Wet rales are sounds produced by the rupture of blisters formed by gas passing through secretions such as exudate, sputum, blood, mucus and pus in the respiratory tract during inspiration, so they are also called blister sounds. Or it is thought to be the bursting sound produced by the wall of the small bronchus trapped and closed due to adhesion of secretions, which suddenly opens and re-inflates when inspiration is applied. Wet rales are one of the most important signs during auscultation of the lungs. The mechanism of formation is due to gas passing through the airway, if there are secretions (such as sputum, exudate, blood, mucus, pus, etc.) in the airway, blisters are formed and are produced when the blisters rupture. It is divided into coarse, medium and fine wet rales and twisted sounds. The distribution can be limited or both lung fields are full of wet rales. It is most commonly seen in bronchitis, pneumonia, bronchiectasis, pulmonary stasis, pulmonary edema, pulmonary infarction, intermittent alveolar dysplasia, etc. How should wet rales be prevented and treated? In March 1988, the World Health Organization (WHO) held a consultative meeting on pneumococcal vaccination in the elderly in Copenhagen and recommended that all elderly people and all high-risk groups should be vaccinated against pneumonia. Pneumonia vaccination is recommended for all elderly and all high-risk groups. The U.S. health goal for 2000 calls for a 60% or higher pneumococcal vaccination rate for high-risk groups at risk for pneumococcal infection, including those over 65 years of age. The pneumococcal vaccine can be given to those who are older or younger than 65 years old, but have cardiovascular or pulmonary diseases, diabetes, alcoholism, cirrhosis of the liver and immunosuppression (such as HIV infection, renal failure, organ transplant patients, etc.) The pneumococcal vaccine was approved by the Ministry of Health in China at the end of 1996 and is now widely used in health prevention departments throughout the country.