Researchers believe loss of smell or taste a ‘highly reliable indicator’ of Covid-19

According to the researchers from the United Kingdom, the loss of smell or taste is a “highly reliable” indicator of the coronavirus. The researchers stressed that this should be made a global criterion for testing, tracing, and self-isolating.

For the study, researchers assessed health data from primary care centres in London. Their study was published in the journal PLOS Medicine.

Researchers carried out the study between April 23 and May 14 at the peak of the pandemic. The researchers sent text messages to people registered with a number of primary care centres in London who had reported a sudden loss in their sense of smell and/or taste.

They then recruited a total of 590 participants via a web-based platform and responded to questions about the loss of smell and taste and other Covid-19 related symptoms.

Of these, 567 had a telemedicine consultation with a healthcare professional who confirmed the history of their symptoms and supervised a test to find out if they had SARS-CoV-2 antibodies.

The researchers concluded after a cohort study that 78 per cent of people who had reported loss of smell or taste during the initial phase of the pandemic had antibodies against the virus. Of these around 40 per cent did not have a cough, cold, or fever.

Lead author professor Rachel Batterham, from University College London (UCL) Medicine and UCL Hospitals said in an official statement: “As we approach the second wave of infections, early recognition of Covid-19 symptoms by the public, together with rapid self-isolation and testing will be of vital importance to limit the disease's spread.”

She added: “Our findings show that loss of smell and taste is a highly reliable indicator that someone is likely to have Covid-19 and if we are to reduce the spread of this pandemic, it should now be considered by governments globally as a criterion for self-isolation, testing, and contact tracing.”

“While people in the UK who experience sudden onset loss of smell or taste are advised to self-isolate and seek a test, at a global level only a few countries recognize this symptom as a Covid-19 indicator: most focus on fever and respiratory symptoms,” she said.

Researchers believe that the key public health message should be: people who notice a loss in their ability to smell everyday household odours. This includes garlic, onions, coffee, and perfumes should self-isolate and seek a coronavirus PCR swab test.

The study is first of its kind to explore the symptom of loss of taste and smell as one of the preliminary symptoms of the virus. The study was funded by the National Institute for Health Research Biomedical Research Centre.

COMMENT NOW