Novel coronavirus is a respiratory virus, novel coronavirus pneumonia is highly contagious, the population is generally susceptible, the following three groups of people are more likely to be infected: 1, the elderly, and the elderly organs aging, immune system decline, and the elderly after infection with a higher rate of death; 2, people with underlying diseases, such as respiratory disease, hypertension, heart disease, diabetes, such groups of people infected with The new coronavirus infection can aggravate the original disease, but also can appear the new coronavirus pneumonia serious or critical illness; 3, the immune system is relatively low people, such as some diseases so that the patient’s immune function is damaged, and resistance is reduced, it is easy to infect the new coronavirus. In clinical work, if the above population is diagnosed with novel coronavirus pneumonia, doctors should pay high attention to reduce the possibility of progression to severe disease.