Background: Male Genital Schistosomiasis (MGS) is hypothesized to increase seminal shedding of HIV-1 RNA. We aimed to assess the impact of MGS on genital HIV-1 RNA shedding by longitudinally measuring HIV-1 RNA levels in men established on long-term ART comparing those with and without a diagnosis of MGS.
Methods: Following optimisation of the GeneXpert® HIV-1 RNA assay for use with seminal fluid, we analysed 76 paired plasma and semen samples collected from 31 men over 12 months, comprising 15 with and 16 subjects without MGS. Study visits occurred at 0, 1, 3, 6 and 12 months. A diagnosis of schistosomiasis was based on Schistosoma positivity using eggs by microscopy of filtrated urine, semen, seminal sediment, POC-CCA test or by testing PCR of seminal sediment or urine at one or more time points. MGS was diagnosed by egg positivity on semen microscopy or PCR of seminal sediment. All subjects were blindly treated with a single dose of praziquantel at each study visit.
Results: Across the entire study population, HIV-1 RNA was detected in 7/76 (9.2%) seminal samples and 29/76 (38.2%) plasma samples. Among all participants, 5/31 (16.1%) showed HIV-1 RNA detection in one or more seminal samples, with 3/5 (60%) showing HIV-1 RNA detection in semen only with levels up to 400 copies/ml. The three subjects were in the MGS positive group. The two subjects showing HIV-1 RNA in seminal fluid from the MGS negative group also had concomitant HIV-1 RNA detection in plasma.
Conclusion: We found no notable difference in the pattern of genital shedding in the seminal compartment of HIV-1 infected men established on ART with and without a diagnosis for MGS following treatment with praziquantel.