November 15, 2010

Study examines risk of hetero HIV transmission in China

Since 2007, heterosexual transmission has replaced injecting drug use as the primary transmission mode of all HIV infections in China, and a new study by researchers at the Johns Hopkins Bloomberg School of Public Health examines the burden of HIV and sexually transmitted disease among male clients of the commercial sex industry in that country’s Sichuan province.

The study is available online in advance of publication in the journal Sexually Transmitted Infections.

“We found a large burden of syphilis infection coupled with high-risk sexual and substance use behaviors among male clients of sex workers,” said Cui Yang, lead author of the study and a postdoctoral fellow in the Bloomberg School’s Department of Epidemiology. “Without effective interventions to prevent HIV transmission to the male client population, the current epidemic may expand into the general population.”

For the study, Yang and her colleagues examined the prevalence of HIV, syphilis and hepatitis C virus in a sample of 600 male clients of female sex workers in three urban areas in Sichuan province. Blood test results indicated that HIV prevalence was 1.5 percent; 5.3 percent were positive for syphilis and 8.7 percent positive for hepatitis C virus. The overall prevalence of consistent condom use with female sex workers was 30 percent. The study also found a significant correlation between syphilis infection among male clients and not having local household registration, snorting heroin and washing genitals after having sex with a female sex worker.

Kenrad Nelson, senior author of the study and a professor in the Department of Epidemiology at the Bloomberg School, said, “Our data raises concerns about the future heterosexual transmission of HIV to the general population in China since unprotected sex with female sex workers has become the norm.”

Additional authors of the study are Carl Latkin and Cunling Wang, both of Johns Hopkins; and Rongsheng Luan, of the West China School of Public Health at Sichuan University.

The research was funded by a grant from the National Institute of Allergy and Infectious Diseases.