Their report, published in this week's issue of the Proceedings of the National Academy of Sciences, underlines how little doctors know about the sources of most respiratory infections.
In their sample of 540 children in a pediatric hospital ward, the new bocavirus was responsible for 17 of the cases, the Swedish researchers found.
"Lower respiratory tract infection is a leading cause for hospitalization of infants and young children and accounts for 250,000 hospitalizations a year in the United States alone," Tobias Allander of the Karolinska Institute in Stockholm and colleagues wrote in their report.
