By Janet Coulter, MSN, MS, RN, CCM

Can dogs be trained to identify an olfactory scent of the coronavirus? Could this be a quick screening method to identify persons with COVID-19? In 2020, scientists started exploring the possibility of training dogs to sniff out the Covid-19 virus.

Miami International Airport had a pilot program with the Global Forensic and Justice Center of Florida International University. The two dogs, Cobra, a Belgian Malinois, and One Betta, a Dutch Shepherd, were in the pilot study. They were trained to sniff the masks of American Airlines employees as they made their way through the security checkpoint. If the dogs smelled a specific scent, they would sit down which signaled their handlers of a possible COVID-19 case. Their detection rate was greater than 98%.

This project started with “medical detector dogs” - dogs that could detect the odor of someone having a seizure, diabetes, and some cancers. The dogs were trained to detect one odor among many and then they were trained on a specific odor. According to the United States National Center for Biotechnology Information (NCBI), the body of a sick human being releases specific volatile organic compounds (VOC) as a result of metabolic changes. These compounds are exhaled with every breath.  Covid-19 infected people have a unique VOC with a distinct odor which can be identified by trained dogs. To train Cobra and One Beta on COVID-19 odors, masks were acquired from people hospitalized with COVID-19 and masks from people who did not have COVID-19. Testing was done on both groups of masks which discovered exhaled components trapped in the masks. To protect the dogs from possible infections, any trace of active COVID-19 virus was destroyed by ultraviolet light. While in training, every time a dog accurately selected a mask from a COVD-19 positive patient, they were rewarded with access to a red ball, a favorite toy the dogs liked to chew.  Because of their accuracy rate, Cobra and One Betta spent a lot of time enjoying their favorite red ball!

Florida International University also conducted a double-blind study with four trained dogs that showed a 97.5% accuracy in spotting Covid-19 by sniffing people and surfaces. Similar studies have been conducted in London and Germany with 94% accuracy. If a dog sits during the mask sniffing task, the mask owner is tested. Between August 23, 2021, and September 8, 2021, the dogs screened 1,093 people during 8 working days. Only one case was alerted. That person had tested positive for Covid-19 2 weeks earlier, had quarantined and was returning to work after the quarantine. Their rapid test after the dog alert was negative.

Three school districts in Massachusetts have begun using trained dogs to detect Covid-19 in classrooms. The Bristol County Sheriff's office worked with Florida International University to train two 14-month-old dogs, Huntah and Duke. The dogs sit down when they smell Covid-19 on the surface of items such as desks, keyboards, and auditorium seats. Although the dogs are not checking students individually, they can detect the odor, find out who's been in the seat or used the keyboard and contact that student's parents to see if they want a COVID-19 test.

If the dog’s detection rates continue to be highly successful, this program could be used in many other places. There have even been reports of the dogs alerting before the COVID-19 test showed a positive result. Although training can take 6-8 weeks, Covid-19 sniffing dogs should be considered a cost-effective way to ensure detection of the virus. It could speed the fight against COVID-19!

Note: The FDA has not approved this as a diagnostic tool.


Stay up to date with CMSA's COVID resources: