Menopausal women may be unfairly denied entry to airports, pubs and restaurants if they have their temperature checked, it is feared.
Temperature detection devices — used in the fight on coronavirus — measure heat in the skin, which experts say can spike during a ‘hot flush’.
Doctors behind an app for women going through say hot flushes could be mistaken for having a fever — a tell-tale symptom of Covid-19.
Dr Ornella Cappellari, of Meg’s Menopause, said: ‘It is paramount to put in place measures which will allow menopausal women unbiased treatment when entering places such as airports because they may be experiencing a physiological reaction.’
Temperature detection devices, such as handheld forehead scanners being used in restaurants and offices, are not considered reliable for spotting coronavirus.
The gadgets are not accurate at measuring the core body temperature and only give a rough estimate, scientists say.
And some people with Covid-19 never develop a high temperature, therefore would be allowed to breeze through temperature checks despite being contagious.
Menopausal women are feared to be unfairly denied entry to airports, pubs and restaurants if they get their temperature checked by scanners. Heathrow has started trialling temperature screening of passengers (pictured)
Temperature check devices work by measuring the temperature of the skin, so in theory, would detect the changes caused by a hot flush. They do not measure the body’s core temperature. Pictured, a nurse taking a travellers temperature at Sydney Airport
Putting a thermometer into an armpit, mouth, ear or other body cavity is known to be the most accurate way to measure temperature.
It gives a reading for the body’s core temperature, which may rise in order to help fight illness. A high temperature is regarded as anything within the range of 38°C and 41°C.
Temperature scanners — including thermal imaging and temperature ‘guns’ pointed at the forehead — do not measure the body’s core temperature.
HOW DO TEMPERATURE CHECKS WORK?
Temperature checks are done with either portable ‘guns’ pointed at the forehead or with thermal imaging cameras.
Both detect heat being radiated from the skin using infrared sensors.
Thermal cameras detect heat radiating from the body using infrared technology and estimate the core temperature. They measure heat distribution across the body.
Portable devices also use infrared sensors to detect skin temperature changes, but do not provide an image. They measure temperature in one spot, usually from the head, and give a number on screen.
However, both pieces of kit can only give an idea of temperature of the skin, and not inside the body, which is what a thermometer would do.
Therefore they are not as accurate as a medical device which takes a patient’s’ temperature.
But they may have some usefulness during the Covid-19 pandemic for spotting potential sick people.
If a person is flagged as potentially having a high temperature, they may be denied entry to a venue. But this would depend on the policy of each place.
They are controversial because a temperature above the normal range does not necessarily mean someone has the coronavirus – they may be unwell with something else. And people have variations in their temperature daily and women see fluctuations through their menstrual cycle.
They can also miss Covid-19 patients who do not have the symptom of a high temperature, or not symptoms at all.
The World Health Organization says thermal camera says temperature screening ‘may not be very effective’ as a singular tool for detecting Covid-19.
Instead, they measure skin temperature which, although tends to correlate with spikes in core body temperature, can vary depending on the environment and activity.
The devices can only make an estimation of core body temperature by measuring heat radiating from the skin using infrared technology.
For this reason, Dr Cappellari fears menopausal women will be picked up if they are having a hot flush.
A hot flush — which can last for several minutes — causes the skin to heat up.
It starts when blood vessels near the skin’s surface widen in an attempt to cool the body down.
Scientists believe the process is triggered by fluctuation in hormone levels, which drastically change during the menopause.
Dr Cappellari, a former University College London researcher, said: ‘Most women experience hot flushes, which can cause a rise in skin temperature detectable by Covid-19 temperature checks.
‘The menopause is a delicate phase of transition for most women. You can sail through it very easily — or not.’
Derek Hill, a professor of medical imaging science from University College London, agreed that a thermal camera may wrongly flag a hot flush as a high temperature.
He told MailOnline: ‘Hormonal changes results in blood vessels dilating. The thermal camera might pick it up because the blood goes to the skin.’
But he insisted that it was unlikely because temperature checks often focus on the forehead — the most clearly exposed area of skin.
Hot flushes tend to centre around the chest and neck, which are often covered by clothing, Professor Hill said.
