Aristotle HCV-HIV

ARISTOTLE HCV-HIV was a community-based programme aiming to promote HCV and HIV screening among people who inject drugs (PWID) in Athens and linking those infected to care.

Between 2018 and 2020, the programme ran a peer-driven chain referral method with monetary incentives, designed to reach the population of PWID most at risk (current injectors, not linked to other services). All tests were offered on site and chronic hepatitis C patients were linked to a network of hepatologists that was specifically set up for the programme.

The programme was implemented by the Hellenic Scientific Society for the Study of AIDS, STDs and Emerging Diseases (EEEEAIDS) and the Hellenic Liver Patient Organisation “Prometheus”.2


A high HCV prevalence is documented among the PWID population of Athens, which is the largest in Greece. Inspired by the success of a community-based intervention which improved HIV testing and linkage to care among PWID in 2012/2013 and which was highlighted as a good practice example by WHO, ARISTOTLE HCV-HIV was launched. The project was further triggered by the availability of direct acting antivirals (DAAs) for HCV and the frequent risky injection behaviours and blood-borne infections amongst PWID in Athens.


The programme was designed to address and minimise barriers in reaching out to PWID, testing them and linking them to care:

  • Peer-driven chain referral, through successive respondent-driven sampling (RDS) recruitment rounds, was used to provide community-based testing at a fixed location in the centre of Athens, in an area easily accessible to PWID.
  • Blood samples were collected during the first visit to the programme, as well as free laboratory testing and transient elastography for those testing anti-HCV positive (test results are needed to request approval for free administration of DAA in Greece).
  • A network of hepatologist collaborators was set up to include patients who fulfil HCV treatment criteria in the national registry of hepatitis C patients, to request permission for them to initiate treatment with DAAs, and subsequently, to treat the patients.
  • A peer-navigator accompanied patients to the first appointment with the doctor at the hepatology clinic.


Between 2018 and 2020, 1,635 PWID participated in the programme: 27% were homeless, 75% were active PWID (past 30 days) and 77% were not currently on opioid substitution treatment (OST). Based on the official PWID population estimate for Athens, the population coverage achieved by ARISTOTLE HCV-HIV was approximately 82%. HCV prevalence was about 76%. Among PWID with chronic HCV monoinfection who fulfilled the treatment criteria (there were restrictions up to September 2019), it was possible to identify a social security number for 88% of them, 46% were linked to HCV care and 40% had initiated treatment by March 2021.


This approach proved successful in achieving high population coverage and in minimising the barriers to linkage to care.

ARISTOTLE HCV-HIV was successful for a several reasons:

  • Peer-driven chain referral allowed the initiative to reach the most vulnerable PWID population (i.e., current drug users or homeless people not linked to other healthcare services).
  • Successive recruitment rounds not only facilitated achieving a high population coverage, but also improved linkage and retention to care.
  • Testing and linkage to care were provided onsite with the help of a network of clinicians and dedicated staff/peer navigators.
  • The close collaboration of academia, clinicians and patients’ organisations.


Private funding.


Vana Sypsa, National and Kapodistrain University of Athens Greece