A Kaiser mental health worker with the National Union of Healthcare Workers looks through a pile of signs Monday during day one of a week-long demonstration outside of a Kaiser Permanente hospital in San Francisco. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images

Members of the California Nurses Association rallied in Sacramento, Calif., in May, in anticipation of contract negotiations with Kaiser Permanente that began this fall. April Dembosky / KQED hide caption

itoggle caption April Dembosky / KQED

Nurse Fatima Guillen (left) gives 4-year-old Kimberly Magdeleno a whooping cough booster shot at a health clinic in Tacoma, Wash., in May. Ted S. Warren/AP hide caption

itoggle caption Ted S. Warren/AP