Molecular characterization of human respiratory syncytial virus subtype B: A novel genotype of subtype B circulating in China

Abstract

Human respiratory syncytial virus (HRSV) is major pathogen of lower respiratory tract infections in infants and young children worldwide. There have been many studies regarding HRSV subgroup A (HRSV-A) G protein genetic variability but little information about HRSV subtype B (HRSV-B) G protein genetic diversity and molecular evolution in China. Thus, a survey of the molecular epidemiology and evolution of the G protein in China is of high importance. In this study, the circulation and genetic diversity of HRSV in Chongqing, Southwestern China, from June 2009 to May 2013, were investigated. A total of 3,167 nasopharyngeal aspirates were obtained in this study, and it was found that HRSV-B predominated in the 2009-2010 and 2012-2013 epidemic seasons. This study identified the genetic variability of the glycoprotein G gene among 102 HRSV-B strains isolated by cell culture from Chongqing nasopharyngeal aspirates, and 68 Chinese HRSV-B sequences were deposited in GenBank. Genotyping and phylogenetic analysis revealed that the HRSV-B strains were clustered into three genotypes: BA (n = 111, 65.29%), GB3 (n = 5, 2.94%), and a new GB genotype (n = 54, 31.77%) named GB5. The GB5 strains varied from other genotypes in the central conserved region and N-glycosylation sites. The estimated evolutionary rate of Chinese HRSV-B was 2.01 × 10(-3) nucleotide substitutions/site/year, which is similar to the reports from Belgium and the Netherlands with 1.95 × 10(-3) and 2.78 × 10(-3) nucleotide substitutions/site/year, respectively. This study provides data on the circulating pattern and molecular characterization of HRSV-B genotypes in China during four consecutive years and may contribute to HRSV vaccine development.

Alternate circulation and genetic variation of human respiratory syncytial virus genotypes in Chengdu, West China, 2009‐2014

“…The study recognized the genotypes of HRSV strains using the phylogenetic analysis of HVR2 nucleotide sequences of G gene. Previous studies recorded the emergence of new HRSV genotypes and the circulation of its multiple genotypes [Venter et al, ; Trento et al, ; Dapat et al, ; Arnott et al, ; Eshaghi et al, ; Cui et al, ; Ren et al, ]. Our findings showing GA2 and BA9 identified as the prevailing genotypes were consistent with the early findings in Beijing [Cui et al, ] and Shanghai [Liu et al, ].…”

“…Usually, the HRSV positive rate is higher in the hospitalized cases than in the outpatients. Consistently, the hospitalized children from Chongqing (32.7%) [Ren et al, ], Chengdu (23.7%), Beijing (15.8%) [Cui et al, ], and Shenzhen (14.6%) [He et al, ] had the higher HRSV positive rates than the outpatients from Shanghai (7.6%) [Liu et al, ]. Of all the possible reasons for the higher HRSV positive rates in Western China (Chongqing and Chengdu), one might be the local high humidity which can help to protect virus from desiccation, ultraviolet and loss of infectivity [Welliver, ].…”

Emergence of ON1 genotype of human respiratory syncytial virus subgroup A in China between 2011 and 2015

“…Interestingly, a similar sequence insertion was discovered in the HRSVB subgroup years before the discovery of the ON1 genotype: genotype BA with a 20-amino acid insertion in the HVR2 region of the G protein. More importantly, the BA genotype has circulated all over the world and evolved into 12 subgenotypes since its emergence in 1999 16, 34 . The spread of the BA genotype globally during the past decade suggested that the sequence repeat may provide some advantage to the virus 35 .…”

“…According to the genetic characteristic and reactivity with monoclonal antibodies, HRSV is classified into 2 subgroups, A (HRSVA) and B (HRSVB) 11 . To date, there are 15 genotypes of HRSVA (GA1-GA7, SAA1, CB-A, NA1-4 and ON1-2) 12–15 , and 24 genotypes of HRSVB (GB1-GB4, SAB1-SAB4, URU1-2, BA1-12, GB5/CB1 and CBB) 16–20 . The HRSVA genotype ON1 was first detected with a 72-nucleotide duplication in the HVR2 region encoded by the G gene in Canada in 2010.…”

Epidemiological characteristics and phylogenic analysis of human respiratory syncytial virus in patients with respiratory infections during 2011–2016 in southern China

“…Although RSV has only one single serotype, it can be divided into two antigenic groups -RSV-A and RSV-Baccording to the antigenicity of the G protein (Mufson et al, 1985). To date, 14 genotypes of RSV-A and 25 genotypes of RSV-B have been confirmed (Ren et al, 2015;Shobugawa et al, 2009), suggesting that genetic variability and evolution of RSV exists. However, data concerning the molecular epidemiological characteristics of RSV subtypes are limited, and there are few reports about the epidemiological status and genotypic characteristics of RSV prevailing in patients with acute respiratory infections (ARI) in southern China (Liu et al, 2016).…”