We conducted a systematic molecular epidemiological analysis of 146 imported cases between July 2021 and November 2022 in Zhejiang Province. Virus samples with cycle threshold (Ct) value less than 32 were performed next generation sequencing. Basing the whole genome sequence obtained after quality control and assembly of reads, the whole genome variation map and phylogenetic tree were constructed and further analyzed.
Our study identified critical months and populations for surveillance, profiled the variation of various lineages, determined the evolutionary relationships among various lineages of SARS-CoV-2, and compared the results in Zhejiang with those obtained worldwide during this period.
The continuous molecular epidemiological surveillance of imported cases of COVID-19 in Zhejiang Province during 2021 to 2022 is consistent with the global epidemic trend.
■我们对浙江省2021年7月至2022年11月的146例输入性病例进行了系统的分子流行病学分析。循环阈值(Ct)值小于32的病毒样品进行下一代测序。基于质量控制和读段组装后获得的全基因组序列,构建了全基因组变异图谱和系统发育树,并进行了进一步分析。
■我们的研究确定了监测的关键月份和人群,描绘了各种血统的变化,确定了SARS-CoV-2各个谱系之间的进化关系,并将浙江的结果与在此期间的全球结果进行了比较。
■浙江省2021-2022年COVID-19输入病例的连续分子流行病学监测与全球流行趋势一致。