Professor Hill added that it was unlikely any action would be taken against women going through the menopause for a number of reasons, and therefore is ‘not something to worry about’.
Firstly, if they were taken aside for further investigations, a thermometer would prove they do not have a fever.
And he said a hot flush will be over quicker than the time it takes for a thermometer check to be taken. A fever, on the other hand, is prolonged.
Professor Hill added that thermal imaging cameras are not designed to look for people who potentially have a fever, and are used more traditionally in medical research.
‘They aren’t designed or tested to do this,’ he said, adding that they are not medically approved, either.
An expert in medical imagine science admitted temperature detection devices may flag women having a hot flush as a potential Covid-19 case, but would unlikely result in any action (Fiumicino airport, Italy)
MHRA SAYS TEMPERATURE SCANNERS CANNOT DIAGNOSE COVID-19
The UK medicine health regulators warned in July that thermal cameras and other such ‘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 Medicines and Healthcare products Regulatory Agency (MHRA) urged for manufacturers and suppliers of thermal cameras to avoid making such claims.
There is little scientific evidence to support temperature screening as a reliable method for detection of Covid-19 or other febrile illness.
Temperature readings come from measuring skin temperature rather than core body temperature. In either case, natural fluctuations in temperature can occur among healthy individuals.
Furthermore, infected people who do not develop a fever or who do not show any symptoms would not be detected by a temperature reading and could be more likely to unknowingly spread the virus.
Graeme Tunbridge, MHRA Director of Devices, said: ‘Many thermal cameras and temperature screening products were originally designed for non-medical purposes, such as for building or site security. Businesses and organisations need to know that using these products for temperature screening could put people’s health at risk.
‘These products should only be used in line with the manufacturer’s original intended use, and not to screen people for COVID-19 symptoms.’
Health Minister Lord Bethell said: ‘As pubs and restaurants begin to reopen, it’s important businesses do not rely on temperature screening tools and other products which do not work.
‘The best way to protect customers and minimise the risk of catching the virus is to always follow social distancing guidelines, wearing a face mask on public transport and enclosed public spaces, and regularly washing your hands.’
They can produce wrong results — either a ‘false positive’, when someone is detected as having a fever when they do not — or a ‘false negative’ — when they do have coronavirus but are not detected.
It can take several days for infected patients to develop a fever, meaning they may not show up on the devices. Some never develop a fever at all.
Therefore, they could be allowed entry into places while they are infectious.
Considering the inaccuracies, Professor Hill believes it is unlikely venues will be allowed to turn people away based solely on the readings of no-contact temperature scanners.
But it cannot be ruled out that some supermarkets and workplaces may deny entry if the a person’s reading is even suggestive that they have a fever.
The medicine regulator in the UK recently stressed that temperature screening products cannot be used to diagnose Covid-19 because there is not evidence to support their use — and reminded suppliers of they should not make such claims.
Health Minister Lord Bethell said in July: ‘As pubs and restaurants begin to reopen, it’s important businesses do not rely on temperature screening tools and other products which do not work.’
Temperature scanners are now in place at some UK travel ports, including Bournemouth Airport and Portsmouth ferry port, and are being trialled elsewhere.
Heathrow is currently testing thermal imaging in terminal 2 and will feed the results to the UK government.
It says for now there will be no action against holiday-makers who are detected.
However, when the trial launched in May, John Holland-Kaye, chief executive of Heathrow Airport, told BBC Radio 4’s Today the technology ‘could be part of a future common international standard to get people flying again’.
Professor Hill said there will be many people who disagree with this because thermal imaging is not a reliable measurement of body temperature.
But he added: ‘Many people would argue, and I’d be one of them, it’s not necessarily wrong to use these device this way for mass reading.
‘But you’d be much better to measure it with an infrared thermometer [one entered in the ear] with a CE mark.
‘They certainly shouldn’t be used to say if someone has a fever. But they might be useful for detecting people who need a real temperature check.’
Alex Casson, an electrical engineer at the University of Manchester, said thermal scanners are not very sensitive.
He told MailOnline: ‘They’re only accurate to around 0.5 degrees so very difficult to get precise readings.’