Immunity to Influenza as Related to Antibody Levels

Abstract

IN studies of naturally acquired and experimentally induced influenza it has been found that disease occurs in persons with moderate or high serum levels of neutralizing antibody directed against the infecting influenza virus whereas others with low titers of such antibody may escape infection.1 2 3 4 5 6 A search for an explanation for this apparent immunologic paradox has been the principal aim of this investigation. In the present study the circumstances alluded to above were reproduced. Subjects with substantial titers of antibody to 3 different influenza strains, including that used for live-virus challenge, were among those who became ill after challenge, and those . . .