Trained sniffing dogs can detect infected SARS-CoV-2 with high accuracy. Article on this subject by Finnish scholars published Works at BMJ Global Health
Dogs’ sense of smell is highly sensitive: these animals can detect concentrations of substances in parts of a trillion, which is significantly superior to the result of most artificial methods. Dogs, in particular, can sense volatiles released by the body during illness or parasite damage.
In preliminary studies, it was found that dogs could be trained to detect coronavirus patients within two weeks with an accuracy comparable to a PCR test. To test this, scientists trained four dogs during the spring 2020 pandemic wave.
420 human volunteers provided skin swab samples. Of these, 114 were diagnosed with coronavirus using PCR testing. Samples were shown to the dogs during seven testing sessions.
It turned out that the accuracy of coronavirus diagnosis using dogs reached 92 percent, and the specificity was 91 percent. The most successful dogs achieved 93 percent accuracy and 95 percent specificity, while the least successful dogs achieved 88 percent and 90 percent, respectively. Then, dogs were tested at Helsinki-Vantaa airport in Finland, the detection of patients with covid using animals and the results of the PCR test were 98 percent consistent.
Thus, this method allows reliable diagnosis of SARS-CoV-2 infection.