 |
|
|
| |
German Gays
|
| |
| |
3rd International Workshop on HIV Transmission:
Principles of Intervention
July 31-August 2, 2008, Mexico City
Mark Mascolini
Sexually transmitted infections (STIs), especially syphilis, may lie behind rising rates of HIV transmission among gay German men, according to results of a national study involving men tested for HIV from 2001 through 2007 [1]. The investigators believe their findings cast doubt on the value of wider HIV testing as the sole tactic for stemming a growing HIV epidemic among gays.
HIV rates have climbed among gay Germans since 2001, as they have among gays in other developed countries. Some evidence suggests that just-infected adults with high HIV loads account for a disproportionate share of HIV transmissions. As a result, some public health authorities argue that wider HIV testing can slow further spread of HIV by diagnosing more infection at this early stage.
Because coinfection with HIV and other sexually transmitted pathogens may also heighten the risk of HIV transmission--and may do so over a longer period than acute HIV infection--Ulrich Marcus (Robert Koch Institute, Berlin) and coworkers tracked rates of syphilis and HIV infection across all 95 German postal code regions from 2001 through 2007. Recent studies show correlations between syphilis and HIV infection among gay men in other high-income countries, including the United States [2,3].
Marcus and coworkers found a strong link between new syphilis diagnoses (incidence) and new diagnoses of HIV among gay men throughout Germany: Most regions with high syphilis incidence also had a high HIV incidence, and most regions with low incidence of one infection had low incidence of the other. Jumps or dips in syphilis incidence tended to precede or parallel changes in HIV incidence.
The proportion of HIV-infected men diagnosed with syphilis rose from 5% to 2001-2003 to 9% in 2004-2007. Gay men diagnosed with syphilis in the past year who also had their most recent HIV test in the past 18 months had almost a 7 times higher risk of testing positive for HIV than men without syphilis (odds ratio 6.8, 95% confidence interval 4.5 to 10.2). For men between 30 and 44 years old, that heightened risk rose to 8.6-fold (95% confidence interval 5.0 to 10.7).
The study also suggested that "serosorting" (having sex only with men who have the same HIV status) may paradoxically hasten HIV's spread among gay men. Marcus found that syphilis had a bigger impact on HIV incidence in regions with lower HIV prevalence. That finding, he proposed, "may be a consequence of HIV-negative serosorting, which leads to rapid dissemination of HIV once HIV-negative serosorters become (unknowingly) infected with HIV." At the same time, serosorting between partners who already know they have HIV may further spread of non-HIV STIs.
In 2006 a 6651-man survey showed that gay HIV-infected Germans not yet taking antiretroviral therapy had higher new-diagnosis rates of bacterial STIs (such as syphilis) than men taking antiretrovirals. The untreated men also had more sexual partners and more episodes of unprotected anal intercourse with uninfected men or men of unknown HIV status.
Among men with syphilis, Marcus and colleagues proposed, risk of HIV transmission may be as high as it is during early weeks of HIV infection. If high STI rates in antiretroviral-naive HIV-infected men and in HIV-uninfected men do drive increasing transmission in gays, Marcus suggested "a broader sexual health approach will be needed" to slow HIV's spread among these men. "A narrow focus on HIV-testing campaigns," he argued, "may not be sufficient."
Marcus stressed that additional factors not considered in his analysis--such as use of Viagra or crystal meth and easy contact with anonymous partners over the Internet--also undoubtedly contribute to evolving dynamics of HIV incidence in gay populations like this one.
References
1. Marcus U, Schmidt AJ, Hamouda O. Driving forces of increasing HIV transmission in German MSM. 3rd International Workshop on HIV Transmission: Principles of Intervention. July 31-August 2, 2008, Mexico City. Abstract 13.
2. Buchacz K, Klausner JD, Kerndt PR, et al. HIV incidence among men diagnosed with early syphilis in Atlanta, San Francisco, and Los Angeles, 2004 to 2005. J Acquir Immune Defic Syndr. 2008;47:234-240.
3. Centers for Disease Control and Prevention (CDC). Symptomatic early neurosyphilis among HIV-positive men who have sex with men--four cities, United States, January 2002-June 2004. MMWR Morb Mortal Wkly Rep. 2007;56(25):625-628.
|
| |
|
|
|
|
|
