Incidence of primary hepatitis C infection among people who inject drugs during 2012-2020 in Athens, Greece.

One of the World Health Organization's targets for the 2030 viral hepatitis elimination strategy is to reduce new hepatitis C (HCV) infections. In Athens, Greece, people who inject drugs (PWID) have a high HCV prevalence, with increasing trends since the 2000s. This analysis aims to assess primary HCV incidence among PWID during 2012-2020. Two community-based interventions were implemented in 2012-2013 and 2018-2020 with repeated sero-behavioural surveys in each period. Participants enrolled in multiple surveys were identified through linkage. To assess trends in HCV transmission, three indicators were estimated: (i) anti-HCV prevalence among 'new' injectors (those injecting ≤2 years), (ii) indirect HCV incidence among 'new' injectors, assuming infection occurred at the midpoint between initiating injection and the first positive test, and (iii) HCV incidence from repeat participants. There were 431 and 125 'new' injectors, respectively, in 2012-2013 and 2018-2020. Αnti-HCV prevalence [95% CI] declined from 53.6% [48.8%, 58.3%] in 2012-2013 to 40.0% [31.3, 49.1%] in 2018-2020 (25.4% reduction, p = .007). The indirect estimate [95% CI] of HCV incidence among 'new' injectors decreased from 56.1 [49.3, 63.8] to 39.0/100 person-years (PYs) [29.6, 51.5] (30.5% reduction, p = .020). HCV incidence [95% CI] based on seroconversions in repeat participants (16/63 in 2012-2013 and 9/55 in 2018-2020) declined from 64.6 [39.6105.4] to 13.8/100 PYs [7.2, 26.5], respectively (78.6% reduction, p < .001). Primary HCV incidence remains high among PWID in Athens. Consistent implementation of combined interventions, including high-coverage harm reduction programs and initiatives tailored to increase access to HCV treatment, is essential to sustain the declining trends documented during 2012-2020.

Molecular epidemiology of HIV among people who inject drugs after the HIV-outbreak in Athens, Greece: Evidence for a 'slow burn' outbreak.

BACKGROUND: New diagnoses of HIV-1 infection among people who inject drugs (PWID) in Athens, Greece, saw a significant increase in 2011 and a subsequent decline after 2013. Despite this, ongoing HIV-1 transmission persisted from 2014 to 2020 within this population. Our objective was to estimate the time of infection for PWID in Athens following the HIV-1 outbreak, explore the patterns of HIV-1 dispersal over time, and determine the duration from infection to diagnosis. METHODS: Time from HIV-1 infection to diagnosis was estimated for 844 individuals infected within 4 PWID-specific clusters and for 8 PWID infected with sub-subtype A6 diagnosed during 2010-2019. Phylogeny reconstruction was performed using the maximum-likelihood method. HIV-1 infection dates were based on molecular clock calculations. RESULTS: In total 86 of 92 (93.5%) sequences from PWID diagnosed during 2016-2019 were either related to the previously identified PWID-specific clusters (n = 81) or belonged to a new A6 cluster (n = 5). The median time between infection and diagnosis was 0.42 years during the outbreak period and 0.70 years during 2016-2019 (p < 0.001). The proportion of clustered sequences from PWID was very low at 5.3% during the pre-outbreak period (1998-2009), saw an increase to 41.7% one year before the outbreak in 2010, and consistently remained high during the whole period after 2011, spanning the post-outbreak period (2016-2019) with a range from 92.9% to 100%. CONCLUSIONS: The substantial proportion of clustered infections (93.5%) during 2016-2019 implies a persistent 'slow burn' HIV outbreak among PWID in Athens, suggesting that the outbreak was not successfully eliminated. The consistently high proportion of clustered sequences since the onset of the outbreak suggests the persistence of ongoing HIV-1 transmission attributed to injection practices. Our findings underscore the importance of targeted interventions among PWID, considering the ongoing transmission rate and prolonged time from infection to diagnosis.

High levels of all-cause mortality among people who inject drugs from 2018 to 2022.

BACKGROUND: Mortality among people who inject drugs (PWID) is high, with overdose and HIV infection being the main causes of death. In Greece, there have been no data on mortality, and two HIV outbreaks have been recorded in this population in the past decade. In this study, we aim to estimate the all-cause crude mortality rate and the standardised mortality ratio in this population during 2018-2022. METHODS: PWID recruited from two community-based programs in Athens and Thessaloniki during 2018-2021 were interviewed and tested for HIV/HCV. Data on vital status (deceased/alive) and date of death were obtained from death registries through December 31, 2022. All-cause crude mortality rates (CMR) and standardised mortality ratios (SMR) were estimated. Determinants of mortality were assessed using Cox proportional-hazards model. RESULTS: Of 2,530 participants, 301 died over 8,543 person-years (PYs) of follow-up. The CMR (95 % CI) was 3.52 (3.15-3.94) deaths per 100 PYs; 3.10 per 100 PYs (2.68-3.58) in Athens and 4.48 per 100 PYs (3.74-5.37) in Thessaloniki. An increasing trend in CMR was identified over 2018-2022 in Athens (from 2.90 to 4.11 per 100 PYs, 41.5 % increase, p = 0.018). The pooled SMR (95 % CI) was 15.86 (14.17-17.76) for both cities and was particularly increased in younger individuals, females, those injecting daily, not enrolled to opioid agonist treatment and HIV-infected individuals. Older age, living in Thessaloniki, Greek origin, homelessness, history of injection in the past 12 months, and HIV infection were independently associated with higher risk of death. CONCLUSION: Mortality among PWID in the two largest cities (Athens and Thessaloniki) in Greece in 2018-2022 was high, with the population in Thessaloniki being particularly affected. The increasing trend in mortality in Athens may reflect the long-term impact of the COVID-19 pandemic. Preventive programs such as take-home naloxone, screening and treatment for HIV, are urgently needed.