[Comparison of efficiency of Kato-Katz technique and PCR assay for detecting infection].

Objective: To compare the performance of modified Kato-Katz thick smear method (KK method) and PCR assay in field detection of in human fecal samples, which provides insight into the selection of tools for detecting .

Methods: Based on the epidemiological investigation of human infections in Tengxian County of Guangxi Zhuang Autonomous Region in 2016, a total of 133 fecal samples were randomly selected and stored at -20 ℃. All fecal samples were detected for infection using KK method and PCR assay, and the detection rate was compared between the two techniques. In addition, test was used to evaluate the consistency between the two methods.

Results: Among all fecal samples, the overall detection rate of was 77.44% (103/133), and the detection rate was significantly higher by PCR assay (70.68%, 93/133) than by KK method (57.14%, 76/133) ( = 26.15, < 0.01). There were 88.16% (67/76) of the microscopy-positive fecal samples positive for PCR assay, and 47.37% (27/57) of the microscopy-negative fecal samples positive for PCR assay. The detection rate of by PCR assay (94.74%, 18/19) was higher in fecal samples with EPG of > 1 000 than in samples with EPG of < 1 000 (85.96%, 49/57) ( = 1.05, = 0.436). The consistency of the detection rate of was moderate between the KK method and PCR assay ( = 0.73).

Conclusions: The detection rate of by PCR assay is significantly higher than by KK method. In low-endemic areas of infections, the combination of KK method and PCR assay is suggested, so as to improve the detection rate.