Prevalence of human respiratory syncytial virus circulating in Iran

Respiratory syncytial virus [RSV] is a leading cause of acute respiratory infection during early childhood and is associated with a great burden on patients, parents, and society. While no treatment is yet available, results from recent phase 2 clinical trials of cell-entry inhibitors and RSV vaccines are promising. To prepare for introduction of these novel therapeutics, good understanding of its molecular epidemiology and continuous RSV surveillance data are necessary. This paper provides an overview of RSV prevalence and genotype distribution in Iran from 1996 to 2013. This meta-analysis includes 21 published studies. In total, 775 [18.7%] of 4140 respiratory specimens were positive for RSV infection. The male-female ratio of RSV-positive patients was 1.5:1. Significant peaks of RSV infection were detected during the cold season [November-March]. RSV infection was mainly observed in patients <2 years of age. Phylogenetic studies showed that genotypes GA1, GA2, GA5, and BA co-circulated in Iran in 2007-2013. This review highlights the necessity of introducing standard molecular surveillance programs to inform the epidemiological, clinical, and pathological characteristics of various RSV genotypes. Improved understanding of the molecular epidemiology will be useful for development of novel RSV therapeutics

Genetic diversity in the G protein gene of human respiratory syncytial virus among Iranian children with acute respiratory symptoms

Acute respiratory infection [ARI] is the major cause of morbidity and mortality in children worldwide. Human respiratory syncytial virus [HRSV] is main viral agent of ARI in infants and young children in terms of effect and prevalence. The aim of this study was to investigate HRSV genotypes during one season in Iran. In this cross-sectional study, 107 throat swabs were collected from children less than 5 years of age with acute respiratory infection from October to December 2009. The respiratory samples were obtained from several provinces: Tehran, Isfahan, Hamadan, Zanjan, Kordestan, Lorestan and West Azarbayjan, and were tested for G protein gene of HRSV by RT-PCR. Of the 107 respiratory samples, 24 [22.42%] were positive for HRSV, of which 16 [66.6%] belonged to subgroup A and 8 [33.4%] to subgroup B. Phylogenetic analysis revealed that subgroup A strains fell in two genotypes GA1 and GA2, whereas subgroup B strains clustered in genotype BA. This study revealed that multiple genotypes of HRSV cocirculated during the season 2009 in Iran. Also subgroup A strains were more prevalent than subgroup B strains, and genotype GA1 was predominant during the season