If reports published in a recent study are to be believed, treatment for HIV may make patients more vulnerable to syphilis. All the gay/bisexual men who consume antiretroviral drugs to treat HIV infection may be unknowingly boosting their susceptibility to the bacteria responsible for syphilis. The findings showed that the availability of highly active antiretroviral therapy (HAART) has eliminated the fear factor, which conversely prompted higher rates of sexually transmitted infections because of risky, unprotected sex. This may explain the reason behind the rapidly increase in the rates of syphilis in gay and bisexual men over the past decade, the researchers said. “We are living in an era where [antiretroviral therapy] is being used to effectively treat and prevent HIV infection. To some extent this seems to have tempered the urgency to control other [sexually transmitted infections],” said Michael.L. Rekart from University of British Columbia, in Vancouver, Canada. But, the researchers are not clear why rates of syphilis among gay/bisexual men should be so much higher than those of other sexually transmitted infections such as chlamydia or gonorrhea. This is because HAART is known to boost immune system activity and is expected to lower susceptibility to infections. For the study, the team reviewed the impact of HAART on behavioural and immune system change.