RESEARCH ARTICLE Is PCR the Next Reference Standard for the Diagnosis of Schistosoma in Stool? A Comparison with Microscopy in Senegal and

Background The current reference test for the detection of S.mansoni in endemic areas is stool micros-copy based on one or more Kato-Katz stool smears. However, stool microscopy has several shortcomings that greatly affect the efficacy of current schistosomiasis control programs. A highly specific multiplex real-time polymerase chain reaction (PCR) targeting the Schisto-soma internal transcriber-spacer-2 sequence (ITS2) was developed by our group a few years ago, but so far this PCR has been applied mostly on urine samples. Here, we per-formed more in-depth evaluation of the ITS2 PCR as an alternative method to standard microscopy for the detection and quantification of Schistosoma spp. in stool samples. Methodology/Principal findings Microscopy and PCR were performed in a Senegalese community (n = 197) in an area with high S.mansoni transmission and co-occurrence of S. haematobium, and in Kenyan schoolchildren (n = 760) from an area with comparatively low S.mansoni transmission. Despite the differences in Schistosoma endemicity the PCR performed very similarly i