The occurrence of polyomaviruses WUPyV and KIPyV among patients with severe respiratory infections.

In 2007, the new polyomaviruses WUPyV and KIPyV were identified in patients with acute respiratory infections. The aim of this study was to investigate these viruses in hospitalized patients with severe acute respiratory infection (SARI). A retrospective study was conducted with 251 patients, from April 2009 to November 2010, using nasopharyngeal aspirates, naso- and oropharyngeal swab samples from hospitalized patients (children < 12 years and adults) who had SARI within 7 days of the onset of symptoms, including fever (> 38.8 °C), dyspnea, and cough. Clinical and epidemiological information was obtained through standardized questionnaire. Enrolled patients were initially suspected to have influenza A(H1N1)pdm09 infections. WUPyV and KIPyV were detected by real-time PCR. Samples were also tested for influenza A and B viruses, human respiratory syncytial virus, rhinovirus, metapneumovirus, coronavirus, adenovirus, and parainfluenza viruses. WUPyV and KIPyV were detected in 6.77% (4.78% and 1.99%, respectively) of hospitalized patients with SARI. All samples from children showed coinfections (rhinovirus was the most commonly detected). Six adults had polyomavirus infection and four (1.6%) had monoinfection. Of them, 3 reported comorbidities including immunosuppression and 1 patient had worse outcome, requiring ICU admission. These preliminary data may suggest a possible role of polyomaviruses in SARI among immunocompromised adult patients.