Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: heredity of tuberculosis and of syphilis. A second possibility is that the predisposition to a given infection is inherited by the child from its parents. This aspect of the subject also will be more fully discussed in the chapter on Tuberculosis, with relation to which alone it is of material importance. Intrauterine infection of the fetus in the course of acute infectious disease in the mother has been observed repeatedly. A number of cases are on record in which children have been born with the eruption of smallpox or with pneumonia. As the result of numerous experimental inquiries upon this subject—through the infection of pregnant animals—it may be accepted that the healthy placenta constitutes a dense filter, which permits the passage only of the toxins, but never of the bacteria, circulating in the blood of the mother. Living disease-germs can pass over to the fetus only when a lesion of the placentais induced through slight hemorrhages or in some other way. More common than intrauterine infection is infection during birth, of which the blennorrhea of the new-born is a conspicuous example. m. IMMUNITY, IMMUNIZATION, AND CURE. Immunity is the insusceptibility to an infectious disease, the slighter tendency of an organism, or the complete impossibility, to be attacked by this disease. This property may be congenital in animals and man as natural immunity. Our domestic animals are never attacked by the acute exanthemata so widely disseminated among human beings ; and birds under natural conditions never suffer from anthrax, which is not at all uncommon among cattle. In the severest epidemics of cholera a large number of persons escape the disease, including even some living under the most unhygienic conditions and without any special precautionary measures, while thos... --This text refers to an alternate Paperback edition.