Gun deaths increased during the first year of the pandemic, the CDC reports.

Gun deaths reached the highest level ever recorded in the United States in 2020, the first year of the pandemic, the Centers for Disease Control reported. Gun-related killings, in particular, increased by 35%, a spike that took an unprecedented toll on black men, the agency’s researchers said.

“This is an historic increase, with the rate reaching its highest level in over 25 years,” said Dr. Debra E. Houry, CDC’s acting deputy chief executive and director of the National Center for Injury Prevention and Control, said at a news conference Tuesday.

“We need to be vigilant in addressing the conditions that contribute to homicides and suicides and the disparities observed,” he added.

More than 45,000 Americans died in gun-related accidents as the pandemic spread to the United States, the highest number on record, federal data show. But more than half of the gun deaths were suicides, and that number hasn’t increased substantially from 2019 to 2020.

The overall increase in gun deaths was 15% in 2020, less than the percentage increase in gun deaths, the CDC said.

The rise in gun killings was the largest one-year increase seen in modern history, according to Ari Davis, a policy consultant at the Johns Hopkins Center for Gun Violence Solutions, who recently released his analysis of the CDC data. .

He said preliminary data suggests that gun deaths remained consistently high in 2021.

Federal officials and outside experts aren’t sure what caused the increase in gun deaths. The increase matched the acceleration in firearms sales as the pandemic spread and blockades became the norm, the CDC noted.

But federal researchers also cited an increase in social, economic and psychological stressors; disruptions in routine health care; tension between police and community members following the murder of George Floyd; an increase in domestic violence; unfair access to health care; and the long-standing systemic racism that contributes to poor housing conditions, limited educational opportunities and high rates of poverty.

Murders involving firearms were generally the highest and showed the largest increases in poor communities.

“One possible explanation is the stressors associated with the Covid pandemic that may have played a role, including changes and disruptions to services and education, social isolation, housing instability and difficulties in covering daily expenses,” said Thomas R. Simon, associate director of science at the agency’s division for violence prevention.

Black Americans were disproportionately affected by gun violence in 2020. Gun homicide rates increased by 39.5 percent among blacks from 2019 to 2020, to 11,904. The victims were mostly young men.

The Johns Hopkins analysis found that black Americans accounted for 38 percent of all gun murder victims in 2020, although they represented only 2 percent of the U.S. population.

Blacks between the ages of 15 and 34 were more than 20 times more likely to be killed with a gun than whites of the same age. The number of black women killed by gunfire also increased by nearly 50 percent in 2020 compared to 2019, Davis said.

Rising rates of gun-related homicides were seen across all racial and ethnic groups, the CDC said, with the exception of Americans of Asian and Pacific Island descent, which saw a small decrease..

Gun-related suicides have long been more common among older white men. But in 2020, rates increased dramatically among Native American and Alaskan native groups.

“Suicides impact a different, typically middle-aged population than older white men in rural communities,” said Mr. Davis. “We will need to develop different types of solutions to address different types of gun violence.”