A sign on a Portland shop window advises customers masks are required for entry on Tuesday Dec. 28, 2021. Credit: Troy R. Bennett / BDN

AUGUSTA, Maine — The number of Mainers who have died with COVID-19 surpassed 2,000 on Thursday following a winter surge in the virus driven by highly contagious variants.

Although the Maine Center for Disease Control and Prevention officially reported 53 new deaths on Thursday, all but a few were discovered by a review of vital records and occured in January. Gov. Janet Mills, a Democrat, characterized the toll as an “unwelcome milestone.”

“I ask all Maine people to join me in remembering those we have lost, honoring their lives, and doing what we can to prevent more illness and death, most especially by getting vaccinated,” she said.

It comes as several key indicators suggest COVID-19 is declining in Maine. But it also reflects the widespread impact the virus has had since March 2020 — particularly in the past few months — with older Mainers and those who are unvaccinated most affected.

Here is what the data say about where we are and where we are going.

It took 18 months to reach 1,000 COVID-19 deaths. It took less than six months to reach 2,000.

Maine surpassed 1,000 COVID-19 deaths in mid-September 2021 — nearly 18 months to the day after the virus was first detected here. The state then saw 1,000 more deaths in less than six months.

A driving factor for the higher death rate was the arrival of the highly contagious delta variant, which was first detected in Maine in July and dominated cases into the fall until it was largely replaced by the even more contagious — though less deadly — omicron strain.

After dropping to low levels the previous summer, virus deaths rose sharply in August. Unlike previous surges of the virus headed off by aggressive distancing or vaccines, the delta variant persisted, with record deaths coming in December 2021, despite Maine’s high vaccination rate.

But the delta variant was displaced by the even more contagious omicron strain, which became predominant in January. While cases skyrocketed with the highly transmissible variant, severe cases did not. Deaths dropped slightly from December to January. February deaths look to be much lower, though the month is not yet complete.

Vaccinations have substantially reduced deaths.

Since May 2021, when all Maine adults were eligible to become fully vaccinated, about 830 unvaccinated Mainers have died with COVID-19. By contrast, just shy of 360 fully vaccinated Mainers — a much larger population — have died.

Counties with lower vaccination rates have higher death rates. Since May, the most highly vaccinated county — Cumberland County, where roughly 84 percent of people are fully vaccinated — has the lowest COVID-19 death rate in Maine, with 4.7 deaths per 10,000 people. The counties with the highest death rates over that time period — Androscoggin, Franklin, Penobscot and Somerset — all have vaccination rates lower than 67 percent.

Older Mainers still face the highest COVID-19 risk, but deaths among young people increased most in the pandemic’s second year.

About 86 percent of total COVID-19 deaths have been among Mainers aged 60 and older. But deaths among younger people increased by a greater percentage in the past year. That likely reflects lower vaccination rates — while 95 percent of Mainers aged 70 and older are fully vaccinated, only 72 percent of Mainers in their 20s and 30s are, according to state data.

While no children younger than 20 died in the first year of the pandemic in Maine, three have died since June 2021. Only three Mainers in their 20s or 30s died from the virus through May 2021. But 27 have died since then, according to state data.

If Maine matched the U.S. average, nearly 2,000 more people would have died.

Despite being the oldest state in the nation, Maine has the fourth-lowest death rate of any U.S. state, with only Hawaii, Vermont and Utah seeing lower death rates, according to the New York Times.

Maine has recorded 147 COVID-19 deaths per 100,000 people since the start of the pandemic compared with 283 deaths per 100,000 people across the U.S. If Maine’s death rate was in line with that figure, the state would have recorded just shy of 3,900 virus deaths at this point.

On the flip side, if the rest of the U.S. had Maine’s COVID-19 death rate, virus deaths across the nation would total around only 485,000 — rather than nearly 1 million.