Life expectancy in the United States dropped by a year and a half in 2020 — a continuation of a worrisome decline that was observed in the first half of last year as the coronavirus pandemic ravaged the country, according to federal data released Wednesday.

The decline, which is the largest seen in a single year since World War II, reflects the pandemic’s sustained toll on Americans, particularly the disproportionate impact of covid-19 on communities of color. Black Americans lost 2.9 years of life expectancy while Latinos, who have longer life expectancy than non-Hispanic Blacks or Whites, saw a drop of three years. There was a decrease of 1.2 years among White people.

“It’s horrific,” said Anne Case, a professor emeritus of economics and public affairs at Princeton University. “It’s not entirely unexpected given what we have already seen about mortality rates as the year went on, but that still doesn’t stop it from being just horrific, especially for non-Hispanic Blacks and for Hispanics.”

The provisional data from the National Center for Health Statistics (NCHS), a part of the Centers for Disease Control and Prevention, shows that life expectancy at birth — a generally reliable measure of the nation’s health — for the total population declined from 78.8 years in 2019 to 77.3 years in 2020. Almost three-fourths of that decline is attributed to deaths from covid-19, according to the report. The report did not include data for Asian Americans or other racial groups.

Lead author Elizabeth Arias, a health scientist at the National Center for Health Statistics, said mortality tends to be fairly stable from year to year, which is why 2020 was “very unusual.”

“From 1943 till now, the changes in life expectancy annually have been very small,” she said.

The drop in life expectancy also reflects the pandemic’s broader impacts on health, including a record-high number of deaths from drug overdoses. In 2020, there were more than 93,000 overdose deaths — a staggering increase largely driven by opioids, primarily illegal fentanyl, though deaths from methamphetamine and cocaine also rose. According to the NCHS, an estimated 11 percent of the decline in life expectancy is due to increases in deaths from accidents and unintentional injuries, and more than one-third of all unintentional injury deaths were drug overdoses.

“There are other festering problems going on here,” Case said. “The one that’s most obvious would be the drug overdose epidemic that continues to blaze.”

Other contributing causes of death include homicide, diabetes, and chronic liver disease and cirrhosis, the report noted. All told, the numbers tell a “pretty dark story about what’s happening in the U.S.,” Case added.

The outlook for Americans wasn’t always this grim. Since the middle of the 20th century, life expectancy has steadily climbed, with some small, albeit concerning, annual decreases in recent years. But in 2018, life expectancy improved by a small increment, from 78.6 to 78.7 years, which was the first time since 2014 that the number had gone up. A similar increase was recorded in 2019, the CDC reported.

Then came the coronavirus.

Life expectancy for the general population in 2020 was the lowest it has been since 2003, according to the latest report. “That’s pretty sobering,” said Noreen Goldman, a professor at the Princeton School of Public and International Affairs, who has published research on U.S. life expectancy during the pandemic.

Experts agree that one of the most significant findings of the report was the disparities among various populations. The virus was responsible for 90 percent of the decline in life expectancy among Latinos, 68 percent among the non-Hispanic White population and about 59 percent among the non-Hispanic Black population, according to the data.

Myriam Torres, a clinical associate professor of epidemiology and biostatistics at the University of South Carolina’s Arnold School of Public Health, called the data on Latinos “discouraging.”

“We Latinos have had a mortality advantage for some time,” said Torres, who referenced what academics refer to as the Hispanic or Latino paradox. “It was one thing going well for us.”

The fact that Latinos had a much higher life expectancy pre-pandemic but in 2020 experienced a decrease similar to non-Hispanic Blacks highlights “persistent structural inequalities” that can make certain minority populations more vulnerable to covid, Goldman said.

“Even a group that, in terms of health status, has been doing relatively well … that’s not enough to protect themselves given all of the kinds of social and economic inequalities that exist in society,” she said, referring to Latinos. “And when an infectious-disease killer comes around, those vulnerabilities are exposed.”

Many Latinos, Torres noted, have not been able to work remotely during the pandemic and are often in jobs where their risk of exposure to the coronavirus is increased but they don’t have adequate resources to protect themselves from infection. They rely on public transportation and tend to live in large, multigenerational households, both of which are factors that can increase the chance of infection.

It’s also possible Latinos were disproportionately harmed because many are undocumented, do not have access to federal pandemic relief aid or unemployment benefits and have to report to work during the pandemic, Torres said. Additionally, there may have been obstacles related to accessing coronavirus tests, treatments and vaccines, she said.

“These disparities have been there in general and particularly in African Americans,” Torres said. “It’s serious.”

The pandemic’s unequal effect on Black Americans is rooted in systemic racism, said Camara Phyllis Jones, a family physician, epidemiologist and past president of the American Public Health Association.

“The differences in life expectancy are structural racism revealed — just the baseline differences — because there’s no difference in our protoplasm,” she said. “There are only differences in our life experiences and life opportunities and how we are valued in this country.”

Some say the U.S. pandemic response may have also played a role in affecting life expectancy. Steven Woolf, director emeritus of the Center on Society and Health at Virginia Commonwealth University, recently published similar research that compared data in the United States to other countries and found a much steeper decline here.

From 2018 to 2020, the United States saw a drop in life expectancy that was 8.5 times the average decrease in 16 other high-income countries, such as France, Spain and the United Kingdom. And the drop among Latino and Black populations in the United States was 18 and 15 times higher than in peer countries, respectively.

He said it is at least in part because other countries — particularly those that saw increases in life expectancy during the pandemic — were quick to mount a national response, and “the population got the message and hunkered down and adopted social distancing and other procedures that allowed them to open up their economies sooner. Needless to say, that did not happen in this country, and there was a large loss of life as a consequence.”

Alison Gemmill, assistant professor at Johns Hopkins Bloomberg School of Public Health, said she is concerned about what the delta coronavirus variant, vaccine holdouts and the phenomenon known as long covid will mean for life expectancy going forward.

“Is this covid effect in life expectancy a one-time, one-year thing?” she said. “Not only is mortality going to be affected in the short term, but there may be many long-term effects that we don’t understand yet.”