A Comparison of Diagnostics Kits Used in Russia for Identification of Antigens of Noroviruses

Resumo

Three diagnostic kits for detection of antigens of noroviruses were evaluated and compared. These were (1) the RIDAQUICK® Norovirus test kit (R-Biopharm AG, Germany), (2) the RIDASCREEN® Norovirus test kit (R-Biopharm AG, Germany), and (3) the Norovirus-antigen IFA-BEST kit (VECTOR-BEST, Russia). The study was carried out with a panel containing 90 norovirus-positive (GI/GII) stool samples (GI.2, GI.3, GI.4, GI.6, GII.1, GII.2, GII.3 and GII.4 (including GII.4_New_Orlean and GII.4_Sydney), and GII.5, GII.6, GII.7, GII.10, GII.15. and GII.17) and 30 negative samples. The AmpliSens OKI scrin kit (FSR no. 2008/02265 dated November 17, 2011) was used as for comparison for identification of noroviruses of the GII genogroup. A technique that included confirmative sequencing of the capsid and polymerase gene fragments was used to determine noroviruses of the GI genogroup. Only 26 of 90 (28.9%) reference-positive samples were determined as norovirus-positive ones with any of the three diagnostic kits used in the present study. False-positive results of the test were revealed only with the Norovirus-antigen IFA-BEST kit in 8 out of 30 (26.7%) reference-negative samples. The estimated indices of diagnostic sensitivity and specificity of the RIDAQUICK® Norovirus test kit were 12.2 and 100%, respectively. They were 26.7 and 100% for the RIDASCREEN® Norovirus test kit and 17.8 and 73.3% for the Norovirus-antigen IFA-BEST kit.