Loss of smell an important symptom of Covid-19

While loss of smell and/or taste as a predictor of Covid-19 has not been well understood previously, a group of international researchers are calling for loss of smell to be globally recognised as a key symptom of the highly contagious virus.

Published in PLOS Medicine, the study involved 567 participants who reported loss of taste and smell, and found that 78% of the participants with these symptoms had SARS-CoV-2 antibodies.

The researchers also found that participants with loss of smell were almost three times more likely to have SARS-CoV-2 antibodies compared to those with loss of taste, suggesting that a loss of smell is a highly specific symptom of Covid-19.

Interestingly, of the 78% of participants who tested positive for antibodies, 40% had neither a cough nor fever.

The researchers conclude that “recent loss of smell is a highly specific Covid-19 symptom and should be considered more generally in guiding case isolation, testing and treatment of Covid-19” – an over reliance on cough and fever as the main symptoms of Covid-19 may be flawed and loss of smell should be considered as a key symptom of Covid-19.

Professor Rachel Batterham, who led the study, says: “Early self-recognition of Covid-19 symptoms by the members of the public, together with rapid self-isolation and PCR testing are vital in order to limit spread of the disease.

“Currently, most countries around the world do not recognise sudden loss of smell as a symptom of Covid-19.

“78% of participants in our community-based study with sudden onset loss of smell or taste had SARS-CoV-2 antibodies.

“The vast majority had mild symptoms and 40% did not report having a fever or cough.

“Our findings suggest that people who notice a loss in their ability to smell everyday house-hold odours such as garlic, coffee and perfumes should self-isolate and seek PCR testing.

“Loss of sense of smell needs to be recognised globally by policy makers as a key symptom of Covid-19.”

For more information and to read the study, visit: journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003358