Seroprevalence of measles antibodies by region, sex, and age group in the Jiangsu province, 2008–2010 (%).

<p>Abbreviations: CI, confidence interval. ^a CMH χ² test was used to test the trend in seroprevalence over years. The seroprevalence of the following stratifications showed a significantly increasing trend over years: north region, south region, male, female, ≤7 months old, and 8–12 months old. ^b Pearson's χ² test was used to detect differences between seroprevalence by region, sex, and age group in each year.</p

Region-specific geometric mean titers (GMTs) and prevalence of measles antibodies in different age groups from 2008–2010.

<p>The seroprevalence in each region showed an upward trend with age: the GMT climbed to a peak between 13 months - 4 years of age followed by a downward trend in subsequent ages (A, B, and C), similar to what was seen throughout the whole province (D). The seroprevalence in the central region declined dramatically in individuals 15–29 years old in 2010 (B).</p

Phylogenetic analysis of sequences of representative Chinese measles viruses, compared to the WHO reference sequences.

<p>These trees are based on the WHO standard sequence window within the N gene. Panel A. Phylogenetic tree of 87 representative measles isolates from China during 1993–2008 compared to the WHO reference sequences for each genotype. Sequences from Chinese viruses of H1a cluster from 1993–2008 are indicated by blue and sequences from Chinese viruses of H1b cluster from 1994–2005 are indicated by fluorescence green, and WHO reference strains are indicated by red. All isolates from China, including 3 WHO reference strains(Hunan.China93-7/H1, Beijing.China94-1/H2, MVi/Menglian.Yunnan.CHN/47.09/d11), are indicated by solid rounded dots. Panel B. Phylogenetic tree of 5 measles vaccine viruses from China compared to the A genotype strains of Edmonston wild type and other vaccine strains used worldwide. Sequences from viruses isolated in China are indicated by blue, and A genotype wild type Edmonston strain is indicated by red. Two Chinese measles vaccines are indicated by green solid triangles.</p

The geographical distribution of the genotypes and cluster of measles viruses isolated in China during three periods between 1993 and 2008.

<p>The provinces where the measles viruses of the indicated genotypes (clusters) were found are shown. The location within each province is not indicated. Genotype H2 viruses in Beijing may be classified as imports, and 5 genotype A viruses in four provinces are vaccine associated (see the text).</p

Number of measles cases and incidence from 1991 to 2008.

<p>Source: National Notifiable Diseases Reporting System (NNDRS). Blue bars indicate the reported measles cases and red solid diamonds indicate the incidence (/100,000 ) of each year. X-axis denotes year, left-hand y-axis denotes reported number of cases and right-hand y-axis denotes the incidence per 100,000.</p

Different epidemic trend of 2 clusters of H1 genotype viruses circulating in China during 1993–2008.

<p>The number on the top of each column represents the number of the isolates in each time period.</p

Primers used for amplification and sequencing of the entire H gene.

a<p>: s, sense orientation; as, antisense orientation.</p>b<p>: the primers' nucleotide locations and range on the basis of the Measles prototype strain: Edmonston complete genome (GenBank ID: AF266288).</p>c<p>: Length of the PCR product or use of the primer for sequencing (Seq).</p

Phylogenetic relationship based on the complete H gene sequences.

<p>Neighbour-joining tree was reconstructed with full-length H gene sequences from 56 genotype H1 wild-type measles isolates from mainland China, the WHO reference strains of each genotype and Chinese vaccine strains. The sequences of the circulating strains in 1993–1994 and in 2000–2009 are indicated by symbol “▴” and “•”, respectively, each color of symbol “•” represents the annually circulating strains. The genotype H2 reference strain below cluster 2 which is also marked by a triangle was identified in 1994, China. The branches for the different lineages are marked by various colors. The WHO standard name of MeVs and GenBank accession numbers of all the sequences are available in the figure. Numbers at nodes represent the percentage of 1,000 bootstrap replicates (values <70 are not shown). Bar, 0.005 nucleotide substitutions per site.</p

Reported measles cases and incidence in China, 1991–2009.

<p>The number above the column represents the number of representative measles strains selected for the complete H gene sequence analysis. Blue bars indicate the number of reported measles cases and yellow solid diamonds indicate the incidence (/100,000 population) of each year, the Arabic numerals above the x-axis indicates the number of deaths. X-axis denotes year, y-axis on left denotes reported number of cases and y-axis on right denotes the incidence per 100,000 population.</p

Alignment of the predicted amino acid sequences of the partial H gene.

<p>The variation of amino acid Ser240Asn (highlighted in blue) leads to the absence of a glycosylation site; the exchange of Pro397Leu (highlighted in pink) that results in loss of recognition of two monoclonal antibodies directed against HNE; the amino acid residues of putative binding sites for CD46, SLAM and seven cysteine residues were highlighted in red, yellow and purple, respectively.</p