ABSTRACT
@#Objective To compare the sensitivity(dilution) of antigen-detecting rapid diagnostic cards for severe acute respiratory symptom coronavirus 2(SARS-CoV-2) at home and abroad to different strains.Methods Vaccine bulks of four SARS-CoV-2 strains(original strain,Beta,Delta and Omicron) produced by Wuhan Institute of Biological Products Co.,Ltd.were used as the sample panel for sensitivity assessment,of which a series of diluted samples were detected by using 21 batches of SARS-CoV-2 antigen-detecting rapid diagnostic cards from 17 domestic and foreign manufacturers and SARS-CoV-2 nucleic acid detection reagent from Shanghai GeneoDx Biotech Co.,Ltd,respectively.The sensitivity of antigendetecting rapid diagnostic cards and nucleic acid detection reagent was evaluated according to the dilutions.The results of SARS-CoV-2 antigen-detecting rapid diagnostic reagents and nucleic acid detection reagent were compared to determine the nucleic acid detection Ct value corresponding to the group of antigen-detecting rapid diagnostic reagent with the highest dilution,namely the highest sensitivity.Results The sensitivity of antigen detection cards for the vaccine bulks of original strain,Beta,Delta and Omicron was 1:10～1:8 × 10~4.1:10~3～1:2 × 10~5,1:10~2～1:4 × 10~4,and 1:10～1:4 × 10~5,respectively;The sensitivity of nucleic acid detection cards was 10~(-6),10~(-5),10~(-4) and 10~(-7),respectively.The Ct values of N gene which were reached by high sensitivity antigen-detecting rapid diagnostic cards were as follows:original strain(10~(-4)) of more than 31,Beta variant(10~(-5)) of more than 36,Delta variant(10~(-4)) of more than 34,Omicron variant(10~(-5)) of more than 33,meeting the requirements of domestic and European Union for SARS-CoV-2 antigen-detecting rapid diagnostic cards.Conclusion All the antigen-detecting rapid diagnostic cards detected the four virus strains,while the sensitivity of different reagents to different variants varies to some extent,among which the sensitivity to Omicron variant varies the most.