The Ministry of Health says it has 10 confirmed cases of measles affecting people who attended a hip-hop competition in Sydney and it is possible that figure could rise.
The people are from Auckland, Taupo and Turangi and either went to the competition or have been in contact with someone who attended.
Harriette Carr, acting deputy director of public health, says it is possible the number of people affected could increase.
Dr Carr says these people were not immunised for measles and health officials are in touch with people they've been in contact with.
She says it's important that people who think they might have measles contact their GP, rather than turn up at a hospital and possibly infecting others.
