Abstract
For many years viral causes of community-acquired pneumonia were often been given limited attention. The number of published studies on influenza alone increased fivefold from 2001 to 2010. Specifically several studies have underlined that the involvement of viruses in community-acquired pneumonia has been underestimated, and this underestimation has been attributed to a lack of appropriate diagnostic methods. Now, with the advent of modern molecular assays, it is well recognized that viruses account for the largest proportion of community-acquired pneumonia in preschool children in both developed and developing countries. Respiratory syncytial virus, influenza virus, adenovirus, and parainfluenza virus are the major pathogens involved, but the relative importance of additional viruses (rhinoviruses, bocavirus, human metapneumovirus) is increasing and will be better defined by future research.