Viral colds, customarily divided into viral and bacterial colds. Or common cold and influenza. Viral colds are: common cold, influenza and viral pharyngitis. Bacterial colds are: bacterial pharyngotonsillitis. The main difference is that the causative factors are different. Viral colds are due to viruses, while bacterial colds are due to bacteria. Influenza, is an acute respiratory infection caused by the influenza virus. The virus is present in the respiratory tract of the patient and is transmitted to others via droplets when the patient coughs or sneezes. Influenza is highly contagious, and because the virus is easily mutated, even a person who has had influenza will still be infected when the next influenza epidemic strikes, so influenza tends to cause outbreaks. Generally, there are more chances of epidemic in winter and spring, and 20-40% of people may be infected with influenza each time. The symptoms of simple influenza are: sudden chills, fever, headache, body aches, nasal congestion, runny nose, dry cough, chest pain, nausea, loss of appetite, and pneumonia or heart failure in infants, children or elderly people. Patients with the toxic form of influenza may have high fever, babbling, coma and convulsions, which can sometimes be fatal. Therefore, the disease can spread easily, so it should be isolated and treated early. The common cold, commonly known as influenza, is caused by rhinovirus, coronavirus and parainfluenza virus, which are present in the respiratory tract of patients and are transmitted to others via droplets. The common cold is much less contagious than the influenza, and people are generally susceptible to the disease only after getting cold, getting wet, or being overly tired because their resistance is reduced. Therefore, the common cold tends to appear individually, and rarely appears in batches, as in the case of influenza epidemic. When the common cold develops, most of the patients have low fever, rarely high fever, stuffy nose and runny nose, sore throat, headache, body aches, fatigue and weakness, the symptoms are milder than influenza, and there is no concern for life. 1. Viral flu is a common respiratory tract infection caused by a variety of viruses. Causes include cold, rain, overexertion, malnutrition, etc. 2.The main symptoms are sneezing, nasal congestion, runny nose, dry throat, sore throat, cough, hoarseness and other symptoms. Systemic manifestations include headache, body aches, fatigue, loss of appetite, or no fever, or low fever, or high fever, chills, etc. The course of the disease is usually 3 days to 7 days. 3. Transmission: The virus is spread into the air through sneezing, coughing and talking to infect others. Healthy people can also get infected with the virus by using the patient’s towel, washbasin or tableware. 4.Patients with cold and fever need to rest in bed, pay attention to keep warm and reduce activities. Ventilate the house frequently to maintain a certain temperature and humidity. 5, drink more boiled water, eat light and soft food. Second, clinical manifestations Viral flu is a non-infectious disease, seasonality is not obvious, patients generally do not have fever or moderate fever, no chills, few or no systemic symptoms, the course of 1-3 days, few complications such as otitis media, pneumonia and encephalitis. Influenza, on the other hand, is a category C infectious disease, with obvious seasonality, patients mostly have high fever 39°C-40°C, with chills, duration of illness 3-5 days, systemic symptoms are obvious, such as headache, generalized muscle pain, weakness, may have otitis media, pneumonia, encephalitis and other complications. Prevention Since there is no special treatment drug for cold, and once suffering from cold will have certain impact on work and life, so prevention is especially important. Enhance the resistance to prevent the invasion of pathogens is the key to prevention. The main measures are: 1, pay attention to exercise, reasonable arrangements for outdoor activities, to adapt to changes in the environment and climate. 2, clothing should be appropriate, with climate change should be timely increase or decrease, to prevent cold or overheating. 3.Control and treat chronic diseases and correct malnutrition. 4, pay attention to indoor ventilation, avoid going to crowded and dirty air public places. 5.Avoid overwork, drunkenness and other triggering factors. 6. Pay attention to personal hygiene and wash hands regularly.