Rapid Decline in HIV Incidence Among Persons Who Inject Drugs During a Fast-Track Combination Prevention Program After an HIV Outbreak in Athens

Abstract

Background: A "seek-test-treat" intervention (ARISTOTLE) was implemented in response to an outbreak of human immunodeficiency virus (HIV) infection among persons who inject drugs (PWID) in Athens. We assess trends in HIV incidence, prevalence, risk behaviors and access to prevention/treatment.

Methods: Methods included behavioral data collection, provision of injection equipment, HIV testing, linkage to opioid substitution treatment (OST) programs and HIV care during 5 rounds of respondent-driven sampling (2012-2013). HIV incidence was estimated from observed seroconversions.

Results: Estimated coverage of the target population was 88% (71%-100%; 7113 questionnaires/blood samples from 3320 PWID). The prevalence of HIV infection was 16.5%. The incidence per 100 person-years decreased from 7.8 (95% confidence interval, 4.6-13.1) (2012) to 1.7 (0.55-5.31) (2013; P for trend = .001). Risk factors for seroconversion were frequency of injection, homelessness, and history of imprisonment. Injection at least once daily declined from 45.2% to 18.8% (P < .001) and from 36.8% to 26.0% (P = .007) for sharing syringes, and the proportion of undiagnosed HIV infection declined from 84.3% to 15.0% (P < .001). Current OST increased from 12.2% to 27.7% (P < .001), and 48.4% of unlinked seropositive participants were linked to HIV care through 2013. Repeat participants reported higher rates of adequate syringe coverage, linkage to HIV care and OST.

Conclusions: Multiple evidence-based interventions delivered through rapid recruitment in a large proportion of the population of PWID are likely to have helped mitigate this HIV outbreak.

Keywords: HIV; PWID; combination prevention.; incidence; outbreak; prevalence; testing.

© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Figures

Figure 1.

Human immunodeficiency virus (HIV) prevalence per round among persons who inject drugs participating in ARISTOTLE (respondent-driven sampling–weighted estimates with 95% confidence intervals).

Figure 2.

Number of reported human immunodeficiency virus (HIV) type 1 cases per month in Greece (vertical bars), incidence of HIV-1 infection (solid black line), and timing of ARISTOTLE and other interventions (January [Jan] 2010 April 2013). Boosts in needle and syringe programs (NSPs) and opioid substitution treatment (OST) included increased numbers of centers providing OST and initiatives of the Greek Organisation Against Drugs in cooperation with the Hellenic Centre for Disease Control and Prevention and nongovernmental organizations to scale up NSPs. Jul, July; Mar, March; Nov, November; Sep, September.

Figure 3.

Access to prevention and linkage to human immunodeficiency virus (HIV) care during ARISTOTLE. A, Proportion of persons who inject drugs (PWID) reporting currently receiving opioid substitution treatment (OST), proportion reporting adequate syringe coverage in the past month (ie, receiving as many or more syringes in a month as they needed for their frequency of injection), and proportion of HIV-1–positive PWID reporting being undiagnosed per round (respondent-driven sampling–weighted estimates). B, Cumulative proportion of previously unlinked HIV-positive PWID who were linked to HIV care and started highly active antiretroviral therapy (HAART) by the end of each round (unweighted estimates from data collected directly through infectious diseases units).