Sub-intimate contacts who touch the clothing of a TB patient are generally not infected.
Tuberculosis is transmitted mainly through respiratory droplets, and patients with open tuberculosis are the main source of infection.
When a TB patient with tubercle bacilli in sputum coughs, coughs up sputum, sneezes, spits, the tubercle bacilli in the lung lesions can appear in the air with the droplets formed by respiratory secretions, and if a healthy person who happens to be in the same space inhales the droplets with tubercle bacilli, he or she is susceptible to infection.
Mycobacterium tuberculosis leaves the human body and survives for only a few hours in the outdoor environment, and contact with a person who touches the clothing of a person with tuberculosis in the next closest contact does not generally lead to infection.
Therefore, patients with open TB need to be isolated from the respiratory tract, and if they have symptoms of discomfort such as low-grade fever and cough, they should seek medical attention to find out the cause.