Comparative Performance Evaluation of The OV-Rapid Diagnostic Test, Modified Kato-Katz Technique, and Formalin Ethyl-acetate Concentration Technique for The Detection of Opisthorchis Viverrini Infection in Health Region 7 Area in 2022

Abstract

This study compares the performance of three methods for detecting Opisthorchis viverrini infection: the OV-Rapid diagnostic test (OV-RDT), the modified Kato-Katz technique (MKKT), and the formalin ethyl-acetate concentration technique (FECT), in various regions with varying prevalence rates. The study population in Health District 7 consisted of adults over 15 in the provinces of Khon Kaen, Mahasarakham, Kalasin, and Roi Et, totaling 2,628 individuals in the sample. The effectiveness of the three test methods was assessed in May 2022 using descriptive statistics, including number, percentage, average, standard deviation, and analytical statistics: sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

Among the 2,628 individuals, 1,644 were females (62.60%). The age distribution showed 1,309 individuals in the 46–60 years age range (48.80%). The distribution across provinces included 585 cases in Khon Kaen (22.26%), 560 cases in Mahasarakham (21.31%), 764 cases in Roi Et (29.08%), and 719 cases in Kalasin (27.35%). The mean egg per gram of feces (MEPG) revealed the density of liver fluke infection using the MKKT method, with Roi Et at 63.89, Khon Kaen at 69.87, Mahasarakham at 130.33, and Kalasin at 69.87. FECT showed Roi Et at 107.89, Khon Kaen at 10.05, Mahasarakham at 68.69, and Kalasin at 45.62 with O. viverrini infection density.

The MKKT test method found an infection rate of 8.52%, sensitivity of 32.00%, specificity of 100%, positive predictive value of 100.00%, negative predictive value of 80.20%, and accuracy of 81.89%. The OV-RDT test found an infection rate of 15.83%, sensitivity of 59.43%, specificity of 100.00%, positive predictive value of 100%, negative predictive value of 87.16%, and accuracy of 89.19%. The FECT test found an infection rate of 7.27%, sensitivity of 27.29%, specificity of 100%, positive predictive value of 100.00%, negative predictive value of 79.11%, and accuracy of 80.63%.

Analysis of the comparative fluke examination process and cost revealed the duration of the fluke examination, including Step 1: Community readiness, Step 2: Sample preparation, Step 3: Sample analysis, and Step 4: Result reporting. Each technique required the same amount of time for community readiness and sample collection. Differences arose in the sample analysis process, where MKKT, FECT, and OV-RDT required 45, 60, and 10 minutes, respectively. During community planning and sample collection, variations occurred in the sample analysis procedure. The cost analysis showed fees for MKKT, FECT, and OV-RDT tests ranging from 22.05 to 30.87 Baht per sample.