(Bloomberg) -- More than 15,000 nurses across 16 hospital systems in Minnesota began a three-day strike on Monday after months of contract negotiations failed to produce a new deal.

The Minnesota Nurses Association, a union whose members also work in Wisconsin, North Dakota and Iowa, said that while its nurses have sought solutions to staffing shortages and retention issues, hospital executives have focused discussions solely on raising wages. But remedying the fallout from more than two years of pandemic burnout will take more than that, and not doing so puts patients at risk, the union said.

“Nurses do not take this decision lightly, but we are determined to take a stand at the bargaining table, and on the sidewalk if necessary, to put patients before profits in our hospitals,” Mary C. Turner, a registered nurse and president of the union, said in a statement.

The union said the walkout is believed to be the largest private-sector nurses strike in US history. It comes amid ongoing labor strife across the nation. Mental-health workers at Kaiser Permanente hospitals in California and Hawaii are striking for a new contract and expanded resources. And freight-rail operators and labor unions are working to hammer out a new contract before Friday’s deadline or risk major supply chain disruptions that could cost the US economy billions each day. 

In a survey of 2,500 nurses released in July by the nurse-staffing start-up Trusted Health, three-quarters of respondents said they had experienced burnout since the onset of the Covid-19 pandemic. Half said they had felt extreme trauma, stress or post-traumatic stress, and 64% said they were considering leaving health care entirely.

Nurses across the country are walking out from their jobs to demand change. One group of about 5,000 nurses in Palo Alto, California, staged a strike in April; they later won a new contract with their employers, Stanford Health Care and Lucile Packard Children’s Hospital. The US Bureau of Labor Statistics estimates there will be an average of 194,500 job openings for registered nurses through 2030. 

US Representative Ilhan Omar, a Democrat from Minnesota, said on Twitter that she planned to stand with the striking nurses, and Democratic US Senator Bernie Sanders of Vermont also tweeted in support of the strike.  

“I stand in solidarity with the 15,000 @mnnurses on strike this week fighting for safer care, fair scheduling, and higher wages,” Sanders wrote. “Nurses are the backbone of our health care system. They understand what’s best for their patients.”  

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