1, Mycoplasma pneumoniae: is a smallest pathogenic microorganisms between viruses and bacteria, no cell wall, adhering to the respiratory mucosa, living in the cells, leading to cell necrosis, the release of a variety of inflammatory mediators, causing a series of tissue damage, in addition to respiratory infections can lead to many complications. For example: myocarditis, pericarditis, hepatitis, nephritis, meningitis, hemolytic anemia, thrombocytopenic purpura, myalgia, arthralgia, measles-like rash and other multi-system damage. 2.Transmission way: respiratory droplet transmission. 3, performance: light and light, with respiratory symptoms. Can be manifested as rhinitis, pharyngitis, bronchitis, pneumonia and so on. Pneumonia is characterized by fever, which lasts for more than 5 days. Dry cough at the beginning, gradually aggravated to paroxysmal irritating violent cough, heavy cough at night. Sputum is mostly white sputum, there may be bloody sputum, and there may be yellow sputum complicated by bacterial infection. Chest X-ray shows pneumonia, while lung auscultation is mostly without obvious wet woven grass 4. Diagnosis: Commonly used tests: anti-Mycoplasma pneumoniae antibody IGM titer increase >1:160 or more, or short-term progressive increase. Positive antibody characterization cannot be used as the basis for current infection. In pneumonia, chest X-ray shows flaky shadows in the lungs, and sometimes the shadows show wandering changes between the two lungs. 5, treatment: no cell wall, the characteristics of intracellular parasitism determines the penicillin and cephalosporin antibiotics are ineffective against it. Bacterial protein synthesis inhibitor drugs such as: macrolides, tetracyclines, quinolones can inhibit its growth. Only macrolides are suitable for children. Representative drugs are erythromycin and azithromycin. Depending on the condition the two drugs can be used alone or alternately. The course of treatment is not less than three weeks. Prognosis: This is a self-limiting disease and can be cured by itself. The severity of the disease and the duration of the disease varies greatly among individuals. It is closely related to whether the baby has underlying diseases. A small number of babies show multi-system damage, but there is no need to be alarmed, and most of the positive treatment has a good prognosis. The side effects of macrolide antibiotics are mainly gastrointestinal reactions, and long-term use can cause liver damage. Therefore, whether to use the drug needs to be considered comprehensively. Although the systematic treatment, there are still a few babies sputum or nasopharyngeal secretions can be separated to mycoplasma for several months, can lead to recurrence. 7, family care: maintain room temperature 18-20 ℃, humidity 60%, avoid too dry to facilitate sputum dilution. Light diet, pay attention to rest, avoid overwork. Keep indoor air circulation, avoid secondary infection.