ABSTRACT
Human respiratory system is harbored by a vast array of transient and normal microbial flora. A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respiratory tract. Molecular methods were developed for detection of these viruses during last two decades. Nucleic acid amplification methods were introduced for rapid and accurate diagnosis of pathogenic viruses. Multiplex detection systems were employed to identify a panel of pathogenic viruses, which requires specialized kits and instruments in some cases. This review summarizes different types of molecular approaches which were developed with time and applied for the detection of pathogenic viruses associated with infections of the respiratory system.