Respiratory viruses, such as those that cause colds and influenza, are very common in the general population. The average adult will experience between 2 and 4 viral respiratory illnesses each year. It is known that respiratory viruses can cause flare-ups of chronic lung diseases such as asthma and chronic obstructive pulmonary disease. In children with CF, respiratory viral infections have been identified in nearly half of all exacerbations and are associated with a decline in lung function and increased frequency of hospital admission and acquisition of new bacterial pathogens.
Currently, little is known about the impact of viral infections on the course of CF lung disease in adults and no large-scale prospective studies in this area have been performed to date. It is unknown how often respiratory viruses can be found in patients with CF when they are well and what consequences they have on the course of exacerbations of CF lung disease. This study will identify the frequency of common viral infections in adults with CF and determine the effects they have on lung function, the rate and diversity of bacterial infection and patients' treatment burden. The information gained from this study will lead to improved prevention and treatment of respiratory infections in CF.