Hepatitis C seroprevalence and associated factors among people who inject drugs (PWID) in Estonia

Hepatitis C virus (HCV) infection causes serious liver diseases which may lead to liver failure or hepatocellular carcinoma. Due to risky injecting and sexual behavior PWIDs are at high risk for HCV. Our aim was to investigate the seroprevalence and associated factors of HCV-RNA positivity among PWIDs in Estonia.

Participants were enrolled from two RDS studies in Estonia: Tallinn 2018 and in Narva 2019. HIV and HCV (HCV-RNA and antibodies) were detected from blood sample and data from questionnaires were used to assess risk-behaviour. Logistic regression was used to calculate adjusted odds ratios (AOR) with 95% confidence intervals (CIs).

Of 459 PWIDs were 75% males, and were of 36 (median) years. Of all respondents, 79% (362/459) have ever been tested for HCV. Of those tested, 72% (262/362) were tested HCV+ (self-report). Of those tested HCV+, 43% (n=109) were offered HCV antivirals, and 49 (19%) started treatment.

At the study participation, 44% (n=204) PWID tested positive for HCV-RNA and 83% (n=379) tested positive for HCV antibodies. 52% (n=240) tested positive for HIV antibodies. Of those PWID, reporting previous HCV antiviral treatment, 45% (22/49) were HCV-RNA negative. Of those previously tested HCV-, 28% (n=28) were HCV-RNA positive.

HCV-RNA positivity was associated with HIV seropositivity (AOR=1.9, 95%CI 1.2−3.2) and imprisonment (AOR=1.8, 95%CI 1.1−3.0). But no relationship was found between gender, age, daily injecting, ≥2 sexual partners during last 12 months.

PWIDs should be considered a priority for HCV antiviral treatment due to high HCV-RNA prevalence and continuing risk for onwards transmission. Low engagement of treatment among PWIDs warrants further attention with increasing availability of short-term and more efficacious regimens.