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Abstract@#A large rubella epidemic is currently ongoing since 2018 in Osaka, Japan. The detected rubella viruses were classified into genotypes 1E lineage 2 and 2B lineage 1. These strains may have been imported from endemic countries, and these viruses spread within the susceptible population.
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Objective@#To analyze the molecular epidemiological characteristics of rubella virus wild strains isolated in Shanghai during 2011-2017.@*Methods@#Throat swabs were collected from suspected measles or rubella patients in Shanghai during 2011-2017, which were identified as rubella and excluded measles by laboratory tests. Throat swabs were used to conduct cell culture for rubella virus isolation. After identification by RT-PCR, the nucleic acid of gene E1 of rubella virus was amplified and sequenced, followed by molecular epidemiological analysis.@*Results@#Totally 395 strains of rubella virus were isolated from 684 throat swabs. Compared 377 isolates with the WHO reference strains of all genotypes, phylogenetic tree was constructed based on the amplified 739 nucleotides sequences. These isolates were characterized as two genotypes respectively, 109 strains were defined as genotype 1E which were closer to the WHO reference strain from China (RVi/Shandong.CHN/0.02/), and others were genotype 2B while 5 strains of them were defined as a lineage. Most of the nucleotide mutations were nonsense mutation, and the amino acid sequences were highly conserved. All the genotype 1E rubella viruses except one strain had the same mutation at aa338 site.@*Conclusions@#Two genotypes of rubella virus circulated in Shanghai during 2011-2017.Genotype 1E appeared to be the predominant genotype during 2011-2013, genotype 2B was continuously existing since being found in 2011 and appeared to be the predominant genotype during 2014-2016.
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Objective To identify the rubella virus circulated in Guizhou province in 2012 ,and confirm the genotype and analyze the genetic characterization of rubella virus isolated .Methods The throat swab samples were collected from suspected rubella cases during the rubella outbreak and sporadic in 2012 .Rubella virus isolation was performed using Vero/SLAM cells .The presence of vi-ral RNA was detected using real-time RT-PCR after RNA extraction from infected tissue culture cells .Fragments of 944 nucleotides of E1 genes of the isolates were amplified by RT-PCR ,the PCR products were directly sequenced and analyzed .The phylogenetic trees based on the 739 nucleotide sequences 1E was conducted with the rubella viruses isolated in Guizhou province in 2012 and 32 WHO reference sequences representing 13 genotypes .Results 5 rubella virus strains were isolated in Guizhou province for the first time .The results of phylogenetic analysis showed that all 5 rubella virus isolates belong to genotype 1E .The nucleotide acid and a-mino acid homology among 5 rubella virus isolates were 99 .8% -100 .0% and 100 .0% respectively .Compared with the WHO ref-erence strain (Chinese strain T14-CH-02) ,the nucleotide acid and amino acid homology were 98 .7% -98 .9% and 100 .0% respec-tively ;while compared with another WHO reference strain (Malaysia strains M1-MAL-01) ,the nucleotide acid and amino acid ho-mology were 97 .5% -97 .6% and 99 .5% .Conclusion Genotype 1E rubella virus was the predominant genotype in Guizhou prov-ince in 2012 ,which was similar to the other provinces .This study accumulated the molecular epidemiological baseline date in Guizhou province .