A new national surveillance report reinforces acute rheumatic fever remains a serious public health concern in New Zealand, with rates returning to pre-pandemic levels and Māori and Pacific children continuing to be disproportionately affected.
The PHF Science report Rheumatic Fever in New Zealand 2015–2024 uses notifiable disease data to provide a comprehensive overview of rheumatic fever cases over the past decade.
Rheumatic fever is triggered by an autoimmune response to an infectious disease (Group A Streptococcus (GAS)) and can lead to rheumatic heart disease and lifelong harm.
From 2015 to 2024, there were 1,446 reported cases of rheumatic fever. The national rate peaked in 2018 at 3.0 cases per 100,000 population then declined significantly during the COVID-19 pandemic, reaching a low of 1.3 per 100,000 in 2021. However, this decline proved temporary. By 2023, rates had risen to 2.8 per 100,000, indicating a return to pre-pandemic levels.
Measures introduced to reduce COVID-19 transmission also reduced the transmission of other infectious diseases, including GAS. This is likely to be the driver behind lower incidences of rheumatic fever during that time and why incidence has increased since restrictions were loosened. This is also a trend seen internationally, including in Australia.
The report highlights significant and persistent inequities. Pacific and Māori children and young people continue to bear the greatest burden of disease. In 2024, Pacific children aged 5–14 years had the highest rate, followed by Pacific young people aged 15–24 years and Māori children aged 5–14 years.
Rheumatic fever cases were most common in the North Island, especially in the Northern Region. This region accounted for more than 60% of initial episode cases over the past decade, with the highest rates seen in Counties Manukau. Cases were much less common in the South Island.
Acute rheumatic fever is a preventable but serious illness that can cause lifelong heart damage. It is closely linked to factors such as crowded housing, barriers to healthcare, and socioeconomic disadvantage.
Report snapshot:
The national rate of initial rheumatic fever episodes:
- Peaked in 2018 at 3.0 cases per 100,000 population
- Declined significantly during the COVID-19 pandemic, reaching a low of 1.3 per 100,000 in 2021
- Returned to pre-pandemic levels in 2023 and 2024, with rates of 2.8 per 100,000 population in both years
Measures introduced to reduce COVID-19 transmission also reduced the transmission of GAS. This is likely to be the driver behind lower incidences of rheumatic fever during that time.
Māori and Pacific children remain disproportionately affected. In 2024, the highest rates were observed among:
- Pacific peoples aged 5–14 years: 76.7 per 100,000 (51 cases)
- Pacific peoples aged 15–24 years: 28.2 per 100,000 (18 cases)
- Māori aged 5–14 years: 25.5 per 100,000 (46 cases)
Notes to editors: The report also reviewed how cases were classified and found that overall trends remain reliable, even after updates to the case definition in 2025. The impact of the updated definitions will continue to be monitored in future reporting.