Early in 2020, before diagnostic tools were widely accessible, the idea of using dogs to detect COVID-19 surfaced. 

Since then, more than 70 groups in 60 countries have conducted research to determine how and whether canines may be used to detect those with SARS-CoV-2 infection. 

Dogs were evaluated for their capacity to recognize COVID-19 from sweat samples, saliva, masks, and urine in the 27 studies that made up this analysis. 

Sensitivity and specificity ranges in six trials with high-quality data were 82% to 97% and 83% to 100%, respectively.  

Rapid antigen testing should have minimum standards that are higher than 80% sensitivity and 97% specificity. 

According to the systematic review done, most SARS-CoV-2 canine smell detection is within or even above these requirements.

Dogs have been thus utilized in real-time population screening scenarios, such as airports and large gatherings because they can detect scent in seconds.