Effects of sex work on the prevalence of syphilis among injection drug users in 3 Russian cities.

OBJECTIVES: We examined risk factors for syphilis infection among injection drug users in 3 Russian Federation cities, focusing particular attention on the potential roles of gender and sex work. METHODS: We conducted a cross-sectional survey of injection drug users in Moscow, Volgograd, and Barnaul, collecting behavioral data and testing for antibodies to Treponema pallidum. Associations between presence of antibodies to T pallidum and covariates were explored. RESULTS: Overall, the prevalence of antibodies to T pallidum was 11% (95% confidence interval=9.7%, 13.1%). Syphilis was associated with involvement in sex work and with gender in Moscow and Barnaul but not in Volgograd. Female injection drug users not involved in sex work were more likely than men to be younger and to have recently begun to inject; female injection drug users involved in sex work were more likely than those not involved in sex work to inject daily. CONCLUSIONS: Syphilis transmission dynamics varied by region. Sex work can increase syphilis risk among injection drug users, potentially feeding the momentum of sexually transmitted HIV and syphilis among noninjectors. Targeted interventions are needed to reduce both sexual and injection risk behaviors among injection drug users.

Prevalence of HIV, hepatitis C and syphilis among injecting drug users in Russia: a multi-city study.

OBJECTIVES: To estimate the prevalence of HIV, hepatitis C virus (HCV) and syphilis in injecting drug users (IDUs) in Russia. METHODS: Unlinked anonymous cross-sectional survey of 1473 IDUs recruited from non-treatment settings in Moscow, Volgograd and Barnaul (Siberia), with oral fluid sample collection for HIV, HCV antibody (anti-HIV, anti-HCV) and syphilis testing. RESULTS: Prevalence of antibody to HIV was 14% in Moscow, 3% in Volgograd and 9% in Barnaul. HCV prevalence was 67% in Moscow, 70% in Volgograd and 54% in Barnaul. Prevalence of positive syphilis serology was 8% in Moscow, 20% in Volgograd and 6% in Barnaul. Half of those HIV positive and a third of those HCV positive were unaware of their positive status. Common risk factors associated with HIV and HCV infection across the cities included both direct and indirect sharing of injecting equipment and injection of home-produced drugs. Among environmental risk factors, we found increased odds of anti-HIV associated with being in prison in Moscow, and some association between official registration as a drug user and anti-HIV and anti-HCV. No associations were found between sexual risk behaviours and anti-HIV in any city. CONCLUSIONS: HIV prevalence among IDUs was markedly higher than city routine surveillance data suggests and at potentially critical levels in terms of HIV prevention in two cities. HCV prevalence was high in all cities. Syphilis prevalence highlights the potential for sexual risk and sexual HIV transmission. Despite large-scale testing programmes, knowledge of positive status was poor. The scaling-up of harm reduction for IDUs in Russia, including sexual risk reduction, is an urgent priority.

Evaluation of a modified commercial assay in detecting antibody to hepatitis C virus in oral fluids and dried blood spots.

Oral fluid testing is an effective alternative to serum antibody testing for surveillance of human immunodeficiency virus (HIV) and hepatitis B infections, and is being extended to hepatitis C infections. The objective of this study was to determine and compare the sensitivity and specificity of a modified commercial assay for the detection of antibody to hepatitis C virus (anti-HCV) in oral fluids collected by two different oral fluid collection devices (the Epitope OraSure trade mark and Sarstedt Salivette ) and in dried fingerprick blood spots. In this study, 253 anti-HCV seropositive patients and 394 blood donors (all anti-HCV negative) were recruited between August 2000 and January 2001. Each participant provided oral fluid specimens by OraSure and Salivette, and at least one dried blood spot. Serum specimens were collected from the patients whenever possible. For those injecting drug users who did not provide a serum specimen, HCV status was established on the basis of previous testing. All the nonserum samples were tested for the presence of anti-HCV, using a modified Ortho HCV 3.0 SAVe enzyme-linked immunosorbent assay (ELISA) protocol. The recommended preliminary cutoffs for the modified ELISA were suboptimal. Further, the sensitivity, specificity, and positive and negative predictive values could be improved by varying the cutoff and taking into account the likely prevalence of HCV in the population under investigation. For instance, given a population with a 50% prevalence of anti-HCV, the optimal sensitivities of the modified assay on OraSure, Salivette, and dried blood spots were 92%, 83%, and virtually 100%, respectively, in contrast to 83%, 59%, and 99% using the preliminary cutoffs. The respective optimal specificities were 99%, 93%, and 100%. In conclusion, oral fluids collected by the OraSure device provide an extremely useful method to conduct public health surveillance of not only HIV, but also hepatitis C, among injecting drug users. In addition, dried blood spot specimens may be useful for surveillance and could be employed as a first line diagnostic specimen.