The immunoglobulin response to reimmunization with rubella vaccine.

An adolescent military dependent population, 86% of whom had documented history of rubella immunization, was screened by two commercially available rubella hemagglutination inhibition tests. All those who were R-HAI antibody negative were immunized, and postvaccination sera were examined for the development of rubella-specific antibody (R-IgM). R-IgM was not found in any of the previously immunized subjects despite the lack of R-HAI antibody. R-IgM was detected in two seronegative subjects who had no documentation of previous rubella immunization. Thus, although the R-HAI antibody had waned, the engrams of previous immunization remained, resulting in a secondary response on re-exposure. The development of a secondary immune response, despite the absence of detectable r-HAI antibody, casts doubt on the validity of R-HAI as a screening test to determine rubella immunity. The data support continuing mass immunization of preschool children and vaccination of all older females who lack documentation of rubella immunization.

Detection of bacterial antigen in pleural fluid by counterimmunoelectrophoresis.

Pleural fluid specimens from 87 patients were studied using counterimmunoelectrophoresis with pneumococcal, staphylococcal, and Hemophilus influenza b antisera. This method compared favorably with traditional bacteriologic methods and in addition provided a presumptive etiologic diagnosis in more than half of the specimens with negative bacterial cultures. One cross-reaction between H. influenza b antiserum and a pleural fluid specimen with an Escherichia coli isolate was observed.