Around a third of people infected with COVID-19 show no symptoms – which makes it hard to know whether or not they have the virus.
While the main COVID-19 symptoms are familiar to most of us, experts say your nails and earlobes can be a key indicator in discovering infections.
The UK’s NHS states that the three main signs of coronavirus are a loss of taste and smell (anosmia), a new persistent cough and a high temperature, The Sun reports.
If you have any of these symptoms you should get a test and self-isolate.
Other people who have contracted the virus have however experienced a range of symptoms such as fatigue, headaches and breathlessness.
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COVID-19 is a virus that attacks the lungs, which is why some people feel breathless and in some cases, end up on ventilation to help them breathe.
The virus can cause oxygen levels to fall.
Patients with the condition known as “happy hypoxia” will display oxygen levels low enough to cause death or unconsciousness.
Earlier this year patients attending hospital emergency departments in the UK had been presenting with oxygen percentage levels in the 80s or 70s and some have even had levels below 50 per cent.
A healthy person would have at least 95 per cent oxygen saturation.
The key to finding your oxygen levels can be found in the earlobes and the finger nails.
This is because devices used to monitor these levels have to be clipped to either your earlobe or your finger nails in order to get a reading.
Oximeters can be used to measure these levels and can costs around £20 ($A35) to £30 ($A52).
The sensors are painless and shine a light on your nail or earlobe.
This then measures how much oxygen is in your blood.
It measures the total amount your blood can carry and is marked out of 100.
The experts behind the COVID Symptom Study app say that if you have COVID then a medical expert could give you the device to use at home so that you can monitor your blood oxygen levels.
The levels recorded can then help determine whether or not you need to go to the hospital.
The experts state: “Be wary of buying a pulse oximeter online or relying on the oxygen monitoring function of a smartwatch (sometimes known as the SpO2 sensor) as these may not be accurate.
“If it is between 92 and 94 per cent, seek advice from your GP.”
They advised heading straight to hospital or calling an ambulance if it remained below 92 per cent.
The experts do warn though that some people might have high levels due to underlying health conditions.
The say that issues such as chronic obstructive pulmonary disease or anaemia could cause your levels to fluctuate more than others.
It also states: “Cold temperature and extreme altitude can also reduce the oxygen levels in your blood.
“If you have Chronic Obstructive Pulmonary Disease (COPD), your oxygen saturation target could sometimes be lower- between 88 per cent and 92 per cent.
“Find out your target from your latest respiratory clinic letter or seek advice from your GP.”
The experts say there are other ways to look after your health during the coronavirus pandemic.
Dr Chase Ng Peng Yun said while most people won’t become seriously ill with COVID-19 there are other ways, aside from an oximeter, to monitor your health.
He said measuring your heart rate and taking your temperature regularly would help you pick up on any irregularities that might occur from COVID-19.
Dr Peng Yun urged people to also log their health in general, as this can help you spot when something isn’t right with your health and wellbeing.
This article originally appeared on The Sun and is republished with permission.