Body temperature tests are too unreliable to detect Covid-19

A team from the University of Portsmouth found multiple inaccuracies with such a test which it says largely invalidates the results.

First, they found that temperature alone is not a good indicator of the disease, as not everyone with the virus has a fever and many develop only one after admission to the hospital. hospital.

The practice of measuring skin temperature also doesn’t give an accurate estimate of deep body temperature, and a high temperature doesn’t necessarily mean a person has Covid-19, anyway, the team said.

Taking two temperature readings – one from the finger, the other from the eye – is likely to be a better and more reliable indicator of a fever-induced deep body temperature rise.

Researcher Professor Mike Tipton said: ‘If scanners don’t give an accurate reading, we run the risk of wrongly excluding people from the places they want or need to go and we also run the risk of allowing people carriers of the virus from spreading the undetected infection they have.

“Using a surface temperature scanner to obtain a single surface temperature, usually the forehead, is an unreliable method of detecting fever associated with Covid-19.

“Too many factors make skin temperature measurement a poor substitute for deep body temperature: Skin temperature can change independently of deep body temperature for many reasons. Even though such a single measurement reliably reflected deep body temperature, other things, like exercise, can increase deep body temperature.

“The pandemic has had a devastating global effect on all aspects of our lives and, sadly, it is unlikely to be the last pandemic we are facing. It is essential that we develop a method for determining whether a person has a fever that is accurate and fast. “

The most common symptom of the 55,924 confirmed cases of Covid-19 reported in China up to February 22, 2020 was fever, followed by other symptoms, including dry cough, sputum production, shortness of breath, pain muscle or joint, sore throat, headache, chills, nausea or vomiting, nasal congestion and diarrhea.

However, researchers say that a significant proportion (at least 11 percent) of people with Covid-19 do not have a fever, and less than half of those admitted to hospital suspected of having the disease had fever. Although the majority of positive cases develop a high temperature after being admitted to hospital, they were contagious before their temperature soared.

Professor Tipton said: “We think we can improve the identification of the presence of fever by using the same kit, but looking at the difference between eye and finger temperature – it’s not perfect, but it is ‘is potentially better and more reliable. “

Last week, a team from Swansea University announced that they were developing a “ smart patch ” containing the coronavirus vaccine that can be self-administered by patients.