[New methodological approaches to the use of the PHA reaction in determining anti-Shigella antibodies].

Pronounced correlation between the titers of hemagglutinating antibodies to different types of shigellae and other bacteria in healthy persons and in sick persons of control groups has been established. On the basis of this regularity a new approach to the use of the passive hemagglutination test in shigellosis, taking into account the ratio of antibody titers to different Shigella types, has been developed