This chapter discusses the possibilities of infection of nurses and other attendants in the institutional treatment of phthisis, and the possibilities of infection of doctors who attend consumptive patients at their homes or in institutions. The most carefully investigated experiences are those of the Brompton Hospital and of the Victoria Park Hospital for Diseases of the Chest, the former investigated by Drs. Cotton and Theodore Williams, the latter by Dr. Andrew. The danger of infection becomes especially great when healthy people have to sleep in the same rooms with sick people, and even, as unfortunately still frequently happens among the poor, in the same bed. This kind of infection has struck attentive observers as so important that tuberculosis has been frankly and justly called a dwelling disease. It will be observed that death-rate from influenza is excessive, and the comparison is interesting, illustrating as it does the much more rapid and more intense infectivity of the latter disease.