Demonstration of the poliomyeliticidal action of normal adult human serums1 has raised anew the question as to whether or not such adult immunities are due to previously unrecognized specific infections. The question is of more than academic interest. On its solution depends the interpretation of many epidemiologic data and the feasibility or desirability of many proposed quarantine and vaccination methods. Argu ments against previous subclinical infections as a cause of such adult immunities have been drawn from a study of Eskimo children. These isolated children apparently develop the same percentage immunity to diphtheria toxin as children in more crowded environments, diphtheria bacilli being practically unknown in arctic regions.
The most suggestive data, however, are those recently published by Friedberger, Bock and Fürstenheim2 of the Hygienic-Immunologic Institute, Berlin. These investigators studied the appearance in growing children of "antibodies" against such noninfectious agents as sheep and rabbit erythrocytes, antigens that
PANIMMUNITY. JAMA. 1931;96(10):775. doi:10.1001/jama.1931.02720360045012