A union sued two Las Vegas hospitals Thursday over a policy requiring hospital employees to receive flu shots -- or to wear surgical masks in patient areas if they are not vaccinated.

The Service Employees International Union Local 1107 sued Nashville-based Healthcare Corporation of America and two of its Las Vegas hospitals: Sunrise and its Sunrise Children's Hospital; and Southern Hills Hospital. HCA also owns MountainView Hospital in Las Vegas.

The lawsuit says the company has threatened to discipline employees who fail to abide by the policy, which the union says requires non-vaccinated employees to wear masks except when in cafeterias, break rooms, smoking areas and private offices.

HCA's decision to require vaccinations or the wearing of masks at all of its hospitals nationwide has helped fuel a national debate over whether health care workers should be required to receive vaccinations. HCA officials have said there's overwhelming evidence that vaccinations help prevent the spread of disease in hospitals.

The California Nurses Association/National Nurses Organizing Committee, which says it's the nation's largest nurses union with 86,000 members, issued a statement Sept. 30 saying vaccinations should be optional.

"The H1N1 virus presents a profound and unprecedented challenge to our nation’s fraying healthcare system. The H1N1 flu vaccine should be offered as one part of a comprehensive program to deal with this pandemic. That care plan must also contain immediate improvements to hospital infection control procedures, including the guarantee of an adequate supply of the appropriate N95 respirator masks as well as thoughtful isolation procedures, in addition to an immediate improvement to the public health safety net patients rely upon, and a moratorium of closures of hospitals and emergency rooms," nurse Deborah Burger, co-president of CNA/NNOC, said in a statement outlining the union policy on vaccinations.

"At the heart of this policy is the belief that every RN should be vaccinated against the H1N1 influenza virus, but nurses should maintain their right to decline for personal reasons," she said.

The two Las Vegas hospitals named in Thursday's lawsuit also are requiring the placement of stickers on employee name badges to indicate whether an employee has been vaccinated, says the lawsuit, filed by attorneys Jonathan Cohen in Pasadena, Calif.; and Michael Urban and Douglas Ritchie in Las Vegas.

The union says it's entitled to bargain with, consult and be heard concerning the hospitals' new policies.

Union attorneys in their lawsuit called the new rules a new condition of employment. They said they were initially announced on Aug. 19 when the hospitals said employees who could infect a patient or become infected would have to receive vaccinations for both seasonal flu and H1N1 flu, and anyone declining to be vaccinated would be required to wear the masks.

"The unilateral implementation of forced medical treatment or mandatory masking, and vaccination status identification badges, without bargaining with Local 1107 is inconsistent with the parties' collective bargaining agreements," the union charged in its lawsuit, filed in U.S. District Court in Las Vegas.

The union attorneys said they're seeking court intervention because, otherwise, the dispute will enter time-consuming arbitration.

"By the time a decision issues, affected employees will have suffered irreparable harm by having been forced to choose between forced medical treatment, revealing personal and private medical decisions with patients, co-workers, and the public, and termination," the lawsuit says.

The union says it represents registered nurses, certain service and technical employees, business office employees and various other non-professional employees at the hospitals.

Asked about the lawsuit, Sunrise Hospital issued this statement Friday:

"This is all part of our comprehensive infection control program and about protecting our patients. It is the flu season and the president has declared the pandemic a national emergency. We are on the front line of patient care and during emergent times we must take swift actions to ensure we can take care of our patients."