Introduction: Prevalence of viral hepatitis A–C markers in problematic drug users was studied. Material and Methods: Two groups of drug users, i.e. addicts enrolled in a mid-term drug withdrawal community program (group 1) and penitentiary prisoners (group 2), were tested for the presence of viral hepatitis A–C markers. Group 1 of 546 addicts (335 males and 211 females) included 163 male and 91 female injection drug users (IDUs) and 172 male and 120 female mostly alcohol abusers. Group 2 of 197 male prisoners included 150 injection drug users and 47 mostly alcohol abusers. Serological markers of viral hepatitis were detected by EIA within the entry check-up; RT PCR was used for detection of HCV nucleic acid. Results: The prevalence rates of anti-HAV antibodies among group 1 addicts were 33.6% for IDUs and 39.5% for the remaining mostly alcohol abusers. HBsAg was found in 4.2% of IDUs and 0.0% in the remaining addicts. Two IDUs also tested positive for HBeAg. Anti-HCV positivity was recorded in 22.4% of IDUs and 5.6% of the remaining addicts. The prevalence rates of anti-HAV antibodies among group 2 penitentiary prisoners were 40.7% for IDUs and 28.6% for the remaning mostly alcohol abusers. Anti-HAV IgM antibodies were detected in 4.2% prisoner IDUs. HBsAg was found in 3.4% of IDUs and 6.5%in the remaining addicts. Anti-HCV positivitywas recorded in 18.1% of IDUs and 16.3% of the remaining addicts. Conclusion: The prevalence rates of the markers studied in the addicts are several times as high as in the general population; therefore, the population of addicts is a potential source of the spread of viral hepatitis.

        Key words: viral hepatitis – drug addicts.