Evaluation and Comparison of Two Commercial Enzyme-Linked Immunosorbent Assay Kits for Detection of Antigenically Diverse Human Noroviruses in Stool Samples

Abstract

Two recently commercialized enzyme-linked immunosorbent assay kits, the SRSV(II)-AD (Denka Seiken Co. Ltd., Tokyo, Japan) and IDEIA NLV (DakoCytomation Ltd., Ely, United Kingdom) kits, that detect human norovirus (HuNV) antigens in stool samples were evaluated to assess whether they could be used instead of reverse transcription-PCR (RT-PCR) for routine diagnosis. The sensitivities and specificities of the two kits were tested with a panel of 103 stool samples containing HuNVs of 4 and 10 genetic subgroups within genogroups I and II (GI and GII), respectively, and 39 stool samples containing other enteric viruses. The Denka kit had a high sensitivity (>70% for 10 of the 14 subgroups) but a specificity of only 69%, and the Dako kit had a low sensitivity (<30% for 6 GII subgroups) but a high specificity of 100%. Statistical analysis suggests that HuNVs of four subgroups (subgroups GII/2, GII/5, GII/6, and GII/n) are likely to elude detection by the Dako kit. The two kits also demonstrated differences in reactivities. While the Dako kit discriminated between the GI and GII antigens of HuNVs, the Denka kit cross-reacted with samples containing all GI and GII subgroups of HuNVs. Moreover, the Denka kit also reacted with samples containing human sapovirus (HuSV). We demonstrate that the cross-reactivity of the Denka kit is not due to specific reactions with HuNV and HuSV antigens. These results indicate that neither the Denka kit nor the Dako kit has all the performance characteristics required to replace the RT-PCR methods used to detect HuNVs.

Apparently non-specific results found using a norovirus antigen immunoassay for fecal specimens from neonates

“…13 In addition the gut flora in neonates and especially premature neonates could differ from infants and adults, thus explaining discrepancies between the DAKO kit's evaluation trials and our results, 14 but this explanation is unlikely given that this test is licensed for use in humans, including neonates. Based on the data described above, we question the high specificity of certain norovirus antigen EIA suggested in published investigations, 7,15 particularly considering the consequences, that is, the cost and logistic problems caused by the hygienic measures such as ward closures resulting from positive NoV results. We call for studies into the specificity of these tests for norovirus detection in stool samples from neonates.…”

“…Recent findings by the Centre for Disease Control (Atlanta, USA) showed a specificity of 100% and a sensitivity of only 39% for the norovirus antigen EIA (DAKO) using highly RT-PCR-positive reference samples of genogroup I and II NoV. Interestingly, four subgroups of NoV genogroup II were not detectable by the DAKO kit. 7 In addition another study in hospitalized children evaluating two commercial EIAs found sensitivity and specificity to be 76.9% and 85.9% when compared with RT-PCR. 10 Other reports showed a high molecular diversity and multiple mutations during outbreaks in the United Kingdom or Japan.…”

“…5 In 2001, an enzyme immunoassay (EIA) has become commercially available and is intended to facilitate diagnosis of this viral infection. 5,7 According to the manufacturer this test is licensed for humans, neonates are not excluded.…”

Porcine enteric caliciviruses: Genetic and antigenic relatedness to human caliciviruses, diagnosis and epidemiology

“…Recently, two commercial ELISA kits for detection of NoVs in stool samples have been evaluated with a panel of 103 stool samples containing 4 genotypes of GI and 10 genotypes of GII NoVs and 39 stool samples containing other enteric viruses [96]. The sensitivities and specificities of the two kits were tested.…”

Noroviruses as a Cause of Nonbacterial Gastroenteritis

“…Norovirus can infect and replicate in a physiologically relevant 3-dimensional, organoid model of human small intestine epithelium [15]. Enzyme linked immunosorbent assay could be used for the screening of stool samples for NoV because of its simplicity [16]. Recently realtime reverse transcription-PCR was used for detection of GI and GII NoV from stool samples using Taq Man probes [17,18] or SYBR Green [19].…”