https://www.researchgate.net/profile/Chun_Chieh_Tseng/publication/239392662_Inactivation_of_Virus-Containing_Aerosols_by_Ultraviolet_Germicidal_Irradiation/links/54f823b80cf2ccffe9dce501/Inactivation-of-Virus-Containing-Aerosols-by-Ultraviolet-Germicidal-Irradiation.pdf
UV sterilizers do work on most all viruses from what I understand but the issue is the the further from the light source the less effective it becomes and time, temperature and humidity are all factors which can affect the effectiveness. A UV-C light strong enough to clean a 100 sq ft room would be dangerous to humans so it could only be used as a sanitary item and not on all the time. At least as far as I understand it.
edit: just saw your usage idea. Not sure it would be doable and safe for humans but packages seems totally fair game.
you dont want to use this as normal illumination, it is damaging to the eyes.
there is a system where microbiological labs are under constant intense illumination with UV while they are unoccupied. you would be doing something similar i suppose?
have look here as an example of what you would need to do a proper job:
https://www.light-sources.com/solutions/germicidal-uvc-lamps...
https://www.light-sources.com/solutions/germicidal-uvc-lamps...