Health portal Manage My Health is still working to notify users affected by last week's major cyber breach

The College of GPs says the information mostly relates to inward letters from specialist appointments, and has affected Northland more than other regions.

Mike - one of the more than 100-thousand Kiwis afffected - says he has concerns about how cyber criminals could use his private information in the future.

He says he's going to struggle to trust the platform again.