IPU has also suspended classes for two weeks, and the dining hall, library and rec centre remain closed until further notice.
MDHB medical officer of health Dr Greg Simmons said they were working closely with IPU who had been following all of their recommendations.
"Public Health will continue to work with the institute to provide assistance and trace the contacts of the confirmed cases. Measles is a very infectious disease so anyone who is not immune to measles is at risk if they come in to contact with the disease."
Measles can spread by air, from person-to-person through breathing, sneezing, coughing or any contact with secretions.
"The disease is contagious from just before symptoms begin until about five days after onset of the rash," Dr Simmons said.
"The illness usually starts between 10 and 14 days after contact with the measles virus."
Symptoms can include a fever, runny nose, cough and sore, red eyes. A rash occurs after three to five days, appearing on the head and spreading down the body.
"These cases are a reminder that measles can occur at any time. Vaccination is the best way for people to protect themselves against measles and is free to those who need it. You can protect both yourself and the community by getting vaccinated."
Anyone who thinks they may have measles should stay away from work, school or public places. If you think you might have measles, contact your GP (by phone first) or Healthline on 0800 611 116 for more advice. It is very important you tell your GP you think you might have measles before going into the surgery.