Researchers from Columbia University are testing a nasal spray which provides 24 hour protection against the virus.
https://bgr.com/2020/11/07/coronavir...y-lipopeptide/
This might reassure travelers, all passengers get their nasal spray as part of the boarding process, so the virus won't spread on the plane. Obviously no panacea, does not help those already infected or solve the international travel issues, but could work for domestic routes.