Public Health Briefs and AIDS risk. Am Behav Scientist. 1990;33: 465-477. 11. Donoghoe MC, Dolan KA, Stimson GV. Life-style factors and social circumstances of syringe sharing in injecting drug users. Br J Addict. 1992;87:993-1003. 12. Booth RE, Watters JK, Chitwood DD. HIV risk-related sex behaviors among injection drug users, crack users, and injection drug users who smoke crack. Am J Public Health. 1993;83: 1144-1 148. 13. McBride DC, Inciardi JA, Chitwood DD, McCoy CB, National AIDS Research Consor- tium. Crack use and correlates of use in a national population of street heroin users. J Psychoactive Drugs. 1992;24:411-416. 14. Des Jarlais DC, Wenston J, Friedman SR, Sotheran JL, Maslansky R, Marmor M. Crack cocaine use in a cohort of methadone mainte- nance patients. J Subst Abuse Treat. 1992;9: 319-325. 15. Wolfe H, Vranizan KM, Gorter RG, Keffelew AS, Moss AR. Crack use and human immuno- deficiency virus infection among San Fran- cisco intravenous drug users. Sex Transm Dis. 1992; 19:111-1 14. 16. Iguchi MY, Bux DA, Lidz V, Kushner H, French JF, Platt JJ. Interpreting HIV seropreva- lence data from a street-based outreach pro- gram. J Acquir Immune Defic Svndr: 1994;7: 491-499. 17. Blower SM, McLean AR. Mixing ecology and epidemiology. Proc R Soc Lond [Biol]. 1991; 245:187-192. 18. Morris M. Epidemiology and social networks: modeling structured diffusion. In: Wasserman S, Galaskiewicz J, eds. Advances in Social NetworkAnalysis. Thousand Oaks, Calif: Sage Publications; 1994;2:26-52. 19. Needle RH, Genser SG, Trotter RT. Social Networks, Drug Abuse, and HIV Transmission. Bethesda, Md: National Institutes of Health; 1995. NIDA research monograph 151, NIH publication 95-3889. 20. Service SK, Blower SM. HIV transmission in sexual networks: an empirical analysis. Proc R Soc Lond [Biol]. 1995;260:237- 244. Low Prevalences of HIV Infection and Sexually Transmitted Disease among Female Commercial Sex Workers in Mexico City Felipe Uribe-Salas, MD, MPH, Mauricio Hemrnandez-Avila, MD, DSc, Carlos J. Conde-Glez, PhD, MSc, Luis Jua'rez-Figueroa, MD, Betania Allen, Rafael Anaya-Ocampo, Carlos Del Rfo-Chiriboga, MD, Patricia Uribe-Zuihiga, MD, and Barbara de Zalduondo, PhD ''.:.;. fea. 6A%, 63%. - 6%, 17%, ...... ....__ .........: ... ...' ..... *:: :b: ~~~~~~~~~.: CO*tesiusiI Mos S t ...: ' <~~~~~~~~~~~~A 1.$.! .-i_3 [ ;f t 1:10 15 101 Am ria Jora of. :u i :...I...s:':.:. .:.. :,t...:. h. Introduction In Mexico, human immunodefi- ciency virus (HIV) infection initially affected homosexual and bisexual men with multiple partners. Currently, the virus is spreading to growing numbers of heterosexual individuals. The percentage of acquired immunodeficiency syndrome (AIDS) cases among women (with identi- fied risk factors) increased from 0% in 1983/84 to 14% as of January 1, 19971 2 and heterosexual transmission in women rose from 28.8% in 1989 to 53.3% as of January 1, 1997.34 However, little is known about the risks for HIV infection, as well as infection involving other sexually transmitted diseases (STDs), among female commercial sex workers in Mexico. Commercial sex in Mexico City takes place under an abolitionist system, and, according to local city laws, prostitu- tion is a misdemeanor.5 Therefore, regis- tries of workers or authorized work sites do not exist. In this report, we describe results related to several STD prevalences and their variation according to work sites in a random stratified sample of female commercial sex workers working in Mexico City. Methods During 1992, using direct observa- tion, in-depth interviews, key informants, and focus groups, we constructed a sample frame of commercial sex work sites located in an urban area of Mexico City. Types of sites identified were street comers, bars, and massage parlors. Felipe Uribe-Salas, Mauricio Hemrnndez-Avila, Carlos J. Conde-Glez, Luis Juarez-Figueroa, Betania Allen, and Rafael Anaya-Ocampo are with the National Institute of Public Health, Cuemavaca, Morelos, Mexico. Carlos Del Rio- Chiriboga and Patricia Uribe-Znfiiga are with the National Council for the Prevention and Control of AIDS, Mexico City. Barbara de Zalduondo is with the Division of HIV/AIDS, Office of Health and Nutrition, US Agency for International Development, Rosslyn, Va. Requests for reprints should be sent to Mauricio Hermnndez-Avila, MD, DSc, Centro de Investigaciones en Salud Poblacional, Instituto Nacional de Salud Publica, Av Universidad 655 Col. Sta. Ma. Ahuacatitlan, CP 62508 Cuer- navaca, Morelos, Mexico. This paper was accepted August 19, 1996. June 1997, Vol. 87, No. 6