In Finland there has been started research where they train dogs to scent any possible virus traces in human urine. Well...not to detect any viruses itself but possible traces of any by product chemicals from those patients known to been infected with corona. Although it takes several weeks to train already experienced sniffer dogs to any new scents, first trials are proving very promising indeed..."they detect the signs very quickly and precisely'. They are now trying to find out how 'diluted' infection signs dogs can detect..eg. how long after the patients getting well the signs are still sniffable. Link to the article in Finish press; Koira haistaa koronaviruksen nopeasti ja ällistyttävän tarkasti - voi mullistaa testaamisen Dogs are so wonderful animals...and they have so 'clever' noses!