It seems sniffer dogs can detect covid. Now, correct me if wrong, but smell is a sensor detecting certain chemicals yes? If this is true, then we can build a sensor to detect covid yes?
Billions have been spent on R&D in the chase for an effective vaccine. The magic "silver bullet" vaccine (like polio) has not been created yet. So I'm wondering, how much money for R&D into developing covid detectors have been spent?
I think an accurate covid detector would be more useful and practical than an attempt to vaccinate every human on Earth, unless a vaccine as effective as the polio one is discovered.
I covid "scanner" could ensure safe workplaces and detect those who shed virus instantly. Be very useful.

[nature.com]