During the study period, 1,326 NPA of hospitalized children with febrile respiratory tract diseases were received for viral diagnostic evaluation. The median age of the patients was 1.6 years (mean age 3.2 years; range 7 days-22 years), and 58.4% were boys. DNA of 1,277 NPA from 1,085 children was available for retrospective testing. Of these, 62 (4.9%) samples from 59 children were positive by WUPyV PCR and subsequent sequencing. The median age of the WUPyVpositive children was 3.0 years (mean 2.9 years; range 4 months-6.3 years) ( Figure) , and 57% were boys. Of the children with WUPyV-positive NPA, 3.2% were >6 years of age, although children in this age group constituted 15.7% of the total population. Infections with WUPyV were found year round, but most occurred in the winter months. Yearly frequencies (July-June) of WUPyV-positive results varied from 3.2% to 8.5% during the observation period. These variations were not statistically signifi cant. In 34 (54.8%) of the WUPyV-positive samples, co-infections with other respiratory viruses were detected, most frequently with adenovirus (n = 10) and fl uA (n = 10), followed by hBoV (n = 9) and RSV (n = 5). The co-infections bronchitis, wheezing bronchitis, and pneumonia.