Does tuberculosis infection without symptoms spread from one person to another ? when does tuberculosis infection start spreading ?

Tuberculosis is generally spread when a person has a lung lesion and is coughing. If the person is under treatment and no tubercle bacilli are detectable in the sputum, the person does not spread TB.

Most people with TB have lung infection which makes them cough, which can start within a few weeks of becoming infected, but is most common when TB reactivates months or years later. Even if you are around someone with TB who is not coughing due to lung infection, you are not at risk. Transmission of TB by persons without symptoms is rare if it occurs at all.

Tuberculosis generally does not spread without symptoms, usually a chronic cough. Spread without coughing is very rare.