Northland District Health Board staff members who have not had a flu jab are required to wear masks when dealing with at-risk patients this winter.
Margareth Broodkoorn, director of nursing and midwifery, said all staff were encouraged to have a flu jab as part of the national campaign promoting influenza vaccination, and three weeks into the vaccination programme 50 per cent of staff had been immunised.
The DHB was aiming for 70 per cent for the year. In 2014, 50 per cent of staff were vaccinated.
"If they choose not to, for medical reasons or otherwise, we require they wear a mask when treating at-risk patients, throughout our services, hospital and community based," Ms Broodkoorn said.
"This is a patient safety initiative, to protect those most at risk in our communities."