The general opinion held by the medical profession at large has been that tuberculosis is disseminated chiefly by sputum, pus from tuberculous ulcers and sinuses, and from the dejecta of the bowel in persons or in animals suffering from tuberculous enteritis; these substances, from whatever source, becoming dry and later pulverized; they, together with their tubercle bacilli, are carried about by the currents of air. Such dust is commonly agitated by sweeping and dusting of carpets, rugs and furniture in rooms previously occupied by tuberculous patients. Indeed, the investigations of Cornet1 go far to corroborate this popular belief.
Cornet showed that dried sputum—dust—remained dangerous for months. He collected dust from the floors; walls and furniture of rooms previously occupied by persons suffering from pulmonary tuberculosis in various prisons, hospitals, asylums, and private dwellings, and, inoculating animals with such dusts, he determined the presence of virulent tubercle bacilli. Of the