Northland Health says parents would be wise to make sure their children are protected from the measles virus following outbreaks in other centres.
Cases have been reported in Auckland, Wellington and Christchurch after infected passengers arrived in the country from overseas flights in January.
Northland medical officer of health Claire Mills has confirmed that a person with measles visited Northland in the infectious stage - before a rash appeared.
Dr Mills says the illness can look like a cold in the early stages, but can make children very sick for up to two weeks and the best protection is vaccination.