With cavitary tuberculosis, a cold and fever will not usually cause a relapse. However, if the treatment is not complete and the body’s immunity is low, it may cause a relapse. Colds are acute upper respiratory tract infections that usually do not cause a relapse of cured tuberculosis. However, if tuberculosis treatment is incomplete, residual Mycobacterium tuberculosis in the body may lead to relapse. TB is caused by Mycobacterium tuberculosis infection, which is highly resistant to dryness, cold, acid and alkali. At the same time, it is easy to develop drug resistance, and it may not be possible to completely eliminate Mycobacterium tuberculosis after treatment. After a cold or fever, the body’s resistance drops, and the Mycobacterium tuberculosis in the potential lesion reactivates and causes a recurrence of tuberculosis. Cavitary tuberculosis mostly has bronchial dissemination lesions. After effective chemotherapy, if some caseous tissue remains in the cavities, follow-up is still needed, even though sputum examination is negative for a long period of time.