St John ambulance staff have been quarantined as Auckland's measles outbreak continues to spread.
Since June, there have been 182 confirmed cases of measles in the city, with 11 in past week.
St John medical director Dr Tony Smith said one Auckland staff member has been confirmed to have become infected with measles.
"The staff member has been off work but not sick enough to be admitted to hospital," he said.
"The diagnosis was confirmed at the end of last week and we do not know how they became infected."