A loss of a sense of smell or taste may be a symptom of COVID-19, medical groups representing ear, nose and throat specialists have warned.

Citing a growing number of cases around the globe, the American Academy of Otolaryngology – Head and Neck Surgery and ENT UK each issued warnings about patients who tested positive for the new coronavirus with the only symptom being a lost or altered sense of smell or taste.

"Anecdotal evidence is rapidly accumulating from sites around the world that anosmia and dysgeusia are significant symptoms associated with the COVID-19 pandemic," the American Academy of Otolaryngology – Head and Neck Surgery wrote in a statement.

Get daily coronavirus updates in your inbox: Sign up for our newsletter now.

Anosmia is the loss of smell while dysgeusia is an altered sense of taste.

South Korea, China and Italy have all reported "significant numbers" of known COVID-19 patients with lost or reduced sense of smell, according to joint statement by Claire Hopkins, president of the British Rhinological Society, and Nirmal Kumar, president of ENT UK.

"In Germany it is reported that more than 2 in 3 confirmed cases have anosmia. In South Korea, where testing has been more widespread, 30% of patients testing positive have had anosmia as their major presenting symptom in otherwise mild cases," they wrote.

Live updates:What to now about coronavirus today

The American Academy of Otolaryngology – Head and Neck Surgery advised that these symptoms should be added to the list for screening patients for possible COVID-19 infection, and ENT UK said the symptoms should signal to health care professionals treating a patient to wear full personal protective equipment.

While another viral infection or seasonal allergies could cause the loss of smell or taste, experiencing the symptoms without other respiratory illnesses warrants "serious consideration for self-isolation and testing of these individuals," the American group said.

Some patients have experienced the symptom early on in COVID-19 illnesses, while others experience it further into the illness, according to Dr. James C. Denneny III, executive vice president and CEO of the American Academy of Otolaryngology – Head and Neck Surgery.

"The symptoms are clearly not as common as cough, fever and shortness of breath, but in the absence of a known cause for the smell disorder, this symptom may be an additional identifier for infected patients," he told USA TODAY in a statement.

'This virus just has the whole kit and caboodle':COVID-19 symptoms can be all or nothing

Noelle Ruiz, 27, first experienced a 101-degree fever, which subsided after about a day. Within six days, though, a headache and cough developed into more serious symptoms, with chest pain, extreme fatigue and the inability to catch her breath.

“I couldn’t really take a deep breath, I didn’t feel like I had enough air in my lungs,” she said.

But Ruiz had another set of symptoms: "I lost taste, food wasn’t appetizing, I couldn’t smell anything."

With the seasonal flu, patients can experience a cluster of symptoms as the illness begins, including a cough, fever, congestion, fatigue and loss of smell or taste, according to Dr. Gregory Levitin, an otolaryngologist at New York Eye and Ear Infirmary of Mount Sinai.

"What is most unusual about this new finding is that the loss of smell or taste was the only presenting symptom in a group of patients under the age of 40 who ultimately tested positive for the COVID-19 virus," Levitin wrote in an email to USA TODAY.

Rudy Gobert, the Utah Jazz center who tested positive for the coronavirus nearly two weeks ago, tweeted that he lost his sense of smell and taste, writing "haven’t been able to smell anything for the last four days."

According to Denneny and Levitin, damage to nerves in the naval cavity is believed to cause anosmia.

"It is unclear whether this is due to direct injury or swelling, but the symptom of anosmia from a viral illness is typically sudden and does not often respond to treatment with steroids or antiviral medications," Levitin added.

What does the coronavirus do to your body? Everything to know about the infection process

While losing smell or taste can affect a patient's quality of life, it can also be serious given that it impedes their ability to discern possibly dangerous odors, like gas leaks, he said.

Denneny said patients could recover their sense of smell fully, permanently lose it or land anywhere in between.

"While it is too early to determine how patients affected by COVID-19 will recover, given what we know it would be reasonable to hope that they would do as well as patients affected by the seasonal flu in years past," Levitin added.

Contributing: Elizabeth Weise

Follow USA TODAY's Ryan Miller on Twitter @RyanW_Miller