Chills, repeated shaking with chills, muscle pain, headache, sore throat and a loss of taste or smell.

Those are the six new symptoms the Centers for Disease Control and Prevention cautioned could be signs of the coronavirus.

The additions come as health experts' understanding of the confounding disease evolves. The CDC previously listed fever, cough and shortness of breath as symptoms.

Shortness of breath was tweaked to "shortness of breath or difficulty breathing" by the CDC.

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Coronavirus patients can experience a diversity of issues – from mild symptoms to severe illness. These symptoms generally appear 2-14 days after exposure to the virus. Patients may be most infectious in the days before they began showing symptoms, studies show.

The expanded CDC list is significant: Most testing sites require a patient to have a COVID-19 symptom before the individual can be tested.

The CDC recommends seeking "medical attention immediately" for trouble breathing, persistent pain or pressure on chest, bluish lips or face or a new "confusion or inability to arouse."

As COVID-19 has tightened its grip on the world in the past three months, medical comprehension of the virus has advanced. The World Health Organization and CDC first urged the public to be on the lookout for fever, dry cough and breathing difficulties.

Then came strange reports of people losing their sense of taste and smell. And there were sporadic cases of gastrointestinal issues, such as diarrhea.

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Another more recent phenomenon: purple or blue lesions on a patient’s feet and toes, most commonly appearing in children and young adults, dubbed “COVID toes.”

Though experts can’t pinpoint the condition, some hypothesized that it could be excess inflammation, a clotting of blood vessels or a thrombotic disorder known as purpura fulminans.

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Some doctors reported that the virus may trigger sudden strokes in adults in their 30s and 40s, which could be a result of blood clotting issues.

"The virus seems to be causing increased clotting in the large arteries, leading to severe stroke," Dr. Thomas Oxley told CNN.

"Our report shows a sevenfold increase in incidence of sudden stroke in young patients during the past two weeks. Most of these patients have no past medical history and were at home with either mild symptoms (or in two cases, no symptoms) of COVID," said Oxley, a neurosurgeon at Mount Sinai Health System in New York.

Contributing: Adrianna Rodriguez