Tuberculosis (TB) is not spread by sharing dishes, drinks, food or clothes or touching surfaces. TB bacteria are released into the air when a person with TB disease of the lungs speaks, coughs, sneezes or sings. Other persons staying in the same indoor environment (e.g. same room or flat) may get bacteria in their lungs when they breathe in this air and get infected. After the sick person leaves the room, TB bacteria will remain in the room air for hours, especially in small places with poor ventilation. If the sick person has left the room many hours ago or the room has been ventilated, there is no risk of TB for the person cleaning the room.