Assertive outreach enhances hepatitis B vaccination for people who inject drugs in Melbourne, Australia

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1 Assertive outreach enhances hepatitis B vaccination for people who inject drugs in Melbourne, Australia Peter Higgs, Nyree Chung, Shelley Cogger, Rebecca Winter, Margaret Hellard & Paul Dietze

2 Acknowledgements Participants for their time and involvement in the study Recruitment sites: SHARPS Frankston; Innerspace Collingwood; Health Works Footscray; Access Health St Kilda Salary support: Curtin University and NH&MRC Funding: NH&MRC (project grants #331312; #545891; and CRE ); Colonial Foundation Trust, Drug Policy Monitoring Project UNSW, Shepherd Foundation. MIX Study fieldwork team, in particular Cerissa Papanastasiou, Dan O Keefe and DeArne Quelch

3 Background I Liver cancer as a consequence of chronic hepatitis B virus (HBV) infection is a leading cause of illness and death But it is preventable In Australia, key population at risk of HBV exposure are people who inject drugs (PWID) Universal vaccination for primary prevention has been endorsed by the World Health Organisation and the Australian Government A large proportion of PWID in Australia require vaccination Previous studies have shown that modest motivational incentives are effective in increasing vaccination among PWID (Weaver et al., Lancet, 2014; Topp et al, Preventive Med, 2013)

4 Background II In 2008, 130,000 to 200,000 Australians were living with chronic HBV infection (Butler et al, 2009) Approximately 40% of new HBV infections occur among PWID However, PWID comprise a relatively low proportion of chronic cases given ~ 90% exposed adults achieve viral clearance (Dore et al, 2007) Co-infection with HBV and HCV confers greater risk of liver disease than mono-infection (Weltman et al, 1995; Sterling & Sulkowski, 2004) Given the high prevalence of HCV among PWID, it is important to vaccinate against HBV

5 Reduced by over two-thirds over 10 years 5/12 reported injecting and 3/12 had HCV diagnosed at same time

6 MIX Cohort N=688 Female (%) 33 Born overseas (%) 16 Mean age (years, range) 27.6 (16-40) Duration of injecting (mean years) 10 HCV Ab +ve (%) 78 HCV RNA +ve (%) 52 HBV naïve (%) 20 Lifetime receptive sharing NS (%) 45 Currently receiving OST (%) 35 Primary heroin injector (%) 82 History of incarceration (%) 60

7 Why is HBV vax important? 138 MIX participants were HBV-naïve at first blood collection These people tended to be older than others in the cohort Of these, 17 became HBV+ at subsequent serology 11 via HBV vaccination and six via exposure Source: AIVL Source: Hepatitis Victoria

8 Aims 1. To measure the efficacy of a standard schedule of HBV vaccination versus opportunistic accelerated schedule in terms of completion rates and immune response 3 doses over 6 months vs. 3 doses over a minimum of 3 weeks (plus a 12 month booster) To trial and evaluate access to HBV vaccination using an outreach delivery model among PWID To optimise HBV vaccination among the Melbourne Injecting Cohort Study (MIX) To evaluate the efficacy of the HBV vaccination outreach model via measures of vaccination schedule completion and immune response

9 Method Eligibility screening and participants receive first dose and baseline serology Randomization occurs and participants allocated to either of two arms Arm A Standard 3 dose schedule 0, 1 & 6 months Arm B Accelerated schedule 0, 7 & 21 days Then booster 12 months post Serology taken at each interview to see how sero-conversion progresses during follow up Post vaccine schedule serology 6 weeks after final vaccine dose

10 Preliminary results Participants reasons for not having been vaccinated: Unaware of HBV vaccination Confusion around HBV risk associated with drug injection and unprotected sex Prevention messages: HBV versus HCV Never previously offered HBV vaccination by a health worker Vaccination service provision not accessible Appointments/offsite screening/limited follow-up Despite consistent referral for vaccination by fieldworkers a large proportion remain naïve

11 Preliminary results Recruitment to the B-VAX project to date N=50 Accelerated schedule (n=26) 10 participants have completed schedule 12 participants have completed schedule (and await 12 month booster) 5 participants have received 2 doses of schedule Standard schedule (n=24) 11 participants have completed schedule 4 completed 2 doses of schedule 8 participants have completed 1 dose Currently, monitoring to see who has developed an adequate immune response (HBV sab+)

12 Preliminary results Why no previous HBV vaccination? Yeah, um, it was because of the service... it was always harder, a lot harder to get involved with the program, cause of like, having to go and do everything off our own bat, you know, call up, you know everything like that... (male, 33 years) A large proportion of those reporting previous HBV vaccination had no serological evidence of this why?? Full schedule incomplete? Failed to have a serological response (surface antibody positive) following vaccination

13 It s not just about HBV And if it wasn t for you guys and the mobile service, I don t think I would have got the hep B vax at all so there s a big difference between you guys being here I think you guys are kinder and do it better, you make the effort to make me feel comfortable Field based observations and feedback from participants suggest that modest contingency management incentives are part of an important tool of engagement. However, these alone are not enough. Participant-practitioner trust established through long-term assertive outreach is central to providing the enabling environment that is facilitates this important public health intervention.

14 Summary HBV is preventable, yet a large proportion of Australian PWID remain unvaccinated Initial results suggest that our participants are developing a response in both schedules PWID tend to underestimate the importance of vaccination Using an assertive outreach model, HBV vaccine delivery appears acceptable to PWID with whom we are already engaged