New filtration system for commercial airliners are available that use electric field to remove up to 99.9% of infectious diseases and pollutant from aircraft air.
This is vitally important, as many of the flu germs, viruses, and other contagious diseases are transmitted through the systems that recirculate aircraft air many times per hour.
Investment in the new filtration equipment can cost from 10000 to 15000 per aircraft, but saving in fuel, customer complaints, legal actions, etc., can also be sizable.