Insurance executives and US health officials believe the worst effects of the Change Healthcare hack are easing and that the industry is in the last mile of the crisis.

A US official said on a call with health insurers on Monday that the Feb 21 cyberattack on the UnitedHealth Group Inc subsidiary is expected to cost the health-care system hundreds of millions of dollars, according to people familiar with the discussion. The hack halted billions of dollars in medical payments and left many providers under financial duress.