Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 12 5 2020 10 31 495 502 Mohammad Hadi Karbalaie Niya Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran AND Department of Medical Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Ali Salimi Jeda Department of Medical Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Ahmad Tavakoli Department of Medical Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran AND Pediatric Infectious Diseases Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran Hesam Sohani Department of Microbiology, Faculty of Biology, College of Sciences, University of Sciences and Research, Tehran, Iran Fahimeh Safarnezhad Tameshkel Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran Mahshid Panahi Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran Morteza Izadi Health Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran Farhad Zamani Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran Hossein Keyvani Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran AND Department of Medical Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran 2020 07 01 2020 10 31 Background and Objectives: Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection in many populations, including military recruits receiving basic training. Therefore, this study was set out to determine the molecular epidemiology, genotype and phylogenetic features of RSVs in patients with respiratory infection as a case study. Materials and Methods: In this study, military barracks of Tehran, Iran, between January to March 2017 exposed to respiratory diseases were used for sampling. Throat swabs were taken, a reverse transcriptase-polymerase chain reaction (RT-PCR) assay was performed to identify RSV and then the genotyping and phylogenetic analyses of RSVs in patients with a respiratory infection. Results: Among 400 Iranian military trainees with respiratory symptoms, RSV infection was identified in 2.75% (11/400) using RT-PCR. Sequencing showed the incidence of type A (2.5%, n=10) to be much higher than type B (0.25%, n=1); Sore throat was the most common symptom among RSV patients. Phylogenetic analysis revealed that the majority of strains from the studied samples were more consistent with those from the Philippines and the US strains. Conclusion: This study is the first to document RSV as a major cause of acute respiratory illness among military trainees in Iran. The prevalence of RSV is substantial in the cold season and the prevalence of genotype A is dominant in the country, leading to take essential steps in preparing a preventive vaccine against this viral infection. https://ijm.tums.ac.ir/index.php/ijm/article/view/2692 https://ijm.tums.ac.ir/index.php/ijm/article/download/2692/1286