OMAHA, Neb. — A year after U.S. health care workers on the front lines against COVID-19 were saluted as heroes with nightly clapping from windows and balconies, some are being issued panic buttons in case of assault and ditching their scrubs before going out in public for fear of harassment.

Across the country, doctors and nurses are dealing with hostility, threats and violence from patients angry over safety rules.

“A year ago, we’re health care heroes and everybody’s clapping for us,” said Dr. Stu Coffman, a Dallas-based emergency room physician. “And now we’re being in some areas harassed and disbelieved and ridiculed for what we’re trying to do, which is just depressing and frustrating.”

Cox Medical Center Branson in Missouri started giving panic buttons to up to 400 nurses and other employees after assaults per year tripled between 2019 and 2020 to 123, a spokeswoman said. One nurse had to get her shoulder X-rayed after an attack.

Hospital spokeswoman Brandei Clifton said the pandemic has driven at least some of the increase.

“So many nurses say, ‘It’s just part of the job,’” Clifton said. “It’s not part of the job.”

Some hospitals have limited the number of public entrances. In Idaho, nurses said they are scared to go to the grocery store unless they have changed out of their scrubs so they aren’t accosted by angry residents.

Doctors and nurses at a Coeur d’Alene, Idaho, hospital have been accused of killing patients by grieving family members who don’t believe COVID-19 is real, said hospital spokeswoman Caiti Bobbitt.

Over Labor Day weekend in Colorado, a passerby threw an unidentified liquid at a nurse working at a mobile vaccine clinic in suburban Denver. Another person in a pickup truck ran over and destroyed signs put up around the clinic’s tent.

About 3 in 10 nurses who took part in a survey this month by an umbrella organization of nurses unions across the U.S. reported an increase in violence where they work stemming from factors including staff shortages and more visitor restrictions. That was up from 2 in 10 in March, according to the National Nurses United survey of 5,000 nurses.