AUTHOR=Mu Yi , Rivera Jonas , McManus Donald P. , Weerakoon Kosala G. , Ross Allen G. , Olveda Remigio M. , Gordon Catherine A. , You Hong , Jones Malcolm K. , Cai Pengfei 

TITLE=Comparative assessment of the SjSAP4-incorporated gold immunochromatographic assay for the diagnosis of human schistosomiasis japonica

JOURNAL=Frontiers in Public Health

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2023.1249637

DOI=10.3389/fpubh.2023.1249637

ISSN=2296-2565

ABSTRACT=<sec id="sec1"><title>Background</title><p>Schistosomiasis, a disease caused by parasites of the genus <italic>Schistosoma</italic>, remains a global public health threat. This study aimed to validate the diagnostic performance of a recently developed gold immunochromatographic assay (GICA) for the detection of <italic>S. japonicum</italic> infection in a rural endemic area of the Philippines.</p></sec><sec id="sec2"><title>Methods</title><p>Human clinical samples were collected from 412 subjects living in Laoang and Palapag municipalities, Northern Samar, the Philippines. The presence of <italic>Schistosoma</italic>-specific antibodies in serum samples was tested with the SjSAP4-incorporated GICA strips and the results were converted to fully quantitative data by introducing an <italic>R</italic> value. The performance of the established GICA was further compared with other diagnostic tools, including the Kato-Katz (KK) technique, point-of-care circulating cathodic antigen (POC-CCA), droplet digital (dd) PCR, and enzyme-linked immunosorbent assays (ELISAs).</p></sec><sec id="sec3"><title>Results</title><p>The developed GICA strip was able to detect KK positive individuals with a sensitivity of 83.3% and absolute specificity. When calibrated with the highly sensitive faecal ddPCR assay, the immunochromatographic assay displayed an accuracy of 60.7%. Globally, the GICA assay showed a high concordance with the SjSAP4-ELISA assay. The schistosomiasis positivity rate determined by the GICA test was similar to those obtained with the SjSAP4-ELISA assay and the ddPCR assay performed on serum samples (SR_ddPCR), and was 2.3 times higher than obtained with the KK method.</p></sec><sec id="sec4"><title>Conclusion</title><p>The study further confirms that the developed GICA is a valuable diagnostic tool for detecting light <italic>S. japonicum</italic> infections and implies that this point-of-care assay is a viable solution for surveying endemic areas of low-intensity schistosomiasis and identifying high-priority endemic areas for targeted interventions.</p></sec>