Canterbury DHB says damp face masks could be why three medical staff caught Covid-19

The trio tested positive for Covid-19 after caring for patients from the Rosewood Rest Home cluster - where eight people have now died of the virus.

41 close contacts also employed by the DHB are in self-isolation after coming into contact with them.

Incident controller Sue Nightingale says they believe the staff caught the virus because they were too busy with sick patients to change their PPE.

She says workers reported their face masks had become moist from the physical exertion.

The DHB's put extra measures in place for staff dealing with Rosewood residents - including PPE Champions who make sure gear's being changed regularly.