Viral infections in children with community-acquired pneumonia.

Viral pathogens are commonly isolated from children with community-acquired pneumonia (CAP). Viruses like respiratory syncytial virus, human rhinovirus, human metapneumovirus, parainfluenza viruses, and influenza may act as sole pathogens or may predispose to bacterial pneumonia by a variety of mechanisms. New, emerging, or reemerging viral pathogens occasionally cause outbreaks of severe respiratory tract infection in children. The 2009-2010 H1N1 influenza virus pandemic resulted in increased rates of influenza-related hospitalizations and deaths in children. Rapid viral diagnostic tests based on antigen detection or nucleic acid amplification are increasingly available for clinical use and confirm the importance of viral infection in children hospitalized with CAP. Recently published guidelines for the management of CAP in children note that positive viral test results can modify clinical decision making in children with suspected pneumonia by allowing antibacterial therapy to be withheld in the absence of clinical, laboratory, or radiographic findings that suggest bacterial coinfection.