Public health officers are concerned that Auckland could be on the brink of a measles outbreak.
They say two passengers had measles when they were on Flight NZ 136 from Brisbane to Auckland last Sunday.
An Auckland medical officer of health, Richard Hoskins, says the passengers who were sitting close by will be traced.
He says there have been 58 cases of measles in Auckland so far this year and officials are worried the disease will spread.
Measles symptoms can include a high fever, cough, runny nose, red eyes and a rash that starts on the face and neck before spreading elsewhere.