The My Health Record Opt-out helpline is back up and running following a system crash that occurred when the line was inundated with Australians trying to opt-out before the deadline.

A spokeswoman for Health Minister Greg Hunt has defended the crash of the telephone opt-out service, stating that it was due to a technical issue as opposed to an influx of calls.

17 million Australians will be automatically enrolled in the My Health Record despite ongoing privacy concerns if they do not opt out by next Thursday.