COVID from the viewer’s eye: Montreal’s research supports the development of new detectors

Montreal-Many people are now accustomed to the idea that guards may stop at the entrance to a hospital, store or airport while they are measuring their temperature.

Portable infrared temperature readers are usually aimed at the forehead, and unless heat is recorded on the screen, McGill University researchers say the process is “significantly flawed,” but the person has access. Is allowed.

“Measurements on the forehead are not accurate,” said Dr. Jose L. Ramirez-Garcialna, a postdoctoral fellow in surgery.

There, Ramirez Garcia Luna of Magill’s School of Medicine and his colleagues work with a team in Mexico to help identify people who are infected with COVID-19 but have minimal symptoms. I looked to see if I could find a way.

Results of a recently published small study European Journal of Clinical InvestigationResearchers suggest that by registering the temperature of a person’s eyes using infrared thermal images, it is possible to more accurately determine who is ill and who is not. Said in an interview.

“From the pilot project, I’m sure it could be a screening method,” Ramirez-Garcialna said, but “there is still a lot of research to be done before we deploy it. I think.”

The temperature of the forehead is capricious

Doctors said using a traditional fever screening forehead thermometer was better than not screening at all, but concluded that it was of limited value for several reasons.

Unless the thermometer is placed on the armpit, mouth, or eardrum, “it is the temperature of the skin that is being measured, not the temperature of the center of the body,” the researchers explained.

The core temperature of all humans is very stable at around 37 ° C, but this is important because skin temperature varies widely from person to person and varies with factors such as weather, physical activity, and hormone levels.

The second defect is due to the assumption that heat is a good indicator of COVID-19. “But not everyone with COVID has a fever, and even if they have a fever, they don’t always have it,” says the researcher. Said.

In addition, some “commercial thermometers may not be sensitive enough to detect small changes in temperature.”

Eyes-a window to the infectious process

In this study, conducted in Mexico, 60 patients were enrolled and their faces were scanned with a thermal imaging camera to capture all the heat released by the bloodstream or inflammation.

Subjects were divided into three groups, the first group being regularly examined and consisting of hospital staff without COVID.

Another group consisted of people who showed mild symptoms after close contact with the infected person.

All of them were divided into COVID-positive or COVID-negative groups, depending on the results of their PCR tests.

“If you take an image of a sick person, you can find out where the inflammation is occurring,” said the researcher, especially “with COVID, the virus goes into the eyes and certain tissues in the eyes.”

As the researchers expected, the eyes of sick people glowed bright red in the captured infrared images. A combination of inflamed blood vessels and reactions caused by the virus.

Next, I compared the temperature of my forehead with the temperature of my eyes.

“We found that the difference in temperature distribution between the forehead and the eyes was more than 0.55 ° C, which was very suggestive of COVID infection,” said Ramirez Garcia Luna.

Future feasibility

According to doctors, face and eye heat scans to detect active COVID-19 infections could be a future path at subway station entrances, grocery stores, or where there are large gatherings. There is.

The portable device itself is inexpensive and easy to use by connecting it to your mobile device.

However, researchers emphasized the need for more evidence to confirm the results and how to control different environments and different mobile cameras.

Since I was at the airport with other types of scans, I also need to address privacy concerns about taking images of people’s faces.

But he said other health crises would eventually occur, and during this pandemic “using the lessons learned” would “use technology” to solve the following problems: It is important for him to think that it is “finding an innovative way to take advantage of it.”