INDIANAPOLIS — Of all the Covid patients that Ronda Stevenson is treating over Christmas, there’s one she cannot stop thinking about. He has been hospitalized for 10 months, and in all that time his 7-year-old daughter has never once been allowed to visit, prohibited from the hospital by age restrictions that keep families separated. Situations like this are bringing even veteran health care workers to tears.

Ms. Stevenson, an intensive care unit nurse at Eskenazi Health in Indianapolis for the past seven years, cries as she talks about her patients and their families, making clear the grinding toll of the pandemic on already exhausted hospital workforces.

“We’re pretty short-staffed,” Ms. Stevenson said. She added: “It’s getting harder.”

Instead of taking holiday vacations this weekend, workers at strained hospitals across the nation are working 16-hour shifts. Some have been on the job every day for weeks. Festive meals have been replaced with protein bars and sports drinks.