccinated as soon as they can.

"These shots need to get in everybody's arm as rapidly as possible, or we're going to be back in a situation in the fall—that we don't yearn for—that we went through last year," he said.

Rep. Steve Scalise (R-La.) on Sunday received his Covid-19 vaccine, citing the spread of the delta variant for his decision.

"Especially with the delta variant becoming a lot more aggressive and seeing another spike, it was a good time to do it," he said.

Chicago implements travel advisory

Meanwhile, Chicago on Tuesday added three states and one U.S. territory to the city's Covid-19 travel advisory.

Any unvaccinated travelers from Florida, Louisiana, Nevada, or the U.S. Virgin Islands are being advised to get a negative Covid-19 test no more than 72 hours before traveling to Chicago, or to quarantine for 10 days upon arrival, the Chicago Department of Health said.

The city added Missouri and Arkansas to its travel advisory last week after the states surpassed the city's threshold of 15 Covid-19 cases per 100,000 residents.

"We remain well below our peak rates, but these recent increases are concerning," Allison Arwady, commissioner of the Chicago Department of Health, said in a statement. (Stolberg, New York Times, 7/20; Nichols, Axios, 7/20; Gonzalez, Axios, 7/20; Wise, NPR, 7/20; Treene, Axios, 7/20; Walsh, Axios, 7/21)