What your doctor is reading on Medscape.com:
APRIL 21, 2020 — As evidence piles up documenting a sudden loss of smell and/or taste as a presenting symptom of COVID-19, the call to screen for these phenomena is growing.
A number of new publications show a high proportion of people infected with COVID-19 report loss of smell and/or taste, with their authors adding to the clamor to recognize these symptoms as potentially indicative of the infection.
In particular, there is a belief that these signs may be present in many with asymptomatic COVID-19, and therefore asking about them could be a way to prioritize people for initial testing for the SARS-CoV-2 virus in the absence of other symptoms.
Despite this, the World Health Organization (WHO) has not listed loss of smell or taste as potential symptoms of SARS-CoV-2 infection.
But the US Centers for Disease Control and Prevention (CDC) has now added “new loss of taste or smell” as a symptom on its COVID-19 information page.
American Academy of Otolaryngology—Head and Neck Surgery (AAO-HNS) executive vice president and CEO James C. Denneny III, MD, believes the symptoms may be an early warning signal.
And there’s no downside to checking for these, Denneny told Medscape Medical News.
“Given the fact that this doesn’t require any surgical procedure, biopsy, or specific treatment, I think the upside of getting it early is great,” he said. “The downside of using it as a symptom, and if someone doesn’t turn out to have it, is virtually zero.”
Claire Hopkins, MD, president of the British Rhinological Society, and colleagues, writing in Lancet Infectious Diseases, agree.
“Physicians evaluating patients with acute-onset loss of smell or taste, particularly in the context of a patent nasal airway, should have a high index of suspicion for concomitant SARS-CoV-2 infection.”
They also observe that this appears to occur, in contrast to other respiratory infections, “in the absence of nasal congestion or rhinorrhea.”
Newest Publications Find Smell and Taste Loss Is Common
Author of one of the newly published studies, Carol H. Yan, MD, an otolaryngologist and head and neck surgeon at the University of California San Diego, also thinks that sudden smell and taste loss seem to be fairly specific markers of COVID-19.
In her survey of patients who presented to UC San Diego Health for SARS-CoV-2 testing, Yan and colleagues reported that 68% (40 of 59) of COVID-19-positive patients reported olfactory impairment and 71% (42 of 59) reported taste impairment.
Among the 203 people in the “control” group who were PCR-negative for SARS-CoV-2, just 16% had smell loss and 17% had taste loss, according to their results published in the International Forum of Allergy & Rhinology.
“Based on our study, if you have smell and taste loss, you are more than 10 times more likely to have COVID-19 infection than other causes of infection. The most common first sign of a COVID-19 infection remains fever, but fatigue and loss of smell and taste follow as other very common initial symptoms,” said Yan.
“We know COVID-19 is an extremely contagious virus. This study supports the need to be aware of smell and taste loss as early signs of COVID-19.”
Yan told Medscape Medical News that another not yet published analysis indicates that sudden loss of smell or taste “may be more representative of a mild form of disease.”