Objective To understand and evaluate the overall status of nucleic acid detection efficacy for influenza A virus in the na-tionwide clinical laboratories of China,and discover and identify the potential issues to further improve the detection quality.Methods During 2024,the National Center for Clinical Laboratories distributed five samples to nationwide 1 367 participating laboratories.The detection efficacy of each participating laboratory was evaluated by calculating the overall percent agreement(OPA)of the test results using different detection reagents.Results The results of OPA,positive percent agreement(PPA)and negative percent agreement(NPA)of the five samples were 99.87％(6 826/6 835),99.89％(5 462/5 468),and 99.78％(1 364/1 367),respectively.No statistical difference of PPAs was observed between the H3N2 samples with different concentrations,between H1N1(2009)and H3N2 samples with equivalent concentration(1.0×104 copies/mL),and between seasonal H1N1 and H3N2 samples with equivalent concen-tration(1.0×105 copies/mL)(P＞0.05).Conclusion The results indicated the clinical laboratories in China exhibited robust efficacy in the molecular detection for two prevalent influenza A virus subtypes,i.e.,H1N1(2009)and H3N2.However,false-negative and false-positive results were encountered in a few laboratories.

Objective To understand and evaluate the overall status of nucleic acid detection efficacy for influenza A virus in the na-tionwide clinical laboratories of China,and discover and identify the potential issues to further improve the detection quality.Methods During 2024,the National Center for Clinical Laboratories distributed five samples to nationwide 1 367 participating laboratories.The detection efficacy of each participating laboratory was evaluated by calculating the overall percent agreement(OPA)of the test results using different detection reagents.Results The results of OPA,positive percent agreement(PPA)and negative percent agreement(NPA)of the five samples were 99.87％(6 826/6 835),99.89％(5 462/5 468),and 99.78％(1 364/1 367),respectively.No statistical difference of PPAs was observed between the H3N2 samples with different concentrations,between H1N1(2009)and H3N2 samples with equivalent concentration(1.0×104 copies/mL),and between seasonal H1N1 and H3N2 samples with equivalent concen-tration(1.0×105 copies/mL)(P＞0.05).Conclusion The results indicated the clinical laboratories in China exhibited robust efficacy in the molecular detection for two prevalent influenza A virus subtypes,i.e.,H1N1(2009)and H3N2.However,false-negative and false-positive results were encountered in a few laboratories.