A cluster of acute rheumatic fever cases among Aboriginal Australians in a remote community with high baseline incidence

Objectives: We report a cluster of acute rheumatic fever (ARF) cases and the public health response in a high-burden Australian setting.

Methods: The public health unit was notified of an increase in ARF cases in a remote Australian Aboriginal community. A multi-disciplinary group coordinated the response. Household contacts were screened for ARF or group A Streptococcus (GAS) infection by questionnaire and swab collection, offered an echocardiogram if aged 5–20 years, and intramuscular benzathine benzylpenicillin if aged over one year or if less than one year with impetigo.

Results: Fifteen definite and seven probable ARF cases were diagnosed in the community in July–December 2014 (all-age incidence of definite ARF: 1,473/100,000). The public health response identified two additional cases of ARF. A total of 81 contacts were screened; GAS was detected in 3/76 (4%) throat swabs and 11/24 (46%) skin swabs. Molecular typing revealed high GAS strain diversity.

Conclusions: The incidence of ARF during this cluster was very high. Carriage and infection with GAS was observed, but no outbreak strain identified.

Implications for public health: A national public health guideline has since been developed that includes advice on the investigation of an ARF outbreak/cluster. Sustained efforts with strong community engagement are required to tackle high ARF rates.