WASHINGTON – The House of Representatives has been ordered by the resident physician on Capitol Hill to mask up once again as fears of the highly contagious delta variant of the coronavirus spreads rapidly across the country.

In a late evening email sent to all offices in Congress on Tuesday, the Office of the Attending Physician Dr. Brian Monahan reinstituted a mask mandate in all House office buildings, meeting areas and the chamber to prevent the spread among members and staff.

While he suggested that “well-fitted, medical-grade filtration” masks be worn in the Senate, Monahan stressed the immediate requirement of use on the opposite side of the Capitol Dome given the “collection of individuals traveling weekly from various risks.” Masks, however, are not required when an individual is alone inside a room or outside.

The order came after the Centers for Disease Control issued new recommendations for mask use Tuesday, urging all vaccinated and unvaccinated individuals to wear a mask indoors if they live in areas with high spread of the delta variant.

It immediately revived a debate among members on Capitol Hill about the need to follow the rules again, with Republicans accusing Democrats of trying to infringe on freedom of choice.

“Make no mistake – The threat of bringing masks back is not a decision based on science, but a decision conjured up by liberal government officials who want to continue to live in a perpetual pandemic state,” Minority Leader Kevin McCarthy, R-Calif., tweeted shortly after Monahan sent his email.

Democrats, however, dismiss the big-government accusations, with most personally choosing to take proactive steps before Monahan issued his memo Tuesday. Members and staff were seen wearing masks around the Capitol after six state Texas Democratic lawmakers became infected with the virus that spread to a senior spokesperson for Pelosi who was fully vaccinated last week. The on-site testing facility on Capitol Hill has also seen a significant uptick of visitors requesting a coronavirus test, extending their hours to accommodate the demand.

It’s unclear whether Republicans will follow the new rules, but one incentive to do so is Monahan’s threat that members will be fined if they do not wear a mask on the floor. Before the CDC repealed the mask mandate nationwide for vaccinated individuals in May, Rep. Marjorie Taylor Greene, R-Ga., and other fervent pro-Trump Republicans boycotted the rule by taking pictures of themselves maskless on the House floor, incurring fines.

Greene; Rep. Thomas Massie, R-Ky.; and Rep. Ralph Norman, R-S.C., filed a lawsuit in U.S. District Court against Speaker Nancy Pelosi, D-Calif., over their fines, arguing that it violates the 27th Amendment since the penalty is taken from their paychecks.

Even so, Republicans have increased their calls for supporters to get vaccinated amid the spread of the delta variant, which is spreading at a higher rate in some GOP-led states. Senate Minority Leader Mitch McConnell, R-Ky., last week urged Americans “to ignore all of these other voices that are giving demonstrably bad advice” about not getting vaccinated, but expressed skepticism to masking up in the Senate noting the “environment right here is pretty safe.”

McConnell, who was vaccinated in December and has been promoting vaccinations in public remarks ever since, plans to run 60-second radio ads on more than 100 Kentucky radio stations in coming days promoting the vaccine with money from his reelection campaign, McConnell spokesman Doug Andres tweeted on Wednesday.

Frustration about Republicans has emerged among Democrats on Capitol Hill, who blame them for the need to mask-up again, given that a majority of House conservatives have apparently not received the coronavirus vaccine. A survey of all 535 members of Congress by CNN found that in May, 100% of Democrats from both chambers were fully vaccinated, while only 44.8% of House Republicans and 92% of Republican senators said the same. Democrats say the lag in vaccinations among conservatives has been holding them back in easing restrictions on Capitol Hill.

In recent days, Republicans have argued that they do not need to disclose their vaccination status, arguing that even asking about is a violation of the health privacy law, HIPPA. Monahan, however, writes that any unvaccinated person should come to his office to receive a vaccine.

“For those individuals reliant upon recovery from natural infection, the Delta variant is a severe threat and recovery from previous infection provides little or no protection against the coronavirus variants,” he warned.