Lucy Platt ^1*, Tim Rhodes ¹, Ali Judd ¹, Evgeniya Koshkina ², Svetlana Maksimova ³, Natalia Latishevskaya ⁴, Adrian Renton ¹, Tamara McDonald ⁵, John V. Parry ⁵

¹ Imperial College
² National Research Centre on Addiction
³ Altai Krai State University
⁴ Volgograd Medical Academy
⁵ Health Protection Agency

^* To whom correspondence should be addressed. E-mail: l.platt{at}imperial.ac.uk.

	Abstract

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 <em>Treponema pallidum</em>. Associations between presence of antibodies to <em>T pallidum</em> and covariates were explored. Results. Overall, the prevalence of antibodies to <em>T pallidum</em> 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.

Key Words: Epidemiology, HIV/AIDS, Sexual Health, Surveillance, Surveys, Drugs