DUBAI—Police in Dubai have built up a special unit of 38 sniffer dogs that can detect COVID-19 from human sweat samples with 92 percent accuracy, the supervisor of the training program told Reuters. Dubai Police trained the cohort, which includes German Shepherds, Labradors, Cocker Spaniels and Border Collies, to recognize the scent of COVID-19 using samples of sweat from people with confirmed infections, collected by holding a swab in an armpit for a few minutes. “A very small amount of that is then put into a jar—it has the scent of the patient—then we put the sample out for the dog to sniff … When he gives us a sign, we give him a treat,” said First Lieutenant Nasser al-Falasi of Dubai Police, supervisor of the program at the K9 training center in Dubai’s Awir region. In the center’s large training hall, police handlers walk the dogs along a row …