Maine shattered its daily record with 551 new cases of COVID-19 reported Wednesday, just one day after front-line health care workers received the first vaccines in Maine.

Wednesday’s surge marked the first time cases have topped 500 and comes less than two weeks after Maine first cleared 400 daily cases, with 425 on Dec. 6.

“We are squarely seeing the effects of (COVID-19) transmission that occurred in and around Thanksgiving. Case numbers are going up and up and up,” Dr. Nirav Shah, director of the Maine Center for Disease Control and Prevention, said during a media briefing Wednesday. “It’s not just Maine, it’s occurring across the country.”

While case numbers continue to reach unprecedented levels, there has been positive news this week with the beginning of vaccination efforts. At least 720 nurses, doctors and other health care workers at hospitals across Maine who are at highest risk for exposure to COVID-19 had been inoculated by late afternoon Wednesday – and thousands more are set to join them in the coming weeks.

But it will take months before vaccines have an impact on COVID-19 spread, Shah said.

“There will be cases of COVID-19 that persist even after vaccinations have begun in earnest,” he said, adding that the end of the pandemic is like a “very long tail,” and the virus will continue to circulate, although hopefully cases will decline in 2021. It may take half the population to get vaccinated before case rates decline significantly.

Shah said he’s concerned about the upcoming holiday season and the prospect of people gathering with family and friends outside their homes.

“If staying home, staying in your pod or in your bubble is something that’s available to you, that’s definitely the most helpful thing you can do this winter,” he said.

The seven-day daily average of COVID-19 cases in Maine increased to 409.3 on Wednesday, compared to 329.7 a week ago and 177.3 a month ago. It took only one week for the seven-day average to increase from 300 cases to more than 400 cases. The jump from 200 cases – first seen on Nov. 2 – to 300 cases took about two and a half weeks. New cases were reported in every Maine county, led by Cumberland County with 147 and York County with 146.

Just since Monday, the Maine CDC has opened several outbreak investigations, including at four schools, a hair salon in Norway, the Newport Town Office and the Cumberland County Jail. An outbreak at York Hospital has grown to 36 staff members and 14 patients.

A pedestrian walks past a store in the Old Port on Dec. 11. Gov. Janet Mills signed an executive order that day requiring businesses and public spaces of any size and for any number of people to mandate mask wearing. Shawn Patrick Ouellette/Staff Photographer

The Maine CDC also reported two additional deaths Wednesday: woman in her 80s from Androscoggin County and a man in his 80s from Oxford County.

Since the pandemic began, Maine has recorded 17,311 confirmed or probable cases of COVID-19 and 267 deaths. Total cases have doubled in a little more than a month. The number of deaths just this month increased to 50 and is on pace to eclipse last month’s total of 67, which was the highest to date.

Hospitalizations remain high as well, although the number did decrease by eight on Wednesday. There are currently 187 individuals in the hospital with COVID-19, including 46 in critical care and 18 on ventilators. Shah said there are still enough hospital beds to handle a surge, but it’s something officials monitor closely.

On Tuesday morning, Maine Medical Center nurse Kayla Mitchell became the first person in Maine to receive the COVID-19 vaccine. Thousands more health care workers will follow in the coming days.

At Central Maine Medical Center in Lewiston, Dr. Claudia Geyer was one of the first to be vaccinated, and she pleaded with people to stop gathering with others outside of immediate family, even for Christmas.

“COVID is so real and so devastating,” Geyer said, noting that most of the COVID patients they are treating attended gatherings over the Thanksgiving holiday weekend. “Please remember that. We said that would happen and here it is. And Christmas is around the corner.

“We’re so afraid that, again, in mid-January our unit will be filled with people who just wanted to be with their family for Christmas.”

Maine is expected to get about 75,000 doses of both the Pfizer and Moderna vaccines by the end of December, with production and distribution of the vaccines ramping up in 2021. It’s difficult to predict when the vaccine will be widely available to the general public, but that could occur in the spring or early summer, public health experts say, depending on how smoothly the distribution and mass immunization programs go.

Meanwhile, dentists and dental hygienists are volunteering to be part of the group that vaccinates the general public once vaccine supplies become more plentiful in 2021. Shah said both groups and others will “absolutely” be considered to be part of the vaccinating team.

“We’re considering offers from members of the dental community, retired pharmacists, nursing students, medical students all those different vaccinator groups,” Shah said on Wednesday.

Sun Journal Staff Writer Lindsay Tice contributed to this report.