What are the differences between the symptoms of influenza A and COVID-19?

　　Influenza A refers to type A influenza, and "new coronavirus" refers to infection with the novel coronavirus. Generally, there are differences between type A influenza and novel coronavirus infection in terms of fever severity and duration, characteristics of respiratory symptoms, systemic symptoms, the order in which symptoms appear, and manifestations of severe symptoms. Specific analyses are as follows:

　　1. Fever severity and duration: Patients with type A influenza typically have a sudden onset, and fever is usually high, reaching 39°C to 40°C. Patients infected with the novel coronavirus may experience varying degrees of fever, including low-grade, moderate, or high fever.

　　2. Characteristics of respiratory symptoms: Respiratory symptoms such as coughing, runny nose, and nasal congestion are more pronounced in patients with type A influenza. The cough is usually dry or accompanied by small amounts of white phlegm, and nasal discharge may be watery or slightly thickened and white, which may affect the patency of breathing. Coughing is also a common symptom of novel coronavirus infection, but a dry cough is more prominent, and some patients may experience severe coughing that lasts longer.

　　3. Differences in systemic symptoms: Systemic symptoms are more pronounced in type A influenza, mainly manifested as headache, muscle aches, and fatigue, which are more severe during the first few days after onset and gradually subside as the condition improves. Patients with novel coronavirus infection also experience systemic symptoms and may additionally develop diarrhea, which can last for several days.

　　4. Order of symptom appearance: In type A influenza, systemic symptoms such as high fever, headache, and muscle aches typically appear first, followed quickly by respiratory symptoms such as coughing, runny nose, and nasal congestion. In novel coronavirus infection, the order and combination of symptoms can vary; fever and cough may appear first, followed by reduced sense of smell or taste, or several symptoms may appear almost simultaneously.

　　5. Manifestations of severe illness: In rare cases, type A influenza may lead to severe pneumonia, characterized by rapid breathing, difficulty breathing, cyanosis of the lips, and potentially respiratory failure in severe cases. Patients with severe novel coronavirus infection may develop acute respiratory distress syndrome, manifested as severe breathing difficulties and hypoxemia, requiring mechanical ventilation to support respiration.

　　It is recommended that patients with type A influenza or novel coronavirus infection ensure adequate sleep, minimize physical activity, conserve energy, and aid in recovery.