Plague is a virulent infectious disease caused by Yersinia pestis, commonly known as the “Black Death”, and is one of the international quarantine infections. In the face of the sudden outbreak of the plague epidemic, people are panicking and at the same time expressing great concern about the plague, which was once synonymous with the plague: What kind of infectious disease is this ancient disease? What are the ways of transmission? How to prevent and control it scientifically? Yersinia pestis is a short, ovoid, gram-positive bacillus. It is resistant to cold and moisture and can survive at -30°C, but is not very resistant to general disinfectants. Boiling for 1-2 minutes or sunlight exposure for 4-5 hours can kill the bacteria. Rat flea bites are the main way to contract plague Because plague is highly contagious and has a high mortality rate, the Ministry of Health in China listed it as the top of Class A virulent infectious diseases in the Prevention and Control of Infectious Diseases Law promulgated in China. Wild rats, gophers and dry otters are important infectious sources of inter-rodent plague, and brown house mice, yellow-breasted rats, black house mice, dry otters and long-clawed rats are important infectious sources of human plague. The bite of rodent fleas is the main way of plague infection in humans. Yersinia pestis proliferates in the stomach of a flea after it bites the blood of a sick rat. When the fleas bite the human body and suck the blood, the germs in the flea’s stomach are imported into the human body and cause the disease to develop. Yersinia pestis in the sputum of pneumonic plague patients can also be spread by droplets through breathing, talking, coughing, etc., causing pandemic disease. A few can be infected through direct contact with the patient’s sputum, pus, or the skin, blood, or flesh of a germ-bearing otter via broken skin. There are three main clinical types of Yersinia pestis infection in humans, and the following types of manifestations can occur: (1) Glandular plague: the most common, mainly manifesting as enlarged lymph nodes with redness, swelling, heat and pain in the surrounding tissues. If not treated in time, it can develop into sepsis, severe toxemia, etc. (2) Pneumonic plague: The condition is dangerous and the death rate is high. The onset of the disease is rapid, with body temperature reaching 39-41℃, shortness of breath within 36 hours of onset, violent cough, and coughing up large amounts of foamy blood sputum or bright red sputum. If treatment is not timely, most of them die within 2-3 days due to heart failure, hemorrhage and shock. The current plague outbreak in Qinghai is pneumonic plague. (3) Septicemic plague: The condition is the most dangerous. The main manifestations are high fever, extensive skin bleeding, petechiae, bruising, and confusion. Most of them die within 24 hours after the onset of the disease, and the disease death rate is very high. Other diseases such as skin plague, intestinal plague and meningeal plague are relatively rare. Although plague is dangerous, it is a disease that can be cured with specific drugs. Commonly used drugs include streptomycin, gentamycin, tetracycline and chloramphenicol. Clinical practice has shown that streptomycin has a very good therapeutic effect on plague, and the cure rate has reached 97%-100%. In recent years, some doctors have used cephalosporin antibiotics to treat plague with good results. To prevent plague, comprehensive measures should be taken to exterminate rats and fleas, prevent plague among animals, and strictly isolate plague cases. Personnel entering the infected area must wear protective clothing, masks, protective goggles and gloves. People in and around the plague area and medical personnel entering the infected area should enter the infected area only after 10 days of plague vaccination. Antibodies are generally produced 10 days after vaccination and the immunization period is 1 year, with a booster vaccination required once a year. The threat still exists After the 3rd world pandemic of plague, plague cases were maintained at a low level. Since the 1990s, the number of plague cases has been on the rise. Currently, there are regional epidemics of plague around the world, with more than 2,000 cases of plague reported each year. Since the 1950s, China has been carrying out large-scale eradication and control of infected areas, and the plague epidemic is basically under control, but this does not completely exclude the threat of plague to us. There are 11 plague-stricken areas in China, most of which are located in the northwest and southwest, especially in the border areas such as Qinghai, Tibet and Xinjiang. However, we believe that the incidence of plague can definitely be reduced as long as we strengthen the monitoring of plague source areas and take active and effective prevention and control measures, while individuals maintain a healthy lifestyle.