Germany is to spend €500 million ($898m) on upgrading ventilation systems in public buildings to combat the spread of coronavirus.
Schools, universities, public offices and museums will be able to apply for grants of up to €100,000 to fit their existing air conditioning or ventilation systems with filters.
The virus is chiefly spread by aerosols exhaled by people who are infected when they sneeze or cough, and a number of new filtration systems have been developed that can stop most of the microscopic droplets.
The money is only available for public buildings in which large numbers of people gather, such as school auditoriums and theatres.
Germany has something of a national obsession with ventilating rooms and Chancellor Angela Merkel's Government is promoting the practice as part of the fight against the coronavirus.