Contribution of viruses, Chlamydia spp. and Mycoplasma pneumoniae to acute respiratory infections in Iranian children.

The study reports the frequency and clinical presentation of respiratory syncytial virus (RSV), human metapneumovirus, influenza (Inf V), parainfluenza, adenovirus (Adv), Chlamydia spp. and Mycoplasma pneumoniae in children with acute respiratory infections (ARI) in Rasht, Iran. Nasopharyngeal aspirates and swabs were collected from 261 children in 2003 and 2004. Pathogens were detected using polymerase chain reaction (PCR) and reverse transcription-PCR (RT-PCR), confirmed with sequence analysis. Ninety-three pathogens were detected in 83 children. RSV was present in 39 (15%), Adv in 37 (14%), Inf A in 11 (4%), C. trachomatis in 4 (2%) and M. pneumoniae, in 2 (1%) children. Neither parainfluenza nor metapneumovirus were detected. RSV, Inf A and C. trachomatis were more frequent in children with lower respiratory infections. Adv presented more frequently as upper respiratory infection. All pathogens, except M. pneumoniae, were detected in children with severe pneumonia. Viruses play a significant role in Iranian children with community-acquired ARI.