Serologic Studies of Meningococcal Infection and Polysaccharide Vaccination

Abstract

Patients with meningococcal infection and volunteers who received meningococcal polysaccharide vaccines were studied by a variety of assays for antibody to compare the sensitivity and specificity of the tests. Indirect hemagglutination, using human erythrocytes sensitized with antigens of purified polysaccharide, was found to be highly sensitive and serogroup specific in demonstrating antibody response to natural infection and vaccination. Complement fixation using an antigen of protein was sensitive for detecting infection but did not show antibody response to polysaccharide vaccination. An immunofluorescent assay using whole organisms was shown to be sensitive and cross reactive for species following natural infection but group specific following immunization. Precipitation of polysaccharide in a micro-Ouchterlony system was a relatively insensitive test. None of these serologic assays have been evaluated as measures of the immune status of individuals or populations. For this purpose only the test for bactericidal activity of serum has been shown to have predictive value.