The nation's largest nurses union is calling on President Obama to impose strict national standards to protect healthcare workers from the deadly Ebola virus, pointing to a lack of safety protocols. The appeal Wednesday for swift executive action comes as the second Ebola diagnosis of a U.S. healthcare worker stokes fresh fears among employee advocates and raises questions about the scope of the federal government's response to the crisis. "This month has been a nightmare for the nurses across the nation," National Nurses United (NNU) Executive Director Rose Ann DeMoro said. "They're looking for answers."