The BCG vaccine is primarily designed to prevent tuberculosis. BCG is an attenuated live vaccine, a live bacterial vaccine made from attenuated bovine tuberculosis mycobacterium suspension, after vaccination, it can enhance macrophage activity and strengthen the ability of macrophages to kill tumors, belongs to the first class of vaccine of China’s immunization program, and is provided by the government free of charge for vaccination. BCG vaccine generally within 24 hours after the birth of newborns need to be inoculated with the first injection, after inoculation may form small local ulcers, be careful to protect the inoculation site. After BCG vaccination, it will cause the body to produce a specific immunity to Mycobacterium tuberculosis, which can prevent the germs from reproducing and spreading in the body, thus preventing tuberculosis diseases such as tuberculosis and tuberculous meningitis.