In sub-Saharan Africa’s endemic areas for urogenital schistosomiasis, male genital schistosomiasis (MGS) can cause significant morbidity. As part of the Hybridization in UroGenital Schistosomiasis investigation, an MGS sub-study examined a cohort of adult men over a calendar year to better ascertain general infection dynamics and putative zoonotic schistosome transmission. During follow-up, demographic, health and socio-economic data were collected through individual questionnaire interviews. Collected urine and semen were analysed using urine filtration, urine and semen microscopy and molecular DNA analyses of semen. Ten participants with reported MGS-associated symptoms had Schistosoma eggs in their urine and semen at 6-month follow-up, with seven at 12 months. Ten out of 11 participants with Schistosoma haematobium eggs on semen microscopy at baseline had persistent infection at 6-month follow-up, together with 6 new participants, giving an MGS prevalence of 84·2% (n = 19). Two also had Schistosoma mattheei eggs co-infection. Four of the 13 participants at 12-month follow-up had S. haematobium eggs in their semen which were persistent at all the time points. Using semen PCR, 14 participants (73·7%) had Schistosoma infection at 6 months, with only 2 participants being infected for first time. Upon DNA analysis, three participants also had hybrid co-infection at this time point. At 12 months, only 6 participants had Schistosoma infection with no hybrids detected. In summary, like S. haematobium and despite praziquantel treatment, both zoonotic and hybrid schistosomes can continue to cause MGS, which pose a further tangible challenge in future management and control measures.

We provide an update on diagnostic methods for the detection of urogenital schistosomiasis (UGS) in men and highlight that satisfactory urine-antigen diagnostics for UGS lag much behind that for intestinal schistosomiasis, where application of a urine-based point-of-care strip assay, the circulating cathodic antigen (CCA) test, is now advocated. Making specific reference to male genital schistosomiasis (MGS), we place greater emphasis on parasitological detection methods and clinical assessment of internal genitalia with ultrasonography. Unlike the advances made in defining a clinical standard protocol for female genital schistosomiasis, MGS remains inadequately defined. Whilst urine filtration with microscopic examination for ova of Schistosoma haematobium is a convenient but error-prone proxy of MGS, we describe a novel low-cost sampling and direct visualization method for the enumeration of ova in semen. Using exemplar clinical cases of MGS from our longitudinal cohort study among fishermen along the shoreline of Lake Malawi, the portfolio of diagnostic needs is appraised including: the use of symptomatology questionnaires, urine analysis (egg count and CCA measurement), semen analysis (egg count, circulating anodic antigen measurement and real-time polymerase chain reaction analysis) alongside clinical assessment with portable ultrasonography.