Hospital‐Admitted Injection‐Related Infections Among Incarcerated People Who Inject Drugs in Australia: A Retrospective Cohort Study

OBJECTIVES: To characterise the clinical, microbiological and economic burden of hospital-admitted, injection-related infections among incarcerated people who inject drugs. STUDY TYPE: Retrospective observational cohort study. SETTING: Secure unit of the Princess Alexandra Hospital, Brisbane, Australia. PARTICIPANTS: Adults incarcerated in Queensland prisons who were admitted to hospital with an injection-related infection between 1 July 2019 and 30 June 2023. MAIN OUTCOME MEASURES: Types of injection-related infection, microbiological findings, requirement for surgical or radiological source control, hospital length of stay and inpatient healthcare costs. RESULTS: There were 321 hospital admissions for injection-related infection among 265 patients, accounting for 282 unique infections. Most patients were male (241; 90.9%), with a mean age of 33 years (standard deviation [SD], 7.4 years), and 76 (28.7%) identified as First Nations. The most frequent infections were soft tissue infections (77/282; 27.3%), acute hepatitis C (64/282; 22.7%) and cellulitis (43/282; 15.2%). Surgical or radiological source control was required in 95 infections (34.0%), and infectious diseases consultation occurred in 130 infections (46.1%). Among 39 true-positive blood cultures, Staphylococcus aureus was identified in 17 (43.6%), Burkholderia species in 10 (25.6%) and non-tuberculous Mycobacterium species in 3 (7.7%). Among the 218 non-acute hepatitis C infections, 50 (22.9%) were hepatitis C virus (HCV) RNA positive. Overall, HCV RNA was present in 114 of 282 infections (40.4%). The total inflation-adjusted inpatient cost was $8.39 million, with a median cost per infection of $11,602 (interquartile range, $7426-$34,544). CONCLUSION: Injection-related infections among incarcerated people who inject drugs were associated with substantial morbidity and healthcare costs in this large hospital cohort. A wide clinical spectrum was observed, including atypical pathogens, and clinically overt acute hepatitis C requiring hospital admission. These findings describe a significant burden of preventable disease in custodial settings and support the introduction of established primary prevention and harm-reduction interventions in prisons.