Two new measles cases have served as reminders for people to remain vigilant.

An infant in Canterbury is thought to have contracted the disease while in Auckland where there is more than 300 confirmed cases.

The child had not yet received their first MMR dose which is given at 15 months.

Anyone who isn't immunised and was in Christchurch Hospital Emergency Department on Friday night between 10pm and 3.45am Saturday or on Sunday between 11.40pm and 1.40am Monday should remain isolated until Monday the 5th of  August

It comes one day after it was announced a person who attended the Basketball New Zealand Under 15 Nationals competition over the weekend had measles.

Toi Te Ora Public Health is urging anyone who attended the event at Trustpower Arena in Mount Maunganui from July 17 to 20to be vigilant for the symptoms of measles.

Team members, family, staff and other spectators who attended the tournament may have been exposed.

It can take from seven to 14 days after exposure to start developing symptoms and therefore de Wet said anyone who was not immune and attended the tournament should be on the lookout for the symptoms of measles from July 24 until August 3.

The early symptoms of measles include fever, cough, runny nose and sore red eyes, and this is followed a few days later by a red, blotchy rash, usually starting on the face before moving down the body.

Measles is infectious to others from when the early symptoms start, even before the rash appears.

If you think you or someone in your family may have measles, it's important to stay at home and phone your doctor to alert them to your symptoms, and allow them to make arrangements to assess you safely and without infecting other people.

You can also call Healthline on 0800 611 116 for advice.

De Wet pleaded with people to not turn up to their doctor, after hours or emergency department without first phoning ahead, as they could potentially infect others in the waiting room.

For more information:
• Immunisation Advisory Centre free phone: 0800 IMMUNE (0800 466 863)
• Toi Te Ora Public Health, www.toiteora.govt.nz/measles
• Immunisation Advisory Centre, www.immune.org.nz
• Ministry of Health 2019 measles outbreak information
• Don't Assume You're Immune, www.getimmunised.org.nz