Four people have been confirmed with measles while another 44 are in quarantine after an infected person ignored medical instructions to go into isolation when arriving on a flight from China.
Three of the cases stem from the passenger with measles who arrived on a flight from Guangzhou, China on January 30, visiting SkyCity Casino and Sugar Tree apartments between February 9 and 13.
The fourth case is unrelated to the China Southern Airlines flight.
All up, 48 people are in quarantine with more potential cases still being investigated.
"Some staff are working extra shifts and the phone is constantly ringing," doctor Richard Hoskins said today.
"I'm disappointed with this individual who disobeyed medical instructions for quarantine. They have let the public down and created a major upheaval for those involved."
The Auckland Regional Public Health Service (ARPHS) said they will not be issuing a public health alert for the fourth case as the exposure was contained to medical waiting rooms.
Patients in the waiting rooms are still being tracked down.
The person with the initial infection was at the casino between 9:45pm and 12am on February 9 and Sugar Tree apartments between February 9 and 13 with ARPHS advising that anyone who visited at those times could have been exposed to the disease.
Anyone who was infected would likely be experiencing symptoms, including a fever, runny nose, cough, sore eyes and a red botchy rash.
The illness is easily transmitted and is infectious even before a rash begins to form.
Anyone who visited Skycity Casino or Sugar Tree apartments during the specified dates and times are advised to go into quarantine if they are not immune to the disease or unsure of their measles immunity.