Influenza B is an influenza pandemic caused by influenza B virus infection. The onset of the disease is relatively rapid, causing a high fever of about 39-40°C. It is a highly dangerous respiratory infectious disease. The fever can last for about 4-5 days before it subsides. Initially, a high fever of 39°C or higher will occur and requires aggressive antipyretic treatment to avoid complications. When the fever is high, you can take ibuprofen extended-release tablets, or go to the hospital to inject drugs such as Chaihu injection, and you can put a fever-reducing patch on your forehead, and you can insert acetaminophen fever-reducing suppositories in your anus for fever-reducing treatment. It is also necessary to closely observe the mental state of the patient during the fever. If there are symptoms such as depression, indifferent expression, convulsions, vomiting, etc., you must go to the hospital internal medicine department in time. During fever, you should pay attention to ensure sufficient water intake, rest in bed as much as possible, and do not go to outdoor activities to avoid cross-infection. Avoid spicy and other stimulating foods, and ensure adequate diet and nutrition so as to help early recovery.