1. Institute of Medical Virology, University of Zurich , Zurich, Switzerland
2. Environmental Chemistry Laboratory, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, Switzerland
3. Institute for Atmospheric and Climate Science, ETH Zurich , Zurich, Switzerland
4. Laboratory of Atmospheric Processes and Their Impacts, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, Switzerland
5. Institute of Chemical Engineering Sciences, Foundation for Research and Technology Hellas , Patras, Greece