HIV can still be detected in the semen of some HIV-infected men, even if they are on sustained antiretroviral therapy and have an undetectable viral load in their blood, according to a study presented at IAS 2013.
The study, conducted by French researchers and led by Jade Ghosn, Ph.D., followed 157 HIV-infected men who have sex with men (MSM), all of whom were on treatment, had a blood plasma viral load below 50 copies/mL and had no symptoms of other sexually transmitted infections (STIs).
The researchers found that 7.6% of the MSM had detectable (over 50 copies/mL) amounts of HIV in their semen. This finding was based on analyses of semen samples collected at baseline and at 4 weeks. HIV was detected in 23 out of 304 semen samples, with a median seminal plasma viral load of 145 copies/mL.
The median age of the participants was 44, with a median CD4+ cell count of 637. The median time on treatment at baseline was 6.6 years and the median time with an undetectable viral load was 3.3 years.
After performing a multivariate analysis, the researchers found no association between seminal viral load and STI, nadir or current CD4+ cell count, duration of undetectable blood viral load, adherence to treatment or number of sexual partners.
However, having HIV DNA in the peripheral blood mononuclear cells (PBMCs) above 318 copies per million cells made it 3.1 times more likely for a study participant to have detectable virus in his semen.
Also worth noting: The 7.6% rate for MSM was much higher than the 3.1% rate found in a study of heterosexual men conducted by Sidonie Lambert-Niclot, Pharm.D., Ph.D., and her team, but the researchers did not have data to explain why this difference may be.
These findings were also previously presented at ICAAC 2012.
View the full study poster.