A study that could help prevent rheumatic fever among children is underway in the North Island.
Rheumatic fever, which starts with a particular type of sore throat, is the leading cause of childhood heart disease in New Zealand.
Up to 3000 schoolchildren from the Counties-Manukau, central Auckland and Bay of Plenty regions have been tested for sore throat.
Those with the condition will be tested again after treatment to see if they have developed rheumatic fever.
Lead researcher Diana Lennon from the University of Auckland says the results will help determine if school clinics are the most effective way of preventing the illness, or whether changes to treatment are needed.