1. Department of Infection Control and Environmental Hygiene, Cologne Health, Authority, Cologne, Germany
2. Cologne Health Authority, Cologne, Germany
3. Institute for Occupational Medicine and Social Medicine, University Hospital, Medical Faculty, RWTH Aachen University, Aachen, Germany
4. Department for Physical Activity in Public Health, German Sport University Institute of Movement and Neurosciences, Cologne, Germany
5. Institute of Hygiene, University Hospital Muenster, Muenster, Germany