Genetic characterization of wild-type measles viruses isolated in China, 2006-2007

Abstract

Molecular characterization of wild-type measles viruses in China during 1995-2004 demonstrated that genotype H1 was endemic and widely distributed throughout the country. H1-associated cases and outbreaks caused a resurgence of measles beginning in 2005. A total of 210,094 measles cases and 101 deaths were reported by National Notifiable Diseases Reporting System (NNDRS) and Chinese Measles Laboratory Network (LabNet) from 2006 to 2007, and the incidences of measles were 6.8/100,000 population and 7.2/100,000 population in 2006 and 2007, respectively. Five hundred and sixty-five wild-type measles viruses were isolated from 24 of 31 provinces in mainland China during 2006 and 2007, and all of the wild type virus isolates belonged to cluster 1 of genotype H1. These results indicated that H1-cluster 1 viruses were the predominant viruses circulating in China from 2006 to 2007. This study contributes to previous efforts to generate critical baseline data about circulating wild-type measles viruses in China that will allow molecular epidemiologic studies to help measure the progress made toward China's goal of measles elimination by 2012.

Measles incidence rate and a phylogenetic study of contemporary genotype H1 measles strains in China: is an improved measles vaccine needed?

“…This is consistent with recently published data from China [20]. In addition, we identified genetic variations in both the N and H genes of the wild-type MV isolates obtained from this outbreak and demonstrated diminished neutralizing antibody titers when post-vaccination sera were tested against the wild-type strains.…”

“…As a result, the incidence rate in Jilin Province rose to 17.41/ 100,000 in 2006 [26]. It has been proposed that increased migration (floating population) and decreased vaccination may be responsible for the recent upswing in measles cases throughout China [20]. The preponderance of measles cases in susceptible individuals in the present report would support this.…”

Molecular epidemiology of measles virus in Iran 2009–2010: First detection of measles genotype H1

“…Phylogenetic analyses conducted during the early part of the last decade identified two clusters (cluster 1 and 2) within the Chinese genotype H1 . Previously, importation of genotype H1 viruses into Taiwan, Hong Kong, and Europe, for which 100% sequence homology was shown with genotype H1 viruses which were circulating in mainland China [Ji et al, 2010]. This is in line with the present study in which phylogenetic analysis showed that the Iranian H1 strains were members of Cluster 1.…”

Emergence and Continuous Evolution of Genotype 1E Rubella Viruses in China

“…Measles and rubella are similar diseases, both characterized by a rash that may be difficult to differentiate clinically (35). In addition, rubella epidemics usually occur in the spring or early summer, similar to measles, peaking between April and May (13). Therefore, during the measles elimination campaign in China, particularly in 2009, when the incidence of rubella was higher than that of measles, measles control might have been hampered because large numbers of suspected measles cases, which were in reality rubella cases, may have appeared.…”