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Objective: To analyze the genetic characterizations of wild type measles viruses caused the measles outbreak in Xinjiang., Methods: Vero/Slam cell were used for measles viruses isolation from the specimens collected from measles outbreaks patients. Fragment of 676 nucleotide acids of the carboxylend of nucleoprotein gene were amplified using reverse transcription-polymerase chain reaction (RT-PCR) method and then the PCR products were directly sequenced and analyzed. Phylogenetic tree was constructed based on 450 nucleotide acids of the N-terminus of nucleoprotein gene, and homological analysis was performed at nucleotide acid level., Results: 11 measles viruses were sequenced and all belonged to H1a subgenotype. The nucleotide difference was 0-0.2% between 11 Xinjiang isolates. And the nucleotide difference was 2.2%-2.4% between Xinjiang isolates and H1 genotype reference strain., Conclusion: The Measles viruses causing the measles outbreak in Xinjiang were H1a subgenotype.

Objective: To study genetic characteristic of fusion gene (F gene) of wild type measles virus circulated in 2006, analysis the variation regular of F gene through comparing with measles virus of 1999-2003., Method: 9 representative strains, which isolated from 8 provinces in 2006, were selected. The whole F gene were amplified by reverse transcript-polymerase chain reaction and were sequenced, then they were compared with the nucleotide acid sequences of Chinese measles vaccine strains and the representative strains of 1999-2003, finally the phylogenetic analysis were conducted., Results: Among 9 representative strains circulated in China in 2006, the homology of nucleotide acid and amino acid were 98.5%-99.8% and 99%-100% respectively, and they were 95.4%-96.2% and 96.7%-97.2% respectively compared with Chinese Vaccine strains, the homology of nucleotide acid and amino acid were 97.9%-99.7% and 98.1%-100% respectively compared with strains of 1999-2003, In F gene, the 3 glycosylation site (aa32, aa64 and aa70), aa112 and aa195, which played the important role to viral fusion, that have no changes., Conclusion: The F genes of measles virus of china in 2006 had no significant variation, the genetic diversity was not predominance comparing with strains of 1999-2003, and important functional sites in Fusion protein didn't change, the measles epidemic was not correlate with the F gene variation. Because F protein play an important role in Measles viruses, it needs to perform the routine monitoring of F gene, which benefit for understanding of epidemic features and genetic variation pattern of wild type Measles viruses.

Objective: To evaluate the running status of Measles laboratory network of China (Hong Kong, Macao and Taiwan were excluded) in 2008., Methods: To analyze the database of Measles laboratory network surveillance of the year 2008, and the database of serologic and virologic surveillance of National laboratory for Measles in Chinese Centers for Disease Control and Prevention(CCDC), then the indicators of the running of Measles laboratory network of China were analyzed., Results: 1, serologic surveillance: 107,160 Measles sera samples were collected between Feburary and September of 2008, and the collection rate was 77.93%; 53 778 samples were qualified and positive for IgM, the positive percentage was 50.2%. 2, Virologic surveillance: 287 Measles viral isolates were isolated by 18 provincial Measles laboratories in 2008, all were certified as H1a genotype, H1a genotype was still the predominant genotype circulating in China; 29 Rubella viral isolates were isolated by 4 provincial Measles laboratories in 2008, all belonged to 1E genotype. 3, Laboratory quality control: National laboratory for Measles passed the proficiency test and on-site review in 2008; all provincial Measles laboratories passed the sera samples recheck and proficiency test hold by National laboratory for Measles in 2008; Tianjin, Shanxi, Shandong, Zhejiang, Jilin, Hubei, provincial Measles laboratory passed the on-site review by WHO., Conclusion: The running status of Chinese Measles laboratory network was good in 2008, and good laboratory quality control system was also set up, methods such as specimens collection, serologic detection, cell culture and viral isolation, etc, were standardized, and applied to Chinese Measles laboratory network, and it provided important scientific basis for eradication Measles in the year of 2012.

Objective: To study the genotype and gene characterization of measles wild viruses circulated in Jilin provinces, and to provide scientific evidences for setting down controlling and preventing strategy and measures., Methods: 38 strains of measles virus isolated in 2001-2006 were genotyped by RT-PCR-RFLP, some strains of measles virus in Jilin province were chosen for the phylogenetic analysis and for the homology analysis of nucleotide and amino acid sequences., Results: All the 38 strains of measles virus were identified as H1 genotype by RT-PCR-RFLP, and 29 strains of them were identified further as H1 a by sequence analysis. The homology of nucleotide was 88.0%-89.4% and the homology of amino acid was 91.8%-92.7% .The average diversity was less than 1.4%., Conclusion: The measles virus of H1a genotype was the circulating virus within recent years in Jilin province. There were the same measles virus strains circulating and transmitting at different years and also the different H1a measles virus strains co-circulating at the same year. There were the same transmission chain caused by the same measles virus with other provinces.

Objective: A new simple RT-LAMP method was applied to detect measles virus nucleic acid and compared with nest-RT-PCR., Methods: Compare the detection rate of the RT-LAMP method with that of nest-RT-PCR by detecting measles virus nucleic acid from measles virus and clinical samples., Results: The nucleic acid positive rates of all 23 strains of measles virus are all 100% by the two methods. But to the detection of 18 clinical samples which are negative in measles isolation, the nest-RT-LAMP showed 56.52% positive rate of nucleic acid of measles virus and nest-RT-PCR showed 47.83%., Conclusion: RT-LAMP is more sensitive than nest-RT-PCR.