Prevalence and Incidence of Syphilis Among South American Transgender Sex Workers in Northern Italy

Abstract

To the Editor: Sex workers (SWs) constitute a core group that are known to be highly vulnerable to sexually transmitted infections (STIs) and HIV.1 The number of migrant men and women engaging in prostitution has increased in the past few years in Italy, especially in the northern regions.2 Migrant SWs are unregistered because prostitution is a nonregulated activity in Italy. They are often socially stigmatized and economically disadvantaged, have limited access to health services, and are difficult to reach by information campaigns. Transgender SWs have been reported as a group with a particularly high prevalence and incidence of HIV,3 but limited data are available on other STIs in this population. We describe here the prevalence and incidence of syphilis and HIV among South American male to female (MTF) transgender persons in Brescia, Northern Italy. These persons are phenotypically women and their gender self-identification is female, but none has had surgery. Their clients are male in gender, are not homosexuals, and they are definitely aware they are engaging in sex with a MTF transgender SW. We retrospectively analyzed the clinical charts at the sexually transmitted disease clinic in Brescia. The clinic is the only public health structure providing free and anonymous counseling and testing for HIV and STIs in the District of Brescia and is therefore the reference centre for undocumented SWs. We performed chart abstraction of all persons who 1) were male to female transgender, 2) had identified themselves as SWs, 3) had at least one syphilis serology result, and 4) were foreign-born persons from South America. A prevalent case of active syphilis was defined as a person with a reactive Treponema pallidum hemagglutination (TPHA) and rapid plasma reagin (RPR) test. An incident syphilis case was defined as a person with a nonreactive TPHA serology at baseline with a reactive TPHA and RPR serology at follow up. From April 2002 to January 2004, 86 eligible cases were identified. Their mean age was 27.8 years, 91% were from Brazil, and 9% were from Colombia. Regular condom use with clients was reported by 79%. Twelve prevalent cases of syphilis were identified (14.0%). They were all classified as latent syphilis cases. None presented with concomitant gonococcal or chlamydial infection. In addition, 15 clients had a positive TPHA but a negative RPR. The HIV test was accepted by 85 subjects; 23 of them were positive (27.1%). The proportion of HIV-infected persons was 42.3% (11 of 26) among those with a positive TPHA test, and 20.3% (12 of 59) among those with a negative TPHA test (odds ratio = 2.87, confidence interval = 0.94–8.85, P <0.04). Of the 59 subjects who were initially TPHA-negative, 19 were reevaluated 6 months or more after the first evaluation and had repeated tests for HIV and syphilis; syphilis incidence was measured in this retrospective cohort. Five incident cases of syphilis were identified during a mean follow-up period of 24.1 months for an incidence rate of 13.1 per 100 person per year. No HIV seroconversion was observed. Our date suggest high incidence of syphilis among MTF transgender prostitutes in Italy and add to the evidence of a reemergent syphilis epidemic among men who exchange money for sex in the United States,4 the United Kingdom,5 and Italy.6 Increasing rates of syphilis raise concern about the potential increase in HIV incidence; the former is an early indicator of resurgence of risky sexual behaviors and HIV transmission and acquisition.7 In addition, because the clients of MTF transgender SWs are not homosexual men, a potential bridge to the heterosexual population can be established. This study has several limitations; first, the retrospective design; second, the nonrandom sampling of transgender subjects both at baseline and at follow up; and third, the small number of subjects both at baseline and follow up. However, collection of exhaustive epidemiologic data from transgender SWs is difficult because of the clandestine status and mobility. Despite these limitations, our data identify foreign-born transgender SWs and their clients as a group at very high risk for syphilis and potentially HIV. Control of HIV and STIs should include the provision of accessible and appropriate health services for foreign-born MTF transgender persons by the provision of testing, care, targeted education, and social support. Beyond this, efforts are warranted to disrupt the association between increased risk for STIs and stigmatization/marginalization of MTF transgender persons; such association is perpetuated by the difficulties in maintaining stable relationships, obtaining stable income, and coping with financial requirements for hormone therapy and surgical modifications.8