Scent-trained dogs may help screen COVID-19 rapidly in noninvasive manner

A subset of volunteer schools where antigen testing was scheduled was selected. Keeping the participants 6 ft apart, the dogs, led by handlers, sniffed the participants’ ankles and feet. Handlers were alerted by the dogs by sitting near the participant with potential COVID-19 infection. Participants then underwent BinaxNOW (Abbott) antigen testing. A digital platform was used to record the dog and antigen results. 

If a dog signaled positive and antigen testing results were negative, the signal was considered falsely positive; similarly, if a dog did not signal and antigen testing results were positive, the signal was considered falsely negative. 

Key findings: 

• Nearly 50 visits were conducted at 27 schools from April 1 to May 25, 2022. 
• There were 1558 participants with 89% students. Nearly 68% were screened at least twice. 
• About 3897 paired antigen-dog screenings were completed. 
• The dogs signaled 85 infections accurately and ruled out 3411 infections with an overall accuracy of 90%. 
• They inaccurately signaled infection in 383 instances and missed 18 infections, resulting in a sensitivity of 83% and specificity of 90%. 

Thus, the authors suggested that by making small alterations in the procedure, dogs can be used for efficient and noninvasive COVID-19 screening and also for other pathogens.

Further reading: Glaser CA, Le Marchand CE, Rizzo K, et al. Lessons Learned From a COVID-19 Dog Screening Pilot in California K-12 Schools. JAMA Pediatr. Published online April 24, 2023. doi: 10.1001/jamapediatrics.2023.0489