Genetic variability of respiratory syncytial virus A in hospitalized children in the last five consecutive winter seasons in Central Spain.

Human respiratory syncytial virus group A (RSV-A) was detected in symptomatic hospital attended children in Central Spain for a continuous time period, September 2010 to April 2015. In order to accurately describe the epidemiology of this virus, the genetic diversity of the complete G gene and the clinical manifestations observed were jointly analyzed. Out of 3,011 respiratory specimens taken from 2,308 children, 640 were positive to RSV (21.3%) and 405 were RSV-A (63.2%). Complete G gene sequences of 166 randomly selected RSV-A virus identified NA1 and ON1 genotypes. In 2011-2012, ON1 emerged sporadically and become dominant in 2012-2013 with 38 cases (70%). In 2014-2015, all the 44 sequences contained the 72-nt duplication (100%). Clinical diagnosis of children with ON1 genotype were bronchiolitis in 55 (62.5%), recurrent wheezing or asthma exacerbations in 22 (25%), laryngotracheobronchitis in 3 (3.4%), and upper respiratory tract infections in eight. Results showed replacement and substitution of circulating NA1 genotype with the new ON1 genotype. Nevertheless, at this stage, none of the RSV-A genotypes identified have resulted in significant clinical differences. The amino acid composition of the complete G gene ON1 sequences demonstrated an accumulation of single changes not related with different clinical presentation. J. Med. Virol. 89:767-774, 2017. © 2016 Wiley Periodicals, Inc.

Calderón A ，Pozo F ，Calvo C ，García-García M ，González-Esguevillas M ，Molinero M ，Casas I ... -  《-》

Molecular epidemiology of respiratory syncytial virus for 28 consecutive seasons (1990-2018) and genetic variability of the duplication region in the G gene of genotypes ON1 and BA in South Korea.

Yun KW ，Choi EH ，Lee HJ 《-》

Respiratory syncytial virus subtype ON1/NA1/BA9 predominates in hospitalized children with lower respiratory tract infections.

Respiratory syncytial virus (RSV) infection is the leading cause of acute respiratory tract disease in children less than 5 years old. The aim of this study was to further elucidate the molecular properties and clinical characteristics of RSV infection. The study sample included 238 patients <5 years old who were hospitalized with clinical symptoms of upper or lower respiratory tract infection (URTI or LRTI) in the Pediatric Department at the First People's Hospital of Chenzhou, South China in 2014. We subjected nasopharyngeal aspirate (NPA) or nasal swab (NS) samples from the patients to indirect fluorescence assay screens. RSV G genes were amplified by reverse transcription-PCR (RT-PCR) and sequenced. Of the 238 patients screened, 64 (26.8%) were confirmed to have RSV infections. Of those 64 confirmed RSV infection cases, 39 (60.9%) had subtype BA9, 13 (20.3%) had the recently identified subtype ON1, 11 (17.2%) had subtype NA1, and 1 (1.6%) had subtype GB2. The predominant presentation was LRTI with coughing, sputum production, fever, and wheezing. RSV subtype NA1 and BA9 infections were found mostly in infants, whereas the age distribution of subtype ON1 infections was more uniform across the age bands. Phylogenetic analysis indicated that, compared with the prototype strain A2, all ON1 and most NA1 isolates had lost one potential N-glycosylation site at amino acid 251 and 249 due to T251K and N249Y substitution, respectively. These findings suggest that NA1, BA9, and ON1 are the dominant RSV subtypes causing respiratory tract infections in young children presenting to the hospital in South China. J. Med. Virol. 89:213-221, 2017. © 2016 Wiley Periodicals, Inc.

Fan R ，Fan C ，Zhang J ，Wen B ，Lei Y ，Liu C ，Chen L ，Liu W ，Wang C ，Qu X ... -  《-》

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

Human respiratory syncytial virus (HRSV) is a major pathogen that causes worldwide seasonal epidemic disease in infants due to its genetic variations. However, published information on the molecular epidemiology of HRSV was never reported particularly in Chengdu of West China. During five consecutive seasons (from 2009 to 2014), 433 (23.7%) of 1827 samples from hospitalized patients were identified as HRSV positive. Epidemiological characteristics of HRSV revealed that subtype A viruses (62.7%) prevailed in the first three epidemic seasons and faded in the next two seasons, while subtype B viruses (37.3%) kept circulating in five epidemic periods. According to the phylogenetic analysis of glycoprotein (G) gene, five HRSV genotypes NA1, ON1, BA9, BA-C, and CB1 were found in Chengdu. The predominant circulating genotype changed from NA1 in the period of 2010-2012 to BA9 of 2013-2014. The newly emerging ON1 was first reported in West China in October 2013. The early genotypes BA-C and CB1 were replaced by the prevailing BA9 after the third epidemic peak. Genetic mutations in glycosylation sites of G protein were found in HRSV variants, suggesting the virus is able to escape the immune recognition and attack. This study elucidated the local HRSV epidemic was associated with the alternate circulation of multiple genotypes and with the change of glycosylation sites of G protein. J. Med. Virol. 89:32-40, 2017. © 2016 Wiley Periodicals, Inc.

Hu P ，Zheng T ，Chen J ，Zhou T ，Chen Y ，Xu X ，Pei X ... -  《-》

[Molecular biological and clinical characteristics of respiratory syncytial virus in children with bronchiolitis].

Zhang TH ，Deng J ，Qian Y ，Zhu RN ，Sun Y ，Wang F ，Tian R ，Zhao LQ ... -  《-》