Molecular epidemiology of measles viruses in China, 1995–2003

This report describes the genetic characterization of 297 wild-type measles viruses that were isolated in 24 provinces of China between 1995 and 2003. Phylogenetic analysis of the N gene sequences showed that all of the isolates belonged to genotype H1 except 3 isolates, which were genotype A. The nucleotide sequence and predicted amino acid homologies of the 294-genotype H1 strains were 94.7%–100% and 93.3%–100%, respectively. The genotype H1 isolates were divided into 2 clusters, which differed by approximately 2.9% at the nucleotide level. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Even though other measles genotypes have been detected in countries that border China, this report shows that genotype H1 is widely distributed throughout the country and that China has a single, endemic genotype. This important baseline data will help to monitor the progress of measles control in China

Comparison of Four Methods Using Throat Swabs To Confirm Rubella Virus Infection▿

Laboratory tests are essential for confirming sporadic cases and outbreaks of rubella. Detection of rubella virus is often necessary to confirm rubella cases and to identify specimens to be used to characterize wild-type rubella viruses. The sensitivities of four methods for detecting rubella virus infection using throat swabs, which had been collected in Henan and Anhui provinces in China, were evaluated. The methods used were reverse transcription (RT)-PCR followed by Southern hybridization using RNA extracted directly from clinical specimens, virus growth in tissue culture followed by virus detection by RT-PCR, low-background immunofluorescence in infected tissue culture cells using monoclonal antibodies to the structural proteins of rubella virus, and a replicon-based method of detecting infectious virus. Among these four methods, direct RT-PCR followed by hybridization was the most sensitive method; the replicon-based method was the least difficult to perform

Rubella Virus Genotypes in the People's Republic of China between 1979 and 2007: a Shift in Endemic Viruses during the 2001 Rubella Epidemic▿ †

The incidence of rubella cases in China from 1991 to 2007 was reviewed, and the nucleotide sequences from 123 rubella viruses collected during 1999 to 2007 and 4 viral sequences previously reported from 1979 to 1984 were phylogenetically analyzed. Rubella vaccination was not included in national immunization programs in China before 2007. Changes in endemic viruses were compared with incidences of rubella epidemics. The results showed that rubella epidemics occur approximately every 6 to 8 years (1993/1994, 2001, and 2007), and a shift of disease burden to susceptible young adults was observed. The Chinese rubella virus sequences were categorized into 5 of the 13 rubella virus genotypes, 1a, 1E, 1F, 2A, and 2B; cocirculations of these different genotypes were found in China. In Anhui province, a shift in the predominant genotype from 1F and 2B to 1E coincided with the 2001 rubella epidemic. This shift may have occurred throughout China during 2001 to 2007. This study investigated the genotype distribution of rubella viruses in China over a 28-year period to establish an important genetic baseline in China during its prevaccination era