cologne koln germany, corona covid time: panorama of the aachener weiher lake with protection face mask

aachener background bacteria bacterium biology blood cell cologne concept corona coronavirus cov covid danger dangerous disease epidemic face flu germ germany health healthcare human illness infection infectious infographic inhale koln lake man mask medical medicine merscov micro microbe microbiology organic organism outbreak panorama prevention protection respiratory science sickness spread symbol time transfer transmit viral virus warning water weiher