People are being urged to be on guard after the first case of measles in the Auckland region since June 2012 was confirmed.
One person was confirmed as contracting the infectious disease while in Sydney earlier this month where they were taking part in the 2013 World Supremacy Battlegrounds hip-hop competition, the Auckland Regional Public Health Service said.
The services was aware that teams from elsewhere in New Zealand, including Hamilton and Huntly, also attended the event.
The service was following up with people who had contact with the infected person, had alerted Auckland health professionals and emergency departments and updated the Ministry of Health.
Medical Officer of Health Dr Catherine Jackson warned that measles was extremely infectious and could cause serious complications.