Tuberculosis is not contagious for more than half a year through standard treatment. In clinical practice, the main treatment for tuberculosis is to choose anti-tuberculosis drugs, and Mycobacterium tuberculosis is a contagious pathogen. The combination of isoniazid, rifampicin, ethambutol, pyrazinamide, streptomycin and levofloxacin against Mycobacterium tuberculosis is basically not infectious after more than two weeks of continuous use, and patients can live and work normally, and attention should be paid to regular follow-up. At this time, laboratory tests for Mycobacterium tuberculosis in sputum, and even culture of Mycobacterium tuberculosis in sputum are all negative, which is not infectious.