A second case of measles has been confirmed in Christchurch.

An 11-year-old child has contracted the virus after coming into contact with a 30-year-old man last month in a general practice waiting room.

The man had previously contracted the virus overseas.

Canterbury Medical Officer of Health, Dr Alistair Humphrey, says these are the first cases of measles in Canterbury since May 2017.

Community and Public Health staff are working to contain any potential spread and warning those who came into contact with the child.

The child attended a service at Our Lady of Victories Church on February 3, went to Nando's Restaurant in Sydenham between 5pm and 7pm on Waitangi Day and was at the Margaret Mahy Playground for a short period between 5pm and 10pm.

There is no risk to anyone who has been to the church for another service or attended the restaurant or playground outside of those times, Dr Humphrey said.

If you fall into that category and feel unwell, advice is to stay at home and call your GP for medical advice - staying at home is important in case you are contagious.

The early symptoms of measles include fever, cough, runny nose, sore red eyes and white spots inside the mouth and after three to five days a rash may appear.

Dr Humphrey says the re-emergence of the virus is a timely reminder to everyone to ensure they are fully immunised.