The pandemic is literally going to the dogs but, in this case, that’s not a bad thing.
“Scent-trained dogs are a strategy for rapid, noninvasive, low-cost, and environmentally responsible COVID-19 screening” according to a new study published this week in JAMA Pediatrics by Dr. Carol Glaser, the assistant deputy director in Central Laboratory Services and medical officer for infectious disease laboratories at the California Department of Public Health. Dr. Glaser, who is both a medical doctor and a doctor of veterinary medicine, had been in the process of implementing a school coronavirus testing program using antigen nasal swab tests, heard reports describing how dogs were being used to screen for the virus at airports and other public venues and had an “aha” moment.
She enlisted the assistance of two medical alert dogs from Early Alert Canines and the dogs were trained to detect volatile organic compounds emitted by people with SARS-CoV-2 (and yes, when you last had Covid, you, too, were emitting VOCs).
The dogs – Rizzo and Scarlett – were trained in a lab for two months using the socks donated by people, some who had had SARS-CoV2. The dogs’ trainers used positive reinforcement training in which dogs receive rewards for desired behavior. In this case, Rizzo and Scarlett, two yellow Labradors, received either Cheerios or liver treats and eventually achieved “greater than 95% sensitivity and specificity for detection of the virus,” the study’s authors wrote.
The researchers conducted 50 field visits at 27 schools in the period April to May 25, 2022, and a total of 1,588 participants were tested. The participants were asked to stand 6’ apart and typically were behind a screen or curtain for privacy. Only their feet were accessible to Rizzo and Scarlett, who had been trained to sit when detecting a potential case of SARS-CoV-2.
In their findings, Dr. Glaser and her colleagues wrote that their goal was to use the dogs for screening and then only use antigen tests on suspected positive cases. This brought the total number of antigen coronavirus tests down by 85%.
The dogs did indicate 383 false positives and missed 18 cases but Dr. Glazer said that their accuracy increased as they spent more time in school environments, which shows that the dogs were also in school to learn.
Jonathan Spira contributed reporting to this story.
(Photo: Accura Media Group)