Congress’ doctor said his office is expanding Capitol testing and called for wearing more robust masks as “dozens” of daily samples from the Capitol testing site are coming back positive for COVID-19.

The Office of the Attending Physician announced the Capitol COVID-19 testing center’s seven-day positivity “rate went from less than 1 percent to greater than 13 percent.” Positive tests at the Capitol reflect what is happening in the Washington area, as the city in the last week has posted its highest infection rates of the pandemic.

In internal Dear Colleague letters to the Capitol community Monday, Attending Physician Brian P. Monahan said House and Senate offices should adopt “maximal telework” to reduce in-person contact, and that blue surgical masks, cloth face masks and gaiter masks “must be replaced by the more protective KN95 or N95 masks.” He also said the Capitol Visitor Center test center’s space and personnel are in the process of being expanded.

Testing on a limited number of samples found that the omicron variant of COVID-19 represented about 61 percent of cases and delta variant made up 38 percent of positive cases. The OAP memo said 65 percent of the people who tested positive were displaying symptoms.

The weekly case rate per 100,000 people in Washington was 1,904.9 on Monday, according to the DC Health website. Last month that number was 70.

At least a dozen lawmakers have announced they tested positive since late December, but it is possible the number could be even higher — members of Congress are under no obligation to publicly say they have tested positive.

Inches of snow fell on Washington Monday morning, scuttling plans for an evening vote in the Senate and causing closures across the city. The chamber briefly met at noon to convene the second session of the 117th Congress and delayed a 5:30 p.m. vote until noon Tuesday, before party lunches.

Unlike the House, the Senate side of the Capitol has not imposed mask mandates. Past guidance to Senate-dwellers has been to strongly encourage mask-wearing, but not go as far as a mandate.

Senate Democrats are expected to hold virtual caucus lunches at least this week, according to a Senate Democratic source familiar with their plans. The GOP has not yet announced changes to its in-person lunches.

Although the House briefly met Monday to convene the second session of the 117th Congress, members are not scheduled to be back until next week. Some members will be around to commemorate last year’s Jan. 6 attack on the Capitol. President Joe Biden and Vice President Kamala Harris will give speeches Wednesday morning in Statuary Hall about the attack, and Thursday will feature events on the House side to mark the attack, including member testimonials in person and virtually in the Cannon Caucus Room.

Next week will feature more remembrance: Former House Majority Leader Harry Reid, who died late last month, will lie in state in the Capitol Rotunda on Jan. 12th.

Those events, along with most public tours — except for small staff-led tours on the Senate side of the Capitol — will be not open to the public because of the pandemic and security issues.

Most cases among members and staff were “breakthrough” infections contracted by those who have already received vaccinations, Monahan’s letter said. The cases have not led to hospitalizations, serious complications or deaths, “attesting to the value of coronavirus vaccinations,” the letter said.

“Any group activity indoors should promote strict mask-wear compliance,” the letter said.

Last week a couple of House-side eateries closed temporarily due to rising numbers of COVID-19 cases among staff.

The Office of the Chief Administrative Officer announced that some House-side food service options would be closed this week, and the offerings that do remain open will be takeout-only to reduce the risk of spread at mealtime.

The OAP did not release specific numbers on how many people have tested positive at its site. Monahan said his office had administered 7,500 booster vaccinations to Capitol personnel and encouraged those who have not been vaccinated or gotten their booster shot to do so.

“Individuals previously relying on recovery of natural infection should receive coronavirus vaccination at the earliest opportunity,” the letter said.