According to new studies, the loss of smell is a reliable indicator of a Covid 19 infection. Four out of five people with this symptom will test positive for coronavirus antibodies.
Scientists say loss of smell or taste should now be viewed globally as a criterion for self-isolation, testing, and contact tracing.
Researchers from UCL and UCLH (NHS Foundation Trust of University College London Hospitals) assessed health data from primary care centers in London.
They found that 78% of people who reported sudden loss of smell and / or taste at the height of the pandemic had Covid-19 antibodies.
Of these people, 40% had neither a cough nor a fever.
According to the researchers, it is the first time that such a number has been calculated.
Lead author Professor Rachel Batterham of UCL Medicine and UCLH said, “As we approach a second wave of infections, early public detection of Covid-19 symptoms, along with rapid self-isolation and testing, will be vital to limit the spread illness.
“While people in the UK who suddenly experience a loss of smell or taste are advised to self-isolate and seek a test, on a global scale, few countries recognize this symptom as a Covid-19 indicator – most are concentrating for fever and respiratory problems.
“Our results show that loss of smell and taste is an extremely reliable indicator that someone is likely to have Covid-19. If we are to reduce the spread of this pandemic, it should now be seen as a criterion for self-illness by governments worldwide . ” Isolation, testing and contact tracing. “
Prof. Batterham added, “Our research suggests that an important public health message should be: People who experience a loss of their ability to smell everyday household odors such as garlic, onions, coffee and perfumes should self-isolate and perform a coronavirus PCR swab test. “
What the study found
Between April 23 and May 14, researchers sent texts to people registered with a number of primary care centers in London who had reported a sudden loss of their sense of smell and / or taste.
A total of 590 participants registered via a web-based platform and answered questions about loss of smell and taste and other Covid-19-related symptoms.
Of these, 567 then had a consultation with a healthcare professional who confirmed the history of their symptoms and monitored a test to see if they had coronavirus antibodies.
The study published in PLOS Medicine found that 77.6% of 567 people with a loss of smell and / or taste had SARS-CoV-2 antibodies.
Of these, 39.8% had no cough or fever, and participants with odor loss were three times more likely to have SARS-CoV-2 antibodies than participants with taste loss.