Recurrences in Pneumococcus Pneumonia

A survey of the literature has failed to reveal any considerable body of data from which one may draw any conclusions regarding the actual immunity against reinfection that is conferred upon an individual as a result of an attack of pneumonia. It is of interest, therefore, to review certain features of a series of 57 cases with repeated attacks of pneumonia from which serologically identified pneumococci were obtained during each of 2 or more attacks.