UnitedHealth Group on Thursday said it expects to restore Change Healthcare's systems by mid-March, offering a potential resolution to the ransomware attack that has disrupted crucial operations across the U.S. health-care system. The company discovered that a cyber threat actor breached part of the Change Healthcare's information technology network on Feb. 21, according to a filing with the Securities and Exchange Commission. UnitedHealth isolated and disconnected the impacted systems "immediately upon det ...