In late April, the US Centers for Disease Control and Prevention updated its list of COVID-19 symptoms. The CDC initially listed fever, cough, and shortness of breath as the defining clinical aspects of COVID-19, but the agency now recognizes that repeated shaking with chills, muscle pain, headache, sore throat, and a loss of taste or smell may accompany an infection.
With the virus and clinical research moving at breakneck speed, researchers are observing more symptoms, with mounting evidence that the disease presents differently depending on the patient’s age.
A red or purple rash resembling frostbite or chilblains sometimes accompanies COVID-19 infection, particularly in younger and otherwise healthy adults. Other viral infections are known to provoke circulatory system inflammation that leads to similar skin lesions, and experts say this could be happening during COVID-19 infection.
Although difficulty breathing is an official symptom of COVID-19, many patients show exceedingly low blood oxygen levels without the accompanying breathlessness. Scientists are investigating why COVID-19 causes this unusual form of hypoxia.
Researchers in California, who published their study of 116 COVID-19 patients in the journal Gastroenterology in April, found 32 percent of people experienced mild gastrointestinal (GI) symptoms that included a loss of appetite, nausea, and diarrhea.