Development of a Biosensor-Based Rapid Urine Test for Detection of Urogenital Schistosomiasis.

Schistosomiasis affects up to 300 million people in regions of South America, Southeast Asia, the Middle East, Mediterranean Europe, and sub-Saharan Africa. Chronic consequences of schistosomiasis include anemia, physical and cognitive retardation in children, and organ failure. With predilection for the genitourinary tract, Schistosoma haematobium increases the risk of bladder cancer and HIV infection in women. Microscopic identification and enumeration of parasite eggs in urine (S. haematobium) or stool (Schistosoma mansoni and Schistosoma japonicum) has remained the standard for schistosomiasis diagnosis [1]. Limitations of microscopy include the need for skilled personnel in the field with microscopy equipment and its time-consuming nature. Particularly in infrastructure-limited regions, point-of-care (POC) molecular diagnostics hold the potential to transform the management of infectious diseases such as schistosomiasis that carry significant long-term morbidity if left undiagnosed. POC diagnosis could allow selective drug administration to individuals with confirmed infection rather than entire schools or communities, and an integrated diagnosis–single dose therapy approach could reduce costs of drug administration campaigns and minimize treatment-associated adverse effects. Electrochemical biosensors are well suited for molecular diagnostics because of their high sensitivity, low cost, ease of integration into POC devices, and portability of the reader instrumentation [2]. We have developed a strategy for rapid (one hour) molecular diagnosis of bacterial urinary tract infections using electrochemical biosensors [3,4]. Urinary cells are lysed and directly applied to an array of sensors functionalized with oligonucleotide probes targeting the 16S ribosomal RNA (rRNA) of common uropathogens [3,4]. Formation of the sequence-specific hybridization complex between the pathogen rRNA and the labeled capture and detector probe pairs is detected by an enzyme tag that mediates an amperometric signal output (Fig 1). Fig 1 Biosensor-based molecular detection of urinary pathogen. In this work, we demonstrate the use of our biosensor-based platform for detection of S. haematobium in urine. We developed capture and detector probes targeting S. haematobium rRNA and integrated them into our established molecular diagnostics strategy. After determining an efficient egg lysis strategy, we demonstrated direct electrochemical detection of S. haematobium eggs spiked in human urine.