Antimicrobial surveillance in South Australian prisons: a pilot study

This study aimed to determine the feasibility of capturing antimicrobial usage data from prisons for inclusion in the Antimicrobial Use and Resistance in Australia (AURA) surveillance system and to analyse 2021 and 2022 South Australian (SA) usage data for notable trends.

Monthly antimicrobial supply data for eight SA prisons were collected. Antimicrobial volume was converted into the World Health Organization metric, defined daily doses (DDD). Usage rates were calculated relative to prison occupied bed days (OBD).

Annual usage of systemic antimicrobials across eight SA prisons totalled 26,448 DDD and 23,526 DDD in 2021 and 2022 respectively. Antibacterials accounted for 80.6% of all antimicrobials dispensed during the study period. The average antibacterial usage rate in female prisons was higher on average than in male prisons. The state-wide systemic antibacterial usage rate in SA prisons declined by 11.3% from 23.8 DDDs/1000 OBD in 2021 to 21.1 DDDs/1000 OBD. Doxycycline, amoxicillin, flucloxacillin, amoxicillin-clavulanic acid, and cefalexin accounted for 72% of the total systemic antibacterial usage rate. Variation in the oral and topical antifungal agents used and the rate of use was observed between prisons.

This SA pilot study demonstrates the feasibility of including prisons in routine national antimicrobial surveillance using similar methodology to hospital surveillance. The contributing facilities comprised 6.1% of all Australian prison beds, and extrapolation of the results suggests that the identified gap in surveillance may equate to over 400,000 DDD per annum in prisons nationwide, equating to approximately 5% of hospital inpatient antimicrobial usage.