1. Present address: NIHR Health Protection Research Unit in Respiratory Infections, National Heart and Lung Institute, Imperial College London, London, UK
2. Station d’Ecologie Théorique et Expérimentale, UAR2029, CNRS, Moulis, France
3. Present address: Centre for Environmental Sciences, Environmental Biology, Hasselt University, Diepenbeek, Belgium
4. Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK