A simple sugar used in inhalers could prevent the onset of bacterial infections in cystic fibrosis (CF) sufferers. Bacterial infections in CF sufferers occur because the level of salt concentration in the surface airway liquid is too high, preventing the production of an effective immune response to the invading bacteria. In a study published in the 10 October issue of PNAS, a team from the University of Iowa, USA, found that a sugar called xylitol could be used to lower the salt concentration in the airways. Xylitol is not used by airway bacteria, so it could enhance the ability of the immune system to kill bacteria without promoting bacterial growth. A nasal spray containing the sugar was tested on a dozen volunteers and it significantly reduced the number of nasal bacteria detected. Dr Michael Walsh commented: "The hope is that this could help prevent, or at least delay, the onset of infection in lungs of people with cystic fibrosis, and people who don't have cystic fibrosis but are prone to lung infections."