COVID-19 was the eighth-leading cause of death in Maine in 2020, and it played a substantial role in driving up the number of total deaths by 4.5 percent.

But the highly infectious disease was a much graver threat across the nation, ranking third as a cause of death in the U.S. as a whole and increasing the number of total deaths by 16 percent.

The contrasts reflect the impact of Maine’s comparatively rapid and aggressive response to the virus with masking, social distancing standards, restrictions on gatherings and other protective steps that curbed infections and deaths even though the state has the oldest population in the nation.

“A year ago, I was very worried because of the age (of the populace) of our state, and looking at the mortality trends for COVID-19, and I thought, ‘Oh no, this is going to be horrible for Maine,'” said Dr. Laura Blaisdell, a pediatrician and infectious-disease expert from South Portland. “But we did something right in terms of public health. We tried to keep our infections exceedingly low until we got a vaccine. I think of it as a public health success story.”

Deaths from all causes in Maine rose from 15,068 in 2019 to to 15,749 last year. That’s an increase of 681 deaths, and the 422 lives taken by COVID-19 account for 62 percent of them, according to preliminary data from the Maine Center for Disease Control and Prevention. The virus was a contributing factor in 56 other deaths.

Cancer and heart disease remained the top two causes of death in Maine, followed by accidents, lower respiratory diseases, strokes, Alzheimer’s disease, diabetes and then COVID-19.

The national death toll last year was 378,000, and that figure had climbed to more than 560,000 through April 21. In Maine, total COVID-19 deaths since the pandemic began were at 768 through April 21, slightly more than a year into the pandemic.

The low numbers of COVID-19 cases in Maine translated into fewer deaths in comparison to most of the rest of the country. If Maine had experienced the average death rate of the nation, the state would have logged at least three times as many deaths in 2020, about 1,300 deaths instead of 422, according to a comparison of state and federal statistics. Only three states had fewer deaths per capita than Maine – Alaska, Vermont and Hawaii.

The other leading causes of death for 2020 in Maine were unchanged from recent years, with cancer the No. 1 cause of death, claiming 3,434 lives, and heart disease at 3,034, the second-leading cause of death. The third-leading cause of death, accidental deaths, increased from 1,025 in 2019 to 1,144 in 2020, spurred by a record high 502 drug overdose deaths, which are included in the accidental death category.

“When we look at the leading causes of death from 2019 to 2020, the top seven leading causes of death (in Maine) remain the same from 2019 to 2020,” said Dr. Carolyn Bancroft, an epidemiologist who works in vital statistics for the Maine CDC.

Dr. James Jarvis, Northern Light Health’s COVID-19 incident commander, said too many deaths have been caused by COVID-19, but the results would be even worse had the state not imposed restrictions and required mask wearing and other measures to contain transmission.

“People stood up and started wearing their face coverings early on and limited gatherings,” he said.

Maine’s deaths increased 4.5 percent from 2019 to last year, according to preliminary data. Nationally, deaths jumped by 16 percent in 2020. The age-adjusted death rate per 100,000 people in Maine increased from 759.7 in 2019 to 793.8 in 2020, according to federal and state statistics. The data is adjusted for age for better comparisons among states, so that states like Maine with older populations can be compared to states with a younger average age.

“We’ve been fortunate,” said Dr. Dora Anne Mills, chief health improvement officer for MaineHealth, the parent company of Maine Medical Center. “We’ve had such relatively low rates of COVID in Maine despite having the oldest population in the nation.”

As for why Maine’s death rates were lower, Dr. John Alexander, chief medical officer for Central Maine Healthcare in Lewiston, said, “Certainly geography has played an important role, as has the adherence to public health guidelines regarding mask wearing, hand hygiene and social distancing.”

The pandemic was more severe in urban, coastal parts of the country at the beginning of the pandemic, before spreading to rural areas, according to research published in January in the Proceedings of the National Academies of Sciences.

Maine is one of the most rural states in the nation, and Mills pointed out that the state is also bordered by Canada and the ocean, perhaps protecting Maine from COVID-19 more than other states, because the Canadian border has largely been closed since last spring.

Rachael Piltch-Loeb, a public health emergency preparedness expert at Harvard University, said some states, such as Maine and Vermont, imposed pandemic restrictions before people had contact with the virus, buying those states time while the pandemic worsened elsewhere.

There are other differences between Maine and the country in terms of how people die. In the U.S., heart disease is the leading cause of death, but in Maine, cancer is the No. 1 cause.

“We don’t know the exact reason, but we do know consistently Maine has a high cancer mortality rate,” Bancroft said. “Smoking, occupational risk factors, environmental risk factors like radon and arsenic, all are a number of different potential reasons why our cancer mortality is higher.”

Radon gas in homes can lead to elevated risks of lung cancer, and arsenic in well water has also been associated with increased cancer risks in Maine. The 2020 cause of death data is still preliminary, but Maine CDC officials believe more than 95 percent of the state data is in.

Meanwhile, births continued to decline, with 11,534 births in 2020, a decline of 238 from 2019, when there were 11,772 births. That’s in line with national trends that saw decreased births during the pandemic. However, the gap between births and deaths widened in Maine in 2020, with 4,215 more deaths than births, compared to 3,296 more deaths than births in 2019.