Community-associated methicillin-resistant in the Kimberley region of Western Australia, epidemiology and burden on hospitals.

This study presents surveillance data from 1 July 2003 to 30 June 2023 for community-associated methicillin-resistant (CA-MRSA) notified in the Kimberley region of Western Australia (WA) and describes the region's changing CA-MRSA epidemiology over this period. A subset of CA-MRSA notifications from 1 July 2003 to 30 June 2015 were linked to inpatient and emergency department records. Episodes of care (EOC) during which a positive CA-MRSA specimen was collected within the first 48 hours of admission and emergency presentations (EP) during which a positive CA-MRSA specimen was collected on the same day as presentation were selected and analysed further. Notification rates of CA-MRSA in the Kimberley region of WA increased from 250 cases per 100,000 populations in 2003/2004 to 3,625 cases per 100,000 in 2022/2023, peaking at 6,255 cases per 100,000 in 2016/2017. Since 2010, there has been an increase in notifications of Panton-Valentine leucocidin positive (PVL) CA-MRSA, predominantly due to the 'Queensland Clone'. PVL CA-MRSA infections disproportionately affect younger, Aboriginal people and are associated with an increasing burden on hospital services, particularly emergency departments. It is unclear from this study if PVL MRSA are associated with more severe skin and soft-tissue infections, and further investigation is needed.