Nino Künzli1,2,3, Milo A Puhan4,5, L Suzanne Suggs4,6. 1. Swiss School of Public Health (SSPH+), Hirschengraben 82, 8001, Zurich, Switzerland. nkuenzli@ssphplus.ch. 2. Swiss Tropical and Public Health Institute (Swiss TPH), Basel, Switzerland. nkuenzli@ssphplus.ch. 3. University of Basel, Basel, Switzerland. nkuenzli@ssphplus.ch. 4. Swiss School of Public Health (SSPH+), Hirschengraben 82, 8001, Zurich, Switzerland. 5. Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland. 6. Università della Svizzera Italiana, Lugano, Switzerland.