Failure of the parasitological methods to detect S. stercoralis in samples testing positive by real-time PCR may in part be due to the presence of nonviable larvae in those samples, and the necessity of the presence of living larvae in the APC method. On the other hand, the failure of real-time PCR to detect 13 cases detected by parasitological methods may be due to the low
parasitic load in the samples (11/13 cases had low infection),an effect of fecal inhibitors and competing template in
genomic DNA