Poster Presentation Lancefield International Symposium for Streptococci and Streptococcal Diseases 2025

Invasive group A streptococcal infections in Australian adults – a descriptive cohort and cost burden study (#31)

Jessie J Goldsmith 1 , Sara L Whittaker 2 , Eddie Chan 3 , Jake A Lacey 4 , Sandra A Johnson 4 , Najma Kori 5 , Te-Yu Hung 6 , Janet Strachan 7 , Nigel W Crawford 8 , Norelle Sherry 4 9 , Natasha K Brusco 2 , Katherine B Gibney 1 10
  1. Department of Infectious Diseases, University of Melbourne, Melbourne, Victoria, Australia
  2. Rehabilitation, Ageing and Independent Living (RAIL) Research Centre, Monash University, Frankston, Victoria, Australia
  3. Department of Microbiology, The Royal Melbourne Hospital, Melbourne, Victoria, Australia
  4. Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
  5. Department of Medicine, Universiti Kebangsaan, Kuala Lumpur, Malaysia
  6. Department of Paediatrics, Royal Darwin Hospital, Darwin, Northern Territory, Australia
  7. Department of Health, Victorian Government, Melbourne , Victoria, Australia
  8. Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia
  9. Department of Infectious Diseases & Immunology, Austin Health, Heidelberg, Victoria, Australia
  10. Victorian Infectious Diseases Service, at the Peter Doherty Institute for Infection and Immunity, The Royal Melbourne Hospital, Melbourne, Victoria, Australia

 Investment in research to improve prevention and management of invasive group A streptococcal (iGAS) is needed because the incidence of iGAS is increasing and there is evidence that clinical management may vary substantially. We describe the epidemiology, clinical course, genomics, and cost burden of hospital care of invasive group A streptococcal (iGAS) amongst adults (≥18 years) treated at the Royal Melbourne Hospital during 2018-2023 and extrapolated the findings to estimate the annual healthcare cost burden of treating adult iGAS cases in Australia.  

There were 79 iGAS cases in our retrospective cohort study, seven of which died of the disease during their initial hospital admission (case fatality rate: 9%, 95% CI: 4%–18%). Eleven cases (14%) received intravenous immunoglobulin, 29 (35%) were admitted to intensive care and 45 (57%) required surgical intervention.  Of the 72 survivors, 19 (26%) did not receive either benzylpenicillin or amoxicillin/amoxicillin-clavulanate, two-thirds (66%) received clindamycin and more than a third (n=27, 38%) were discharged with an impairment.   

The single hospital cost burden analysis found the average iGAS disease-related healthcare cost was $63,662 (SD $84,743) per person, with a combined healthcare utilisation cost for this cohort of $5,029,305. Most costs (80%) were incurred during the index admission. The national extrapolation found the iGAS healthcare cost burden among adults in Australia was $117.5 million in 2023.  

iGAS among adults in Australia generates a significant health and financial burden. Our findings highlight the importance of further research to prevent iGAS and identify the optimal treatment for this severe infection.