There have been numerous measures put in place to ensure the safety of people as the battle against the novel Coronavirus continues throughout the globe and one of the most prominent tool used in public places are the infrared thermometer which are usually placed on people’s forehead to assess their body temperature which is meant to identify whether someone has the coronavirus or not.

Ever since the first outbreak back in 2020, a lot has changed concerning how the coronavirus is being detected in people as well as testing methods or even researches. It’s thought that a sudden increase in the body temperature could be linked to the coronavirus which is why different institutions have deployed these infrared thermometers across multiple places and locations.

The technology behind the thermometer allows for a digital calculation of the body temperature under milliseconds compared to the olden mercury type used in the 80s. These infrared thermometers are also non-invasive but the accuracy of these devices have come under serious questioning.

A report has stated that about 11% of people who tested positive to the COVID-19 do not have any high body temperature even though fever have been linked to the COVID-19 as one of the many symptoms of the illness.

Speaking on accuracy, the big question as to whether placing the infrared thermometer on people’s head is enough to detect the entire body temperature is under question. Although there are instances whereby an increase forehead temperature can show a raised deep body temperature which is why the forehead is the go to place for the placement of the infrared thermometers.

However, there are chances that the forehead or even skin temperature can be increased or decreased independently of deep body temperature for many reasons. There are situations such as being in hot environment, getting sunburned or exercising or too much clothes, taking alcohol, eating and other situations can cause an increase/decrease in the skin temperature.

With these factors, the results of these tests sometimes could be false whereby a suspected increase in the body temperature might be due to the aforementioned situations. While a safe pass might not just be the right to do if the body temperature is normal, the need to be sanitized as often as possible becomes pretty important as this allow people to stir clear of spreading or contracting the coronavirus in public places.

All of the above has led the European Center for Disease Prevention and Control to conclude that, although some COVID-19 cases do get detected through temperature-screening procedures at airports, evidence indicates that such measures, on the whole, aren’t effective.

In the UK, the Medicines and Healthcare Products Regulatory Agency has similarly warned that “temperature screening products, some of which make direct claims to screen for COVID-19, are not a reliable way to detect if people have the virus.” The Canadian Agency for Drugs and Technologies in Health also noted years ago that “the accuracy of infrared skin thermometers is equivocal and requires more research.”

More to be done

The speed of the thermometer device is one of the essential reasons why it’s being deployed across multiple places but there needs to be a much more powerful and accurate way of doing this moving forward.

One of such approach includes sticking with the same test method but change how it’s being done. We know that the body’s extremities are more reactive to the overall thermal profile of the body – that fingers, for example, increase or decrease their temperature quite a lot as deep body temperature increases and decreases a little. In contrast, the head – in particular the corners of the eyes – are more consistent and reflective of deep body temperature.

Taking a better look at these parts of the body will help provide a much more accurate indication of deep body temperature caused by fever. This is because there are scenarios whereby deep body temperature increases, the temperature of the extremities also increases like instances mentioned earlier such as exercise, when drinking alcohol, getting hot when wearing too many clothes, and so on. As a result, the difference between the temperature of the eye and fingers decreases.

Speaking of the deep body temperature, there is usually a decrease in the temperature of hands and feet which is why the eye and finger temperature measurement can be a more accurate way of doing the measurement in a much more accurate way.

Therefore, a more accurate way of using infrared thermometers to screen for COVID-19 might be to measure the temperature of the hand and the corner of the eye and determine the difference.

Like many other things, this wouldn’t be an accurate approach as there could age-related conditions and many other things to consider assuming we’re trying to take the right approach in detecting the accuracy of the body temperature measurements. So its going to be a really sensible approach to basically increase the usage of hand washing, sanitizing and constant usage of face mask in order to prevent the spread of the illness from people to people as well as flattening the curve.

This article by Mike Tipton, Professor of Human and Applied Physiology, University of Portsmouth and Igor Mekjavic, Researcher in Automation, Biocybernetics and Robotics, Jožef Stefan Institute, and Adjunct Professor, Simon Fraser University is republished from The Conversation under a Creative Commons license. Read the original article.