Leptospirosis (leptospirosis for short) is an acute systemic infectious disease caused by various types of pathogenic Leptospira (Leptospira for short), and is a natural epidemic disease. Rodents and pigs are the two main sources of infection. Leptospirosis is common in almost all continents of the world, especially in tropical and subtropical areas. The disease has been found in 28 provinces, municipalities and autonomous regions in my country, and is most prevalent in the central and southern, southwestern and eastern China regions where rice is produced in abundance. The clinical characteristics are rapid onset, with early symptoms of leptospirosis such as high fever, body aches, weakness, conjunctival congestion, gastrocnemius tenderness, and superficial lymphadenopathy; in the middle stage, there may be pulmonary hemorrhage, diffuse pulmonary hemorrhage, myocarditis, hemolytic anemia, jaundice, systemic bleeding tendency, nephritis, meningitis, respiratory failure, heart failure and other target organ damage manifestations; in the late stage, most cases recover, and a few cases may have post-fever, uveitis, and cerebral artery occlusive inflammation, which are mostly related to post-infection allergic reactions. Diffuse pulmonary hemorrhage, myocarditis, hemolytic anemia, and liver and kidney failure are common causes of death.