U.S. hospitals faced a surge in many other kinds of infections as COVID-19 taxed health-care capacity across the country last year, according to a new report from federal researchers.

Four types of health-care infections commonly tracked as core measures of hospital quality increased significantly in 2020, compared with what would have been expected based on prior years’ rates, researchers from the Centers for Disease Control and Prevention reported in a journal article Thursday.

The increases show how the pandemic’s strain on hospitals rippled into other aspects of caring for patients. During COVID surges, facilities often stretched the limits of their staff, equipment and bed space — conditions that returned in some states during this summer’s wave.

At the time, experts cautioned that the crisis conditions — reusing some personal protective equipment, improvising new intensive-care beds, assigning more patients to each nurse — would have consequences on quality of care.

“Hospitals saw a large influx of really critically ill patients, many of whom had what we already know of to be risk factors for these very infections,” said David Calfee, an infectious disease physician at Weill Cornell Medicine in New York. “We had severe reduction in resources in both supplies as well as staff.”

The pandemic conditions likely affected other measures of health-care quality as well, said Calfee, who studies hospital infections.

The health-care industry has been trying to improve hospital safety for decades and reduce the rate at which patients contract infections in medical settings. Infection rates, sometimes linked to hospital reimbursements by the government, had been declining for years before the pandemic.

Three types of infections linked to equipment attached to patients, like catheters and ventilators, rose sharply last year, according to the CDC report published in the journal Infection Control & Hospital Epidemiology. The fourth was a measure of the antibiotic-resistant bacteria known as MRSA.

Some of the increases were large: Infections associated with central lines used to deliver medication to patients jumped by about 47% in the second half of 2020 compared with the year before.

Two other types of infections, associated with surgical sites and an illness known as C. diff, didn’t increase.

The CDC researchers evaluated standardized infection rates that took into account changes in the number of patients in different periods.

The data reinforce the need to adhere to infection-control practices even in times of crisis.

“Basic infection control practices must be hardwired into practice so that they are less vulnerable when the health care system is stressed,” researchers from the National Institutes of Health wrote in an editorial accompanying the study.

“It is upon us to learn from it and to get better because of it,” said Calfee, who edits the journal in which the findings were published but wasn’t involved in the research.