Auckland's mumps outbreak has become an epidemic and a vaccination campaign is needed to stop it spreading across New Zealand, health experts say.
More than 1000 people have caught mumps in Auckland this year, with the number of cases almost doubling since the start of October.
All Blacks winger Rieko Ioane was among those to contact the mumps.
The outbreak was now an epidemic because it could not be contained, the public health officials say in a joint letter to the Ministry of Health.
The letter was signed by the chief executives of Auckland, Counties Manukau and Waitemata district health boards, and two senior Auckland Regional Public Health service officials, RNZ reports.
With current measures to contain the disease having little impact, a more high profile vaccination campaign was needed, the officials said.
About 80 per cent of current cases were in people not immunised, including among a so called "lost generation" of 10-29-year-olds with particularly low rates of the measles, mumps and rubella vaccination. The ministry is expected to reply to the DHBs shortly.
Mumps can cause painful swelling of the glands around the face and jaw, fever and headaches. The measles, mumps and rubella vaccination is free from doctors.