The CDHB community and public health team was identifying family members and close contacts, determining their immunisation status and offering vaccination if appropriate.
Canterbury medical officer of health Dr Alistair Humphrey said it was more important than ever for people to check they were vaccinated.
People were infectious from five days before the onset of the rash until five days after the rash appeared, so it was possible to transmit the infection before you felt unwell.
"Because measles is so infectious, it's important people with symptoms do not visit their general practice team, after-hours clinics or the hospital unless it's a medical emergency.
"To limit further exposure to other people, they should instead phone their family doctor/general practice team for advice."
Children should routinely receive the MMR vaccine at 15 months and at 4. In an outbreak, this timing may change.
Anyone who has not had two documented doses of MMR vaccine is eligible for free vaccines.
Once a person contracts measles, it can be 10 to 14 days before they begin seeing symptoms. Such symptoms include a high fever, runny nose, cough and sore red eyes. A few days later a rash starts on the face and neck, and then spreads to the rest of the body.
People born before January 1, 1969, are considered to be immune because virtually everyone got measles prior to the vaccine being introduced that year, and so this older age group does not need the measles immunisation.
It is particularly important to check your immunity if you are planning an overseas trip.
The Ministry of Health recently highlighted that since 2012, all outbreaks of measles in New Zealand were started by travellers bringing the disease from overseas. There are currently significant measles outbreaks in many countries.
If you are concerned about measles call Healthline on 0800 611 116 or your GP.
Please do not just turn up to your GP, after-hours or emergency department because you could potentially infect others.
