Validation of multiplex PCR assays
All the 24 positive samples confirmed the test reproducibility of the assays; four of them excluding the one used before for multiplex assays were taken as representative to display the reproducibility in this article (Fig.2 IIIA-IIIC ). In this study, only GR clade was found in all positive samples tested. The homology of the nucleotide sequences for the PCR products showed more than 99% identity with the respective positions of the clades that validated the assays (supplementary Fig.s2 ). Accession IDs to the submitted sequences for one positive sample as an archetype are available in GISAID EpiFlu™ database (EPI_ISL_548260, EPI_ISL_561630, EPI_ISL_561375, EPI_ISL_561376 and EPI_ISL_561377).