The Variants In H And F Genes In Wild-type Measles Virus Strain And Epidemiological Study In Changchun

Measles is an acute respiratory infection caused by the measles virus, children canbe seriously harmed. Measles in China was listed as one of the prevention andtreatment of infectious diseases in planned immunization, and can be listed as class Binfectious disease in the37kinds of infectious diseases. Viruses spread by dropletsleading to clinically symptom such as fever, upper respiratory tract inflammation, eyeconjunctivitis, red spot rash in skin, oral mucosa rash and remnants of pigmentation.Humans are the main hosts of measles virus; they can only infect certain apes andhumans.Five specimens of measles suspected cases were collected in2011. Afteridentifying them by Vero/SLAM, they had obvious CPE. Through RNA extractedfrom virus and then amplified by RT-PCR, they can be identified as measles virus.After sequence analysis about virus, we can screen evolutionary tree model by usingthe JModeltest. Software MEGA5.05was applied to analyze the genetic affinity ofcorresponding sequences between test results and international standard strainEdmonston strain, Shanghai-191and Changchun-47vaccine strains.The results showed that comparing with the China93-4，Five specimens ofmeasles on sequence homologies of H gene were99.0%～99.3%. Comparingwith the Edmonston stain，Five specimens of measles on sequence homologies of Hgene were94.8%～95.1%. The five-strain group genetic distance is less than0.004.Concerning with F gene，sequence homologies of F gene Comparing with theEdmonston stain，S191，changchun-47were98.9%~99.0%,98.9%～99.0%, and99.0%～99.2%，respectively. The five-strain group genetic distance is less than0.003.The results showed that the differences in5strains of wild-type measles virus ongene sequences were small. Comparing with previous wide strains which wereisolated before2010, there was no significant variation in the new separation of wild strains. wide strains had a lot of similarities with China93-4, the representative strainsof H1a subtypes, They, however, had lots of differences with standard strains ofEdmonston strain, S191,and Changchun47on the nucleotide and amino acid, whichprovided data for the for epidemiological analysis in future.