This study was designed as an opportunistic screening to estimate the prevalence of blood-borne viral infection among drug users in treatment in the rural population and to investigate related risk factors and use of general health services. A total of 102 patients aged 18 years and over (78 male, 24 female) with problematic self-reported drug use, recruited between 1 February 1996 and 31 January 1997, in a mixed urban-rural population in south-east England, were interviewed for information on socio-demographic status, drug use history, HIV-related risk behaviours, hepatitis B vaccination, general practice consultations, and use of A&E departments and medical out-patient clinics. Diagnostic testing was offered to all patients for anti-HIV-1, anti-HBc, HBsAg and anti-HCV. The mean age at onset of illicit drug use for the entire sample was 15.33 (SD 3.36) years; 3.7 per cent (1/27), 20.4 per cent (18/88), and 55.8 per cent (48/86) had antibodies to HIV-1, HBc and HCV, respectively; 1.1 per cent (1/88) tested positive for HBsAg indicative of a carrier state. All 18 patients anti-HBc seropositive were male (p = 0.009). There was no gender difference for anti-HCV serological status. The proportion of town residents and village dwellers seropositive for anti-HBc and anti-HCV did not differ significantly. Patient's age at interview, age at onset of opioid use and duration of opioid use showed a significant association with anti-HBc and anti-HCV serological status. The proportion directly sharing injecting equipment was too small for rigorous statistical analysis; however, indirect sharing involving cooking equipment and frontloading rituals achieved statistical significance. Anti-HBc serological status showed a significant association with vaginal intercourse without a condom (p = 0.03); none of the sexual risk behaviour variables revealed any significant association with HCV infection. Although only one-third of the sample consented to HIV antibody test, consenting and non-consenting groups did not differ significantly except on one variable: having a drug-using sexual partner (chi2 = 5.6167; p = 0.017). Serum aspartate amino transferase and gamma-glutamyl transpeptidase concentrations were raised above the upper limit in 23 (25.7 per cent) of the 89 patients who gave blood specimens; 41.2 per cent (42/102) were referred to treatment by their general practitioners. There was no significant relationship between HBV and HCV serological status and general practice consultations. Only eight (7.8 per cent) had received hepatitis B vaccination, and although 48 (47.1 per cent) had in the preceding 12 months used A&E departments, only seven (6.2 per cent) had been seen in medical out-patient clinics. In this study the prevalence of HIV, HBV and HCV in the rural population is as high as has been reported for inner cities. The poor uptake of hepatitis B vaccination among drug users, their poor response to HIV antibody test and poor health service utilization suggest the need for an urgent appraisal of service provision and a review of prevention and treatment strategies.