1WHO. Nomenclature for describing the genetic characteristics of wildtype measles viruses (Update). Weekly Epidemiologieal Record,2001, 76:241-247.
2WHO. Nomenclature for describing the genetic characteristics of wildtype measles viruses ( Update ) . Part Ⅱ . Weekly Epidemiological Record, 2001,76:249-256.
3Rota PA. RNA extraction and reverse transcription -polymemse chain reaction (RT-PCR). Standard protocols for molecular epidemiology measles section, CDC, 2002. Available from :http://www. cdc. gov/.
4Xu W , Tamin A, Rota JS, et al. New genetic group of measles viruses isolated in the People's Republic of China. Virus Res, 1998,54 : 147-156.
5Katayama Y, Shibabara K, Kohama T, et al. Molecular epidemiology and changing distribution of genotypes of measles virus fields strains in Japan. J Clin Microbiol,1997 ,35 :2651-2653.
