As News Breaks that Second Health Worker in Dallas Tests Positive for Ebola, 11,500 RNs Join National Conference Call for Nurses on Preparedness. With concern escalating across the U.S. about the threat of a wider Ebola outbreak, National Nurses United today called on President Barack Obama to “invoke his executive authority†to order all U.S. hospitals to meet the highest “uniform, national standards and protocols†in order to “safely protect patients, all healthcare workers and the public.â€