Identification of SARS-CoV-2 through combined 2nd and 3rd generation sequencing technology / 中国人兽共患病学报

To rapidly and accurately identify novel SARS-CoV-2 variants,we used combined 2nd and 3rd generation sequen-cing technology to sequence and analyze the viral genomes of two specimens from SARS-CoV-2 infection cases imported into Fujian Province.Nanopore and Illumina techniques were used to perform whole genome sequencing of SARS-CoV-2.A pangolin system was used to determine the virus type.Evolutionary analysis software was used to construct the phylogenetic tree.Next-clade was used to analyze the whole genome variation,and estimate ACE2 receptor affinity and immune escape ability.Two complete genome sequences of SARS-CoV-2 were obtained from respiratory specimens from the two cases,with lengths of 29 665 bp and 29 682 bp.The average genome coverage were＞99.0％,and the virus typing results all indicated Omicron BQ.1 lineage.Phylogenetic analysis demonstrated that the two viruses were located in the same cluster of the Omicron BQ.1 line-age.On the basis of these findings and epidemiological data,we speculated that the two cases might have originated from the same infection.Variation analysis indicated that the two viruses shared all 77 mutation sites;except for S:A27S and S:24-26del,all were characteristic mutation sites of the BQ.1 lineage.The predicted ACE2 receptor affinity and immune escape abili-ty scores of the two viruses were both＞0.6,thus suggesting significant changes in their biological characteristics and requiring continuous monitoring and warning.The combined 2nd and 3rd generation sequencing technology was successfully applied to i-dentify the first BQ.1 lineage of the SARS-CoV-2 imported into Fujian Province,considering the timeliness and accuracy of whole genome sequencing,thus providing a technical reference for SARS-CoV-2 variant monitoring.

Laboratory investigation of a clustered respiratory tract infection with human adenovirus / 中国人兽共患病学报

In order to investigate the pathogens associated with a clustered event of fever occurred in a kindergarten in Fuzhou,Fujian Province,samples were collected from pediatric cases in the kindergarten and screened for various possible viral agents by real-time PCR.Of 10 respiratory specimens,7 were positive of human adenovirus (HAdV).The positive samples were inoculated into HEp-2 cell-lines for viral isolation.The PCR products of the hypervariable regions of Hexon gene were sequenced,followed by BLAST searches for viral type identification.In comparison with the strains prevalent in domestic or abroad in recent years,the deduced amino acid sequences showed no amino acid mutation in the hypervariable regions of Hexon.Combined with clinical manifestation and field epidemiological data,human adenovirus type 7 could be confirmed as the pathogen linked to the clustered event.