A loss of taste and smell may be the best way to tell if you have coronavirus, new study shows

If tests are not available, a loss of taste and smell could be the best way to detect whether someone has contracted the coronavirus, according to U.K. researchers.

A research team at King’s College London assessed the responses of more than 400,000 people reporting one or more suspected symptoms of COVID-19 to an app.

The data analyzed showed that 59% of those who tested positive for the virus reported a loss of smell and taste, compared with only 18% of who tested negative for the disease. These results, the researchers said, were “much stronger” in predicting positive COVID-19 diagnoses than a self-reported fever.

This appears to indicate that a loss of smell and taste should be added to the list of common coronavirus symptoms. Until now, health authorities like the WHO have said a fever, dry cough and fatigue are the symptoms to watch out for.

The general advice for those who display symptoms of COVID-19 is to stay at home in order to reduce the risk of spreading it to others and call your health facility.

As of Monday, more than 1.28 million people had contracted COVID-19 worldwide, with 69,789 deaths, according to data compiled by Johns Hopkins University.

Researchers at King’s College London conducted the study, published April 1, to gather information that could help health experts understand the spread and progression of the virus.

Of those reporting one or more symptoms of the coronavirus to the so-called “Covid Symptom Tracker” app: more than half (53%) said they had fatigue or tiredness; 29% had a persistent cough; 28% reported shortness of breath; 18% experienced a loss of smell or taste; and 10.5% suffered a fever.

Of these 400,000 respondents, 1,702 said they had been tested for the coronavirus, with 579 receiving positive results and 1,123 receiving negative results.

Almost 60% of those who had tested positive for COVID-19 reported a loss of sense of smell and taste.

“When combined with other symptoms, people with loss of smell and taste appear to be 3 times more likely to have contracted COVID-19 according to our data, and should therefore self-isolate for seven days to reduce the spread of the disease,” Professor Tim Spector, lead researcher on the study, said in a statement.

The WHO has not added a loss of smell or taste to the list of common symptoms to the coronavirus.

The United Nations health agency states that the COVID-19 infection affects different people in different ways, with common symptoms including a fever, dry cough and tiredness. Some people may develop more severe forms of the disease, such as pneumonia, but most patients recover thanks to supportive care.

It has advised people with mild symptoms who are otherwise healthy to self-isolate and contact their medical provider or a COVID-19 information line for advice on testing and referral.

Those with a fever, cough or difficulty breathing should call their doctor and seek medical attention, the WHO has said.

Last month, ENT UK, the body that represents ear, nose and throat doctors in Britain, issued a joint statement calling for the loss of sense of smell to be recognized as a marker of the COVID-19 infection.

The specialists at ENT UK said it was “perhaps no surprise” that the coronavirus could cause infected patients to lose their sense of smell because having had a virus is one of the leading causes of loss of sense of smell in adults, accounting for up to 40% of cases.