Three hospital workers in Auckland who cared for people infected with Covid-19 from St Margaret's Hospital and Rest Home have tested positive for the disease.
The staff worked on the ward where the patients had been transferred due to staffing shortages at the rest home, Waitematā District Health Board said.
The DHB said it was not clear whether contact with those patients was the source of the staff contracting Covid-19 or whether any of the cases are linked.
Full protective equipment was made available and worn by staff at all times in the ward, it said.
An urgent review is in progress to understand how and where the infection may have occurred.