Diagnostic performance evaluation of ParaEgg for identifying intestinal helminthiasis: A comparative study with conventional copromicroscopy.

Abstract

<h4>Background</h4>Intestinal helminthiasis remains a significant public health concern in Bangladesh, affecting both humans and animals. Conventional copromicroscopic methods, though widely used, often lack sensitivity, particularly in areas with low prevalence and intensity of infection. ParaEgg, a new diagnostic tool, has been developed to improve the efficiency of copromicroscopic detection. This study aimed to evaluate the diagnostic performance of ParaEgg in detecting intestinal helminth infections in humans and dogs compared to commonly used traditional methods.<h4>Methods</h4>A cross-sectional study was conducted from August to November 2024, analyzing 100 human stool samples and 100 dog fecal samples. For human samples, ParaEgg was compared with Formalin-Ether Concentration Technique (FET), Sodium Nitrate Flotation (SNF), Harada Mori Technique (HM), and Kato-Katz Smear (KK). For animal samples, ParaEgg was evaluated against FET, SNF, and HM. Diagnostic performance was assessed using sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), with the composite results of all methods serving as the gold standard. Additionally, ParaEgg's efficacy was evaluated using naturally infected and experimentally seeded (<i>Trichuris</i> and <i>Ascaris</i> eggs) fecal samples.<h4>Results</h4>The overall helminth infection rates were 24 % in humans and 53 % in dogs. In humans, five types of helminth genera (<i>Ascaris, Trichuris, Enterobius, hookworm, and Hymenolepis</i>) were detected, while six genera (<i>Toxocara, Trichuris, Spirometra, hookworm, Alaria, and Hymenolepis</i>) were identified in dogs. In human, ParaEgg detected 24 % of positive cases, closely following Kato-Katz Smear (26 %) and outperforming FET (18 %), SNF (19 %), and HM (9 %). In animal samples, ParaEgg demonstrated superior performance, identifying 53 % of positive cases compared to FET (48 %), SNF (45 %), and HM (29 %). ParaEgg exhibited a sensitivity of 85.7 % and specificity of 95.5 %, closely matching Kato-Katz Smear (sensitivity: 93.7 %, specificity: 95.5 %). Its NPV (80.1 %) and PPV (97.1 %) further confirmed its diagnostic reliability. In experimentally seeded samples, ParaEgg achieved 81.5 % recovery for <i>Trichuris</i> eggs and 89.0 % for <i>Ascaris</i> eggs.<h4>Conclusion</h4>These findings highlight ParaEgg as an effective diagnostic tool, comparable to Kato-Katz Smear and superior to traditional methods. Its ability to detect mixed infections, egg recovery rate and its high sensitivity in both human and animal samples underscore its potential for widespread application in field settings.