What are acute rheumatic fever and rheumatic heart disease?
Acute rheumatic fever
Acute rheumatic fever (ARF) is an autoimmune response to an infection of the upper respiratory tract by group A streptococcus bacteria. The infection can cause inflammation throughout the body including the heart, brain, skin and joints.
ARF is rare among most Australians, but still has a substantial impact on Aboriginal and Torres Strait Islander communities.
Early detection and treatment can prevent the bacterial infection progressing to ARF. The risk of ARF recurrence is high following an initial episode, and repeated episodes increase the chance of long-term heart valve damage.
Rheumatic heart disease
Rheumatic heart disease (RHD) is permanent damage of the heart muscle or heart valves as a result of ARF. RHD reduces the ability of the heart to pump blood effectively around the body, leading to symptoms such as shortness of breath after physical activity, fatigue and weakness. Severe forms can result in serious incapacity or death.
Symptoms of RHD can also occur with other heart conditions, making a diagnosis more difficult. Signs of damage detected by echocardiography and a history of ARF are both important clinical indicators for RHD diagnosis.
Risk factors and prevention of acute rheumatic fever and rheumatic heart disease
ARF and RHD are closely associated with social and environmental factors such as poverty, overcrowding, and reduced access to health care.
Secondary prevention of the progression from ARF to RHD relies on correct diagnosis, to enable commencement of regular antibiotic preventive medication. Guidelines recommend admission to hospital for clinical investigation and confirmation of the diagnosis of ARF (RHD Australia 2020).
Effective prevention, diagnosis and treatment remain a challenge in remote Indigenous communities. Under the Rheumatic Fever Strategy (RFS), the Australian Government provides funding to support RHD control programs in Queensland, Western Australia, South Australia and the Northern Territory.
Notifications of acute rheumatic fever
There were 2,244 notifications of ARF were recorded in Queensland, Western Australia, South Australia and the Northern Territory in 2015–2019 (4.7 per 100,000 population) (AIHW 2021). Of these:
- 95% (2,128 ARF notifications) were recorded among Indigenous Australians – a rate of 96 per 100,000 population over 2015–2019
- ARF was more common among Indigenous females than males, and rates were highest among Indigenous people aged 5–14 (1,029 notifications, 208 per 100,000)
- the number and rate of notifications has increased – from 342 (3.7 per 100,000) in 2015 to 477 (5.0 per 100,000) in 2019.
How many Australians have rheumatic heart disease?
As at 31 December 2019, there were 5,385 (56 per 100,000 population) people living with RHD recorded on registers in Queensland, Western Australia, South Australia and the Northern Territory (AIHW 2021).
Of these:
- 81% were Indigenous Australians (4,337 diagnoses, 955 per 100,000 population)
- 39% were aged under 25 (1,558 diagnoses)
- 66% were female (3,561 diagnoses)
- Northern Territory had the highest prevalence (2,308 diagnoses, 938 per 100,000).
Of those RHD diagnoses with severity status recorded, 41% had mild disease (2,206 diagnoses), while 28% had severe disease (1,532).
Older people were more likely to have severe RHD, with 42% aged 45 or over having severe disease (777 diagnoses), compared to 16% of those aged 15–24 (173 diagnoses).
New rheumatic heart disease diagnoses
In 2015–2019, there were 1,776 new RHD diagnoses in Queensland, South Australia, Western Australia and the Northern Territory (3.7 per 100,000 population).
Of these, 75% (1,325) were Indigenous Australians (60 per 100,000 population).
For the 4 jurisdictions combined, RHD diagnosis rates between 2015 and 2019 have remained relatively stable, at around 3–4 diagnoses per 100,000 population annually (Figure 1).
During this period, diagnosis rates varied by state and territory, but in general:
- South Australia had less than 1 diagnosis per 100,000 population
- Western Australia and Queensland had 2–5 diagnoses per 100,000
- Northern Territory had 40–60 diagnoses per 100,000.