The number of people hospitalized with COVID-19 in Maine remained high on Sunday, the state reported.

According to the Maine Center for Disease Control and Prevention, 415 patients were being treated for the infectious disease in hospitals statewide. Of those, 109 were in critical care units and 56 on ventilators.

The number of patients was down slightly from Saturday’s 418, and from the pandemic high of 436 inpatients on Thursday. However, the numbers are more than double what they were a year ago, when the winter peak of those hospitalized with COVID-19 was near 200. The number of sick patients continues to overwhelm medical resources, to the point that National Guard troops are being deployed to help medical facilities across the state.

The majority of patients hospitalized with COVID-19 are unvaccinated, doctors have said. Southern Maine hospitals are seeing the biggest surge of patients because the highly contagious omicron variant is quickly infecting more populated parts of Maine.

With omicron, people who are fully vaccinated and boosted are getting infected with COVID-19, but in most cases the vaccines keep them from getting so sick they need to be hospitalized. With omicron, experts are urging everyone, including the vaccinated and those with booster shots, to mask up in public, indoor spaces and crowded indoor spaces.

Dr. Tom Frieden, an infectious diseases expert and former head of the U.S. Centers for Disease Control and Prevention under President Barack Obama, said in a tweet Friday that a stunning number of people in the United States have omicron, that “it’s stunningly transmissible and has left delta in the dust. … We’re diagnosing 1 million a day, and likely missing three to five times that many. People are potentially infectious for around five days.”

In the past two months much has been learned about omicron, Frieden said.  In people who are vaccinated and with boosters, omicron is far less likely than delta to cause severe disease, and it appears the current spike driven by omicron may subside as quickly as it rose, like what happened in South Africa, he said.

“But we’re far from out of the woods,” Frieden said. “Rapid increases in cases are leading to increases in hospitalizations, ICU admissions and deaths, especially among the unvaccinated.” That, he warned, may continue for several weeks.

According to the Maine CDC, 72.18 percent of all Mainers are fully vaccinated.

Out of Maine’s population of 1.34 million, 970,248 Mainers have received their final vaccination. That number includes 32,545 of the youngest set able to be vaccinated, ages 5-11.

And the number of those with booster shots, has gone up to 528,058, according to the state.

While Maine continues to see its highest caseload and death toll of the pandemic, there are glimmers of hope: The number of patients in critical care units has stabilized even while cases continue to spike.

Meanwhile, the national federal CDC has conceded that cloth face masks do a poor job protecting wearers from being infected from the omicron variant, and is now recommending more protective masking such as the KN-95 or the N-95, especially in public, indoor spaces as well as outdoor spaces that are crowded.

The total number of cases in Maine since the pandemic began numbers 160,857.  Many of the new reported cases are from tests submitted days earlier since there’s a significant backlog of tests, and many individuals are testing positive with at-home tests, and those results aren’t always reported to state officials.

Since the pandemic began, a total of 1,658 people in Maine have died with COVID-19, the state reported Saturday.