Maine hospitals are reporting a steep spike in staff absences caused by COVID-19, raising staffing concerns at the same time the percentage of positive COVID-19 tests has nearly doubled in two weeks and hospitalizations have returned to a near-record level.

Dr. Nirav Shah, the director of the Maine Center for Disease Control and Prevention, said all indications are that the omicron variant is “well established” in Maine despite official sequencing reports showing it represents only 8.75 percent of cases. The sequencing report lags by about two weeks, which means the report released Monday analyzed results from Dec. 19-25.

“We know this is an undercount, indeed likely a dramatic undercount,” Shah said during a media briefing Wednesday.

Other countries, such as the United Kingdom and South Africa, saw a rapid rise in omicron cases followed by a dramatic decline.

“The question for omicron is whether the graph of cases it generates will look like a giant wave like the delta variant, or like a sharp icicle, rising very quickly and then falling very quickly,” Shah said.

Maine’s PCR test positivity rate has increased to 18.05 percent, the highest rate of the pandemic and a further indication of omicron’s spread. But Shah said the way people are using PCR tests, sometimes as a confirmatory test to a positive rapid test, and the rise of at-home tests, makes it difficult to compare current positivity rates to other times during the pandemic.

“When my team and I look at positivity rate, we look at it how it compares to one or two incubation periods ago, not one or two years ago,” Shah said.

Two weeks ago, or one incubation period, the state’s PCR positivity rate was 9.6 percent. PCR tests are considered the “gold standard” but typically take longer to produce results when compared to a rapid antigen test.

Even though Maine’s positivity rate is the highest it has ever been, many states are seeing even higher rates as omicron spreads rapidly.

The U.S. CDC tracks state-by-state data, but positivity rates are often estimates, and because states vary widely with testing volume, comparisons can be challenging. But according to the most recent seven-day period, 24 states have positivity rates that exceed 25 percent. Maine is one of 10 states with a positivity rate between 15-20 percent.

In addition to the rapid spread of new transmissions, hospitalizations remain high. Maine reported 382 hospitalizations statewide on Wednesday, up from 373 on Tuesday and close to the pandemic high point of 387 set on Dec. 21. Of those currently hospitalized, 117 patients are in critical care and 59 are on ventilators. Shah said 70 percent of those hospitalized in Maine are unvaccinated.

ABSENCES PUT STRAIN ON HOSPITALS

The state’s two largest hospital systems are increasingly seeing staff members infected, which is putting strain on an already overburdened health care system.

At Northern Light Health, hospital officials said 493 employees out of the 12,000 workers systemwide are either out sick with COVID-19 or quarantining at home while awaiting the results of a COVID-19 test.

Paul Bolin, senior vice president at Northern Light Health, said the number out sick is an “all-time high” during the pandemic, and they hope it doesn’t continue to increase. While health care workers are required to be vaccinated, the omicron variant is more likely to evade vaccines and cause illness. However, the vaccines are still highly effective at preventing serious illness, hospitalization and death, public health experts have said.

MaineHealth, the parent organization of Maine Medical Center in Portland and seven other Maine hospitals, reported Wednesday that staff absences caused by COVID-19 were at the highest point since vaccines became available, increasing more than fourfold over what they had been before Christmas.

“The surge is likely caused by the arrival of the highly contagious omicron variant in Maine and New Hampshire, and the result is that 842 members of MaineHealth’s care team of about 22,000 were unable to come in to work as of this morning due to COVID-19,” MaineHealth said in a news release Wednesday. “Prior to the Christmas holiday, about 200 people per day were absent across the health system because they had contracted or had been exposed to COVID-19.”

MaineHealth has not requested assistance from the administration of Gov. Janet Mills or the federal government to fill the staffing void, said John Porter, the health care network’s spokesman. Mills’ office did not respond to an email Wednesday night asking if the governor was seeking federal help or considering activating Maine Army National Guard troops to assist hospitals if they face a staffing crisis.

Dr. Doug Sawyer, interim chief medical officer at MaineHealth, said in a statement that health care workers are “exhausted, and the overall health care system is under tremendous stress.”

“We need help from our community,” Sawyer said. “We’ve set up booster vaccine clinics this week at our location on Free Street in Portland and at other facilities across our system. We strongly encourage everyone who is eligible to get vaccinated and boosted.”

Hospitals across the country are reporting staffing shortages as well, including in California, Florida and Utah, The Associated Press reported.

Maine reported 1,326 cases of COVID-19 on Wednesday, and 26 additional deaths, although all but one of those deaths was detected by a review of death certificates and occurred in December.

Since the pandemic began, Maine has logged 149,543 confirmed or probable cases of COVID-19, and 1,582 deaths. The case count is increasingly becoming less reliable as a public health metric, experts say, because of the number of people taking at-home tests, which are not included in the case count.

TESTING IN SHORT SUPPLY

Shah acknowledged that testing is in short supply, and the state will be setting up a testing site next week at the Augusta Armory, with details to be released later.

He also said that while case counts are still important, “hospitalizations are a better marker” of where Maine and the United States currently are at in the pandemic, including overall hospitalizations and how many need intensive care and are on ventilators.

Nationally, cases continue to soar with omicron now representing 95 percent of cases nationwide, according to U.S. CDC estimates. However, based on what other countries who have experienced omicron before the U.S., while hospitalizations may increase, the average hospitalized patient may have less severe disease. Intensive care admissions, for instance, remained flat or even declined slightly in the U.K. and Ireland during the omicron surge. Cases in the U.K. and South Africa have started to decline after an intense ramp up.

On the vaccination front, 71.5 percent of Maine’s 1.3 million residents are fully vaccinated, and 36 percent have received booster shots.

MaineHealth is hosting a vaccination clinic at its offices at 110 Free St. in Portland, by appointment only, with hours from  8 a.m. to 3 p.m., on Thursday and Friday. First- and second-dose appointments are available to anyone 5 and older, and booster shots are available for those 12 and older. The clinic has the Pfizer, Moderna and J&J vaccines. To schedule an appointment, go to vaccine.mainehealth.org.

Also, Northern Light Health has reopened its walk-in vaccination clinic at the former Pier One store at the Maine Mall in South Portland. Walk-ins can stop by for a vaccine from 1-7 p.m. on Thursday and 9 a.m. to 2 p.m. on Saturday.

MaineHealth officials also said on Wednesday that people seeking COVID-19 tests should not show up at hospital emergency departments, urgent care centers or walk-in clinics looking for tests. For COVID-19 related or other symptoms, the facilities are to be used for people who have trouble breathing, persistent pain or pressure in the chest, new confusion, inability to wake up or stay awake or with bluish lips or face.

To find testing sites, go to maine.gov/covid19/testing.

Staff Writer Dennis Hoey contributed to this report.