urveillance of severe diseases caused by group A Streptococcus (GAS) is needed in Australia. 1 Data reported in this issue of the MJA by Wright and colleagues 2 -the first from Western Australia -are timely, as the Australian government is considering recommendations to include invasive group A streptococcal diseases (iGAS) on the National Notifiable Diseases List. iGAS is a subset of the broad range of diseases caused by GAS, from superficial disorders (pharyngitis, impetigo) to invasive (sepsis, necrotising fasciitis, cellulitis, toxic shock syndrome) and autoimmune conditions (acute rheumatic fever, rheumatic heart disease, acute post-streptococcal glomerulonephritis). In Australia, GAS caused more than 750 000 health care episodes per year during 2005-2015, or 3.4 episodes/100 person-years for all GAS diseases, including 4.1 episodes/100 000 person-years caused by iGAS. 3 The estimated health care-related cost of GAS diseases was $185 million per year, making vaccination an economically viable prevention strategy. 3