Concerns have been raised over the accuracy of the scanners, which are usually applied to the forehead, after a new study found four key issues including the fact skin temperature is not always an indicator of body temperature.
The research, lead by physiologist and temperature regulation expert Professor Mike Tipton, from the University of Portsmouth, also determined that temperature alone was not enough to indicate disease.
Prof Tipton said: ‘Too many factors make the measurement of a skin temperature a poor surrogate for deep body temperature; skin temperature can change independently of deep body temperature for lots of reasons.’
The report, which has been published in scientific journal Experimental Physiology, suggested taking two temperature measurements, from the finger and the eye for more accurate results.
Currently a scanner is used at Portsmouth International Port and 15 are used around the University of Portsmouth campus.
Prof Tipton added: ‘If scanners are not giving an accurate reading, we run the risk of falsely excluding people from places they may want, or need, to go, and we also risk allowing people with the virus to spread the undetected infection they have.’
But Ian Diaper, the head of operations at Portsmouth International Port, said: ‘The temperature camera is just one of the tools we use to keep staff and customers safe, and isn’t used in isolation.
‘We are only alerting the fact someone has consistently registered a high temperature to the ship’s medical teams who will carry out their own assessment whether further action is required.
‘The same process applies to our staff. The camera is in place to help minimise the spread of infections or outbreaks but isn’t a diagnostic tool for Covid-19.’
And a university spokeswoman added: ‘We are committed to using the best available resources to help fight Covid and, at the time our 15 scanners were bought, they were.
‘No predictive measure for Covid-19 (or indeed any disease) is 100 per cent accurate. We are fortunate our researchers are leading the research to help save lives and will continue to work to ensure all our safety measures are the best available and are constantly improved.’
Around 11 per cent of people with Covid do not suffer a fever, it's thought.
Prof Tipton's report found existing body scanners can be ‘easily’ adapted to take two measurements per person, rather than one.