WU Polyomavirus Infection in Children, Germany

To the Editor: The human polyomaviruses JC and BK are known to cause persisting infections, which are usually asymptomatic in immunocompetent patients but may lead to severe disease in those who are immunosuppressed (1).Recently, 2 novel viruses of the family Polyomaviridae were detected in respiratory samples and named KI (2) and WU polyomavirus (WUPyV) (3).To investigate the frequency of WUPyV infections in Germany, we examined nasopharyngeal samples from hospitalized children with acute respiratory diseases for WUPyV DNA.The samples tested for WUPyV infection consisted of stored nasopharyngeal aspirates (NPA) of hospitalized children at the Children's Hospital, University of Würzburg.The samples had been received for routine screening of respiratory viruses from January 2002 through September 2005 and from January 2007 through July 2007.All samples were routinely tested for antigens of adenoviruses, infl uenza viruses A (fl uA) and B, parainfl uenza viruses 1-3, and respiratory syncytial virus (RSV) by indirect immunofl uorescence assays (Chemicon, Temecula, CA, USA).Remaining NPA material was stored at -20°C.DNA was extracted from the samples by using the High Pure Viral Nucleic Acid Kit (Roche, Mannheim, Germany) and stored at -70°C for further testing.All samples were also tested for human bocavirus (hBoV) DNA by PCR (4).WUPyV PCR was performed by using the primer pair AG0048 and AG0049 described by Gaynor et al.(3).PCRs were conducted in a 50-μL volume consisting of 5-μL extracted DNA, 1× Qiagen HotStar buffer (QIAGEN, Hilden, Germany), dNTPs at fi nal concentrations of 200 μmol/L each, 200 pmol of each primer, and 1.5