Visual Diagnosis in Low-Resource Settings: Evaluating Urine Color and Macroscopic Haematuria as Rapid Indicators for Schistosoma haematobium Intensity

Urinary schistosomiasis, caused by Schistosoma haematobium, remains a significant public health burden in Nigeria, particularly in rural communities with limited access to diagnostic infrastructure. While urine filtration and microscopy remain the gold standard for diagnosis, they are often impractical in low-resource field settings. This study evaluates the diagnostic performance of visual indicators—specifically, urine colour and macroscopic haematuria—as rapid, low-cost proxies for determining infection intensity. A cross-sectional study was conducted across three locations in Makurdi, Benue State: North Bank, Agwan Jukun, and Jibata. A total of 1,032 participants were recruited and screened. Urine samples were examined macroscopically for colour and haematuria, and microscopically for S. haematobium eggs. Infection intensity was categorised as light or heavy based on egg counts. Statistical associations were analysed using Chi-square tests. The overall prevalence of urogenital schistosomiasis in the study area was 56.69% (585/1,032). Visual inspection revealed a strong correlation between urine appearance and infection intensity. Participants with "Bloody Red" urine had a 99.15% infection rate, with 77.97% of these cases classified as heavy infections. Similarly, the presence of haematuria (micro and macro combined) was associated with a 97.25% infection rate, with 64.19% of these cases being heavy infections. Self-reported bloody urine also showed a high diagnostic value, with 88.76% of symptomatic individuals testing positive. Visual diagnosis, particularly the observation of bloody urine and urine colour changes, serves as a highly reliable, rapid assessment tool for identifying heavy S. haematobium infections. In resource-constrained settings where microscopy is unavailable, these visual indicators can be effectively used to prioritise treatment and map high-risk communities.