A sudden loss of smell and taste could be a sign of mild coronavirus disease. Covid-19 symptoms include fever, dry cough, tiredness, shortness of breath or difficulty breathing. Those with a sudden loss of smell must home-quarantine and get tested for coronavirus disease. Very few conditions lead to sudden amnosia, or the loss of smell and taste. It should be treated as a sign of coronavirus disease, especially by people who risk exposure at the frontlines, such as health workers. People with a sudden loss of smell are 10 times more likely to have Covid-19 than any other infection, according to a study by the University of California in San Diego. The effect was temporary and patients recovered taste and smell within a few weeks of infection.