To the Editors:
Recent epidemics of virulent respiratory viruses, such as H1N1 influenza and severe acute respiratory syndrome coronavirus (SARS-CoV), have highlighted the clinical importance of methods for the rapid and accurate detection of respiratory virus infection [1, 2]. A diagnosis of a respiratory viral infection may have implications for infection control measures and treatment of patients [3]. Molecular-based techniques offer a more rapid and sensitive method for diagnosis of respiratory viral infection than viral culture or serology [4]. PCR-based methods can be applied to nasal and/or throat swab samples for the rapid detection of common respiratory viruses [5]. As the majority of adults with cystic fibrosis (CF) produce sputum during infective exacerbations, we investigated whether sputum is a suitable medium for the diagnosis of respiratory viral infections in patients with CF using a PCR method, by comparing results …