Hepatitis C virus infection among injecting drug users in the Czech Republic -- prevalence and associated factors.

Aim: To determine the prevalence of, and factors associated with, hepatitis C virus (HCV) infection in the population of Czech injecting drug users (IDUs).

Design: Multicentric cross-sectional study.

Setting: A convenience sample of injecting drug users was recruited using the snowball sampling method.

Participants: Sample of 760 IDUs from 9 different Czech regions.

Measurement: We used one-drop instant blood tests to determine the anti-HCV antibodies status; a structured questionnaire was completed during the interview with the researcher. We calculated the ratio of positive findings and performed univariate analyses of correlations between predictors and independent variables. Finally, we created a logistic regression model that controlled for age, region of residence, reported sharing of injection paraphernalia, and length of injection drug use and for the interaction between length of injection use and imprisonment in order to assess the predictive value of imprisonment in an individual's history.

Findings: 226 participants (29.74% of the tested sample) were found to be anti-HCV positive. After adjusting for the sensitivity of the test, the 'true proportion' was 34.97% (95% CI: 31.56-38.35). Many correlated independent variables were found in the univariate analyses. In our logistic regression model, we have found that imprisonment increases the odds of being anti-HCV positive by a factor of 4.3.

Conclusion: Anti-HCV seroprevalence remains relatively low in the Czech IDUs population compared to similar populations in the developed countries. Regional differences exist in anti-HCV prevalence within the Czech Republic. The strong association of anti-HCV prevalence with imprisonment history when controlled for other potentially clinically important factors suggests the need for more effective preventive measures in Czech prisons.