people with loss of smell and taste appear to be three times more likely to have contracted COVID-19 according to our data
The easiest way to know whether you have COVID-19 could be to lose your sense of smell and taste, according to a study of data obtained from a symptom tracker app built by scientists in the United States and the United Kingdom to help monitor and control the coronavirus pandemic.
According to the research, nearly 60% of patients who were eventually tested positive for COVID-19 have reported losing their sense of smell and taste, compared to 18% who tested negative.
Such findings, which were released online but not clinician-reviewed, were much better than self-reported fever in forecasting a successful COVID-19 diagnosis, scientists at King’s College London said.
The app, which the experts claim could help slow down the epidemic and recognize people at risk of contracting COVID-19 more easily, can be accessed from the covid.joinzoe.com.
When enough users are interested in reporting their symptoms, the scientists said, the software might offer highly useful knowledge for healthcare services as well.
“This app-based study is a way to find out where the COVID-19 hot spots are, new symptoms to look out for, and might be used as a planning tool to target quarantines, send ventilators and provide real-time data to plan for future outbreaks,” Andrew Chan, a co- professor at Harvard Medical School in the U.S. said.
1.5 million app users registered one or more symptoms via the app between March 24 and March 29, 26 per cent. Of these, 1,702 were also confirmed to have been tested for COVID-19, with 579 positive and 1,123 negatives. Using all the collected data, the research team built a statistical model to determine the mixture of symptoms-ranging from loss of smell and taste, to cough, temperature, tiredness, diarrhoea, stomach pain was most effective in predicting COVID-19 infection.
“When combined with other symptoms, people with loss of smell and taste appear to be three 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,” said Tim Spector (King’s professor who led the team).
Trish Greenhalgh, a primary health sciences professor at Oxford University in the U.K. and not participating in the research, said it was the first to show statistically and in a significant population sample that smelling deficiency is a signature function of COVID-19.
Tim Spector team extended their research to the more than 400,000 individuals who were reporting symptoms through the app who have not yet seen a COVID-19 test and noticed that about 13% are likely to be compromised.
That would mean that some 50,000 people in the U.K. might have COVID-19 infections as not yet confirmed, Tim Spector further said.