Nationwide distribution of varicella-zoster virus clades in China

Abstract

BackgroundIn 2010, a universal nomenclature for varicella-zoster virus (VZV) clades was established, which is very useful in the monitoring of viral evolution, recombination, spread and genetic diversity. Currently, information about VZV clades has been disclosed worldwide, however, there are limited data regarding the characterization of circulating VZV clades in China, even where varicella remains widely epidemic.MethodsFrom 2008 to 2012, clinical samples with varicella or zoster were collected in General Hospital in eight provinces and analyzed by PCR, restriction endonuclease digestion and sequencing. The viral clades were determined by analysis of five single nucleotide polymorphisms (SNPs) within the 447-bp fragment of open reading frame (ORF) 22, and the restriction fragment length polymorphisms (RFLPs) of ORF 38 (PstI), ORF 54 (BglI) and ORF 62 (SmaI) were evaluated to understand genetic diversity of VZV and determinate varicella vaccine adverse event (VVAE).ResultsSeventy-seven varicella and 11 zoster samples were identified as being positive for VZV. The five SNPs profile showed that the majority of VZV strains belonged to clade 2, but clade 5 and clade 4 strains were also found in Guangdong. The RFLPs analysis of the DNA fragments of ORF 38, 54 and 62 showed that 85 of these samples were characterized as PstI + BglI + SamI-, and the remaining three VZV strains from varicella patients were characterized as PstI-BglI + SamI+ which is the genetic profile of VVAEs.ConclusionsThe study suggested that the predominant clade 2 VZVs had been continually circulating since at least the 1950s in China. Nearly all VZV strains except VVAEs possessed the genetic profile of PstI + BglI + Sam-. However, the other clades were also found to be co-circulating with clade 2, especially in the border regions. These results highlighted the need for the constant and broad use of virologic surveillance to provide an important genetic baseline for varicella control and vaccination programs in China.

Differentiation between wild-type and vaccines strains of varicella zoster virus (VZV) based on four single nucleotide polymorphisms

“…VZV strains have been classified into seven clades including two preliminary ones [6], in addition, clades VIII and IX were reported [12] (Table 3). Genotyping 15 of the 44 strains showed that samples from England were either clade 1 or 3, whilst the samples from China were clade 2 or in once case clade 4 (Table 1) confirming previous reports that clades 1 and 3 predominately circulate in Europe and the Americas, clade 2 is mainly found in Korea, Japan and China, and clades 4 and 5 are mainly detected in India, Nepal, Bangladesh and Africa [6–12, 27, 34]. To show that the technique could be used elsewhere for distinguishing between wt and vaccine VZV in various clades, especially clade 2 as vaccine Oka belongs to clade 2, it is important that this method was shown to work in representative clade 2 samples.…”

“…The 16 samples collected from Chinese patients comprised 11 chickenpox samples and five shingles samples. Nine of the samples had previously been genotyped [27] and belonged to clades 2 and 4 ( Table 1). The vaccination histories of Chinese patients were unknown, but routine varicella and shingles vaccination is not offered in China.…”

“…Due to the available volume of samples, 15 (eight from the UK and seven from China) specimens were further genotyped. Including the nine Chinese samples genotyped previously [27], there were six clade 1, 15 clade 2, two clade 3 and one clade 4 samples. All clade 1 and 3 samples were found in England and the clade 2 and 4 samples were found in China (Table 1).…”

An adult co-presented with varicella and herpes zoster caused by varicella zoster virus genotype J, China: a case report

“…The genotypic prevalence of VZV in China showed that VZV genotype J was the major prevalent strain from 2008 to 2012. In addition, VZV genotypes M1 and M2 also circulated in Guangdong [17]. VZV genotype J was also the dominant pathogen of VZV infection in Chinese children during August 2017-September 2017 in Suzhou, Jiangsu [18].…”

Characterization and Comparison of Genetic Variation in Clinical Varicella-Zoster Virus Isolates Collected from Shanghai and Urumqi, China

“…The varicella vaccine has been applied in China for more than 30 years, and the vaccine strains from VZV infected individuals are distributed epidemiologically (8).…”