Study suggests link between HIV therapy and syphilis outbreaks

Caroline Cameron

Drugs used to prevent and treat HIV could be contributing to a rise in syphilis cases, according to a new study co-authored by University of Victoria microbiologist Caroline Cameron. 

Syphilis cases have risen sharply in recent years, primarily affecting men who have sex with men. This increase has been attributed to more risky sexual behaviour, but the increase of syphilis is outpacing that of other sexually transmitted diseases.

The study team theorizes that this increase might be partly connected to antiretroviral medications used for treatment and prevention of HIV infection. 

The study, published today in BMJ Sexually Transmitted Infections, suggests that medications used in highly active antiretroviral therapy (HAART) for treating HIV may affect the body’s immune response to certain diseases, including syphilis.  
“HAART has been transformational in the battle against HIV,” says Cameron. “But, if further study confirms our hypothesis, we’ll have yet another reason to intensify the fight against syphilis.”