Globally, tuberculosis remains a major public health problem, and despite scientific and technological advances and improved medical conditions, the road to prevention and treatment of tuberculosis is still tortuous. As one of the main means of preventing tuberculosis, BCG vaccination rate is quite high in many countries and regions around the world. However, the discussion about whether BCG can completely prevent tuberculosis has been the focus of medical community and public attention. This article will deeply analyze the protective effect and mechanism of BCG, reveal the complex relationship between BCG vaccination and the prevention of pulmonary tuberculosis, and the diversified strategies that should be adopted in the prevention and treatment of pulmonary tuberculosis. 
BCG, a live, attenuated tuberculosis vaccine, fights tuberculosis bacilli by activating the body's immune system. It enhances host resistance to Mycobacterium tuberculosis primarily by inducing a cellular immune response. However, the protective effect of BCG is not absolute, and its effectiveness varies among different populations, especially in **, where its ability to prevent ** tuberculosis is questioned. Although BCG is effective in preventing severe tuberculosis and tuberculous meningitis in children, it is not as effective in preventing tuberculosis as expected. This limitation may be related to a variety of factors, including the duration of immune protection after vaccination, geographic regional differences, and variation of tuberculosis strains. In addition, BCG vaccination cannot completely exclude the risk of tuberculosis infection, especially in high-incidence areas, where transmission remains a complex public health challenge. 
*Loading....In view of the limitations of the protective effect of BCG, other measures are needed to prevent and control tuberculosis. This includes improving living and sanitation conditions, strengthening early detection and** tuberculosis, and public health education. Especially in high-risk areas, regular TB screening and timely** are essential to control the spread of TB. With the deepening of medical research and the advancement of technology, the prevention and treatment strategies of pulmonary tuberculosis will be more diversified in the future. The research and development of new vaccines, more effective protocols and the application of personalized medicine will provide new possibilities for the prevention and treatment of tuberculosis. In addition, interdisciplinary research and international cooperation will also play an important role in the fight against tuberculosis and jointly address this global public health problem. 
*Loading....As one of the important means to prevent tuberculosis, the role of BCG vaccine cannot be ignored, but it should not be overly relied on. In the prevention and treatment of tuberculosis, a comprehensive strategy is needed, combining vaccination, public health measures and medical interventions to jointly build a multi-level protection network. Through continuous efforts and scientific methods, it is believed that human beings will eventually be able to effectively control and even eliminate tuberculosis, an ancient and stubborn disease.