Anyone experiencing a sudden loss of smell could be a "hidden carrier" of the coronavirus, even if they have no other symptoms, according to evidence compiled by leading rhinologists in the UK.

In South Korea, China, and Italy, about a third of patients who have tested positive for COVID-19 have also reported a loss of smell – known as anosmia or hyposmia – leading ear, nose, and throat experts in the UK have reported.

"In South Korea, where testing has been more widespread, 30 percent of patients testing positive have had anosmia as their major presenting symptom in otherwise mild cases," the president of the British Rhinological Society Professor, Clare Hopkins, and the president of the British Association of Otorhinolaryngology, professor Nirmal Kumar, said in a joint statement.

The professors said that many patients around the world who have tested positive for COVID-19 are presenting only the symptoms of loss of smell and taste – without the more commonly recognised symptoms of high fever and coughing.

"There have been a rapidly growing number of reports of a significant increase in the number of patients presenting with anosmia in the absence of other symptoms," the statement says.

"Iran has reported a sudden increase in cases of isolated anosmia, and many colleagues from the US, France, and Northern Italy have the same experience."

The lack of other recognised symptoms in these cases may mean they are unlikely to be tested and isolated, meaning they could be contributing to the rapid spread of the disease worldwide.

"These patients may be some of the hitherto hidden carriers that have facilitated the rapid spread of COVID-19," they added.

Young people may not present common coronavirus symptoms

Professor Kumar told Sky News that younger patients in particular may demonstrate only a loss of smell or taste, without demonstrating the more commonly recognised coronavirus symptoms of high fever and persistent coughs.

"In young patients, they do not have any significant symptoms such as the cough and fever, but they may have just the loss of sense of smell and taste, which suggests that these viruses are lodging in the nose," he said.

The professors called for anyone presenting the symptoms of loss of taste or smell to self-isolate for seven days to prevent the further spread of the disease.

This article was originally published by Business Insider.

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