Evaluation of a commercial ELISA kit for the detection of Norovirus antigens in human stool specimens

摘要

Noroviruses (NV, formerly "Norwalk-like viruses") are responsible for >85% of all nonbacterial outbreaks of gastroenteritis in Europe and are typically detected in stool by reverse transcription polymerase chain reaction (RT-PCR) or electron microscopy. More rapid and less expensive methods like the ELISA (enzyme-linked immunosorbent assay) for detection of NVs in stool samples are now commercially available. The ELISA kit IDEIA~(TM) (DakoCytomation, Ely, UK) for the detection of NV antigens in stool samples and the simultaneous determination of the NV genogroup was evaluated. The performance of the ELISA was compared with an RT-PCR by testing stool samples collected from patients involved in NV outbreaks of gastroenteritis from Switzerland and Germany. We tested 39 Swiss stool samples and found for the ELISA a sensitivity and specificity of 43 % and 83 % respectively. When tested with German stool samples, the ELISA had a sensitivity and specificity of 46% and 100% respectively. Due to its low sensitivity, the ELISA kit is unsuitable for the Swiss Cantonal Laboratories and for medical diagnostic laboratories, which mostly investigate sporadic NV cases with a small number of samples provided. The ELISA kit could be useful as a NV screening method for investigating outbreaks of gastroenteritis in institutions missing specialised molecular detection methods but having a high number of possible NV cases, for example hospitals.