According to experimental data currently reported by Sabin and Duffy1 of the Children's Hospital, University of Cincinnati, dietary deficiencies in nursing mothers may retard the development of effective constitutional barriers against virus infections in nursing young, even though there is no retardation of normal growth or weight.
About four years ago it was shown by Olitsky and his co-workers2 of the Rockefeller Institute that in growing mice there is an acquired resistance to viruses not associated with the presence or absence of humoral antibodies. This was shown in its most striking form on injection of massive doses of the virus of vesicular stomatitis. In mice 2 weeks of age, injected intramuscularly, almost 100 per cent develop fatal paralyses. With 3 week mice there are 85 per cent of fatalities, decreasing to about 15 per cent of mortality by the fourth week. Mice over 6 weeks of age are