COVID-19 generally refers to novel coronavirus infection, and novel coronavirus generally does not lose weight, so there is no need for excessive anxiety after novel coronavirus infection. Novel coronavirus infection may be due to the patient's low body resistance, or the virus invades the body due to improper wearing of masks. After being infected with novel coronavirus, the virus will invade the upper respiratory system, causing patients to have symptoms such as sore throat, dry cough, fever, fatigue and muscle aches.