Objective: To ascertain the genetic characterization and genotype of measles viruses isolated in Shanghai region, in 2005.
Methods: Measles virus was isolated from throat swab specimens collected from suspected measles cases and 450 bp fragment of C terminus of nucleprotein (N) gene was amplified by RT-PCR. Sequence analysis was conducted to ascertain the genotype and to compare the difference of nucleotide with other measles virus strain published in GenBank.
Results: 4 measles viruses were isolated from 10 throat swab specimens, and the sequence analysis indicated that they belonged to H1 genotype. The homogeneity of 450 nucleotides in the C terminal of the N gene was at 98%-98.2% as compared to H1 genotype (China93-7). They differed from genotype H2 (China94-1) at 6.4%-6.9% and from genotype A (Edmonston) at 6.7%-6.9%, from measles vaccine (Shanghail91) at 7.6%-8.0%. They differed from the other measles viral strain isolated in China in 1993 - 2005 at 0.2%-3.7%. The variation within 4 isolated measles viruses was at 0.7%-1.3%.
Conclusion: It was H1 genotype measles viruses,which are the native viruses in China that led to the outbreak of measles in Shanghai, in 2005.