How can we recognise when we have coronavirus?

Dr Elizabeth Webb, Senior Research Manager at Age UK, has an MSc in Epidemiology from the London School of Hygiene and Tropical Medicine and a PhD in Social Epidemiology from University College London. She discusses some of the others symptoms of coronavirus being identified, and what it means to be 'asymptomatic'.

The NHS currently lists 2 symptoms as early indicators of coronavirus: a high temperature and a new, continuous cough. This particular combination of symptoms is quite unique and characteristic of coronavirus, and can help us identify it as different from the other coughs and colds that are going around.

As well as the high temperature and cough the NHS tell us to look out for, the World Health Organisation (WHO) also mentions tiredness and other symptoms that may be experienced by some people with coronavirus: shortness of breath, aches and pains, sore throat, diarrhoea, nausea, a runny nose, and a loss of smell or taste. Many of these symptoms are common to other illnesses we all often experience, so may not be so helpful in identifying people with coronavirus.

Symptoms still being identified

As coronavirus is a new disease, doctors are still identifying symptoms, and the general public isn’t familiar enough with the different ways coronavirus can be experienced to be able to identify it well without having had a test.

Coronavirus seems to have a particularly wide range of severity, from people who have no idea they’ve had it right through to the people who have respiratory failure and, sadly, die. We have heard about lots of people who have coronavirus being ‘asymptomatic’ – that is, they are not experiencing symptoms of coronavirus. Some early research has suggested up to half of people with coronavirus are asymptomatic.

An age pattern in symptoms

There is an age pattern to the most severe cases of coronavirus. Data released by the Office for National Statistics shows there were 11 coronavirus deaths for every million people in England and Wales up to 27 March. However, among people aged under 65 there were 2 per million, while for 65-74 there were 20 per million, 60 per million for 75-84, and 161 per million for 85+.

It's likely that the age pattern in being asymptomatic will be the opposite of that we see with deaths: those who are younger, who are less likely to have severe illness from coronavirus, will probably be the most likely to be asymptomatic. One of the reasons we’re all being asked to practice social distancing is because even if someone doesn’t have coronavirus symptoms, they may still be able to pass it on.

Asymptomatic, or experiencing different symptoms?

There is emerging evidence that some of these ‘asymptomatic’ people aren’t actually experiencing no symptoms, they’re just not experiencing the symptoms that we’ve all been looking out for. You may have seen it reported in the news last week that some new evidence on loss of taste or smell as possible symptoms of coronavirus.

A team of scientists from Kings College London have asked members of the public to give them a daily update on any symptoms they have using a smartphone app. 2 million people have answered questions on how well they feel, whether they have had a coronavirus test, and whether it came back positive. Of the 1,702 people who said they had a test, 579 tested positive.

Loss of smell or taste

The finding that surprised the Kings team was that nearly 6 in 10 (59%) of those with a positive coronavirus test result said they had experienced a loss of smell or taste, compared to only 1 in 5 (18%) of those who had a negative test. Scientists from South Korea, China, Italy and Germany have also noted loss of taste and smell as symptoms of coronavirus. There are some suggestions that loss of smell or taste is particularly common among people with coronavirus who have few other symptoms.

It’s really important that everyone is on the lookout for unusual symptoms of coronavirus, including loss of smell and taste. Even if we are at low risk of severe illness ourselves, it is important to realise when we might have coronavirus, to self-isolate, and to avoid passing it on to those who are at higher risk of severe illness. If you have been helping an older or other high risk person, for instance with shopping, and experience these symptoms please consider asking someone else to help them until you can be sure you are not contagious.