Application of the Neufeld Reaction to the Identification of Types of Pneumococci —With the Use of Antisera for Thirty-Two Types

Abstract
The Neufeld reaction using homologous type-specific antisera (rabbit) is specific for all known types of pneumococci, I-XXXII. All Type III antisera should be tested for cross-reactions with Type VIII since some will produce cross-reactions with the latter type. Preliminary tests with combinations of several antisera are helpful in determining the type of pneumococcus present. Success often depends on the use of a relatively very small proportion of the material to be tested to a relatively large proportion of antiserum. Detailed directions are given for preparing specific anti-sera.