Hepatitis C antibody testing among opioid agonist therapy recipients, Victoria, Australia, 2012 to 2020

Background The high burden of hepatitis C among people who inject drugs in Australia underscores the need to increase testing within this population. Understanding hepatitis C screening uptake in primary care settings is therefore critical to the development of effective and targeted strategies to improve hepatitis C testing for people who inject drugs. Primary care services that prescribe OAT are well-positioned to provide hepatitis C testing among a priority population at-risk of hepatitis C. Methods This study used linked data from 5,429 individuals attending ten clinical services participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance (ACCESS) who received their first recorded OAT prescription between 1st January 2012 and 31st December 2019. We estimated the proportion of OAT recipients who received a hepatitis C antibody test within 12 months of their first recorded OAT prescription, and the proportion of individuals tested who received a positive hepatitis C antibody test. Results Approximately one in five individuals (17%) received a hepatitis C antibody test in the 12 months following their first recorded OAT prescription. Over half of individuals tested (56%) received a positive hepatitis C antibody test result. Hepatitis C antibody testing was higher among individuals who attended 5–8 (aOR:2.98; 95%CI:2.41–3.69) and 9+ (aOR:6.17; 95%CI:5.13–7.43) clinical consultations, were women (aOR:1.20; 95%CI:1.08–1.34) and whose first recorded OAT prescription occurred in 2017 vs. 2012 (aOR:1.39; 95%CI:1.06–1.84). Hepatitis C antibody testing was lower among individuals prescribed methadone (aOR:0.81; 95%CI:0.73–0.91), and individuals aged 60+ years vs. 18-29 years (aOR:0.67; 95%CI:0.48–0.94). Conclusion Despite high positivity rates, hepatitis C antibody testing among individuals prescribed OAT remains low. There are opportunities for increased testing among populations exhibiting greater proportions of missed testing opportunities. Integrating routine hepatitis C screening in OAT settings will likely increase case-finding and contribute to Australia's hepatitis C elimination targets.