New crown, or novel coronavirus pneumonia, is a class B infectious disease, but requires the prevention and control standards of a class A infectious disease to control the spread of the disease. Black Death is plague, and plague is a Class A infectious disease. The clinical symptoms and mortality rate of plague are more serious than those of novel coronavirus pneumonia, but the possibility of another global outbreak of plague is low, so it is not possible to simply compare the frightening degree of novel coronavirus pneumonia and plague.1. Infectiousness: novel coronavirus pneumonia is caused by novel coronavirus infection, and the virus is more infectious than bacteria, and novel coronavirus exists The new coronavirus has a variety of mutant strains and is mainly transmitted from person to person via the respiratory tract, making it more contagious. In addition, novel coronavirus pneumonia is more difficult to prevent and control than plague because there are a large number of patients with mild disease and asymptomatic infections, which are more insidious than plague and can easily lead to global epidemics. Plague is a virulent infectious disease, and the causative agent is Yersinia pestis. Naturally infected animals and patients with various types of plague can be used as the infectious source of plague, and its infectiousness is not limited to animals infecting people, but also spreads rapidly from person to person, but with the continuous improvement of plague prevention and control measures, the possibility of another large-scale outbreak is low. 2. There have been three pandemics in history, and the mortality rate of glandular plague is as high as 75% and that of pneumonic plague is as high as 100% if timely treatment is not available; 3. The prognosis is usually good if treated promptly and actively, but a few patients with severe disease can be life-threatening. Patients with plague may have high fever, chills, and confusion, and due to the proliferation of pathogenic bacteria in the blood, they may develop petechiae on the skin and mucous membranes, and their blood may turn black. With the continuous breakthrough of medical technology, the special drug for plague treatment has been identified as streptomycin, which can be combined with sulfonamides or tetracyclines at the same time for better treatment effect.