Influenza (influenza) is an acute respiratory infection caused by the influenza virus and is a highly contagious and fast-spreading disease. Suggestions: It is mainly spread through airborne droplets, person-to-person contact or contact with contaminated objects. The typical clinical symptoms are: acute onset of high fever, generalized pain, significant malaise and mild respiratory symptoms. The fall and winter seasons are usually its high season, and the complications and deaths caused are very serious. The disease is caused by the influenza virus, which belongs to the family of orthomyxoviridae and is 80-120 nm in diameter, spherical or filiform. Influenza virus can be divided into A (A), B (B), C (C) three types, A virus often occur antigenic mutation, infectious, rapid transmission, prone to widespread epidemics. Symptoms: 1. Rapid onset, chills, fever, body temperature peaks within a few hours to 24 hours, 39-40 ℃ or even higher. With headache, generalized aches and pains, fatigue, loss of appetite. Respiratory symptoms are mild, dry throat, dry cough, diarrhea may be present. 2. Facial flushing: conjunctival outer canthus congestion, pharyngeal congestion, follicles on the soft palate. Influenza and cold flu and influenza are both caused by viral infections. Since the virus is airborne, the first to bear the brunt is the nose. The virus first infects the nasal mucosa and then multiplies, resulting in inflammation of the nasal mucosa and symptoms such as sneezing, runny nose and nasal congestion. A common cold is a “nasal cold” and its effect on the body is usually limited to the respiratory system. All symptoms are related to the nose, such as runny nose, stuffy nose and sore throat, cough, and even fever. It usually clears up in a few days. Influenza is caused by the influenza virus. Influenza symptoms affect the whole body, including fever and chills, sweating, body aches, headache, bone pain, muscle pain, fatigue, loss of appetite, cough, nasal congestion, etc. In severe cases, pneumonia and other complications can be fatal. Influenza viruses are characterized by a variety of types, and new varieties of viruses emerge every decade or so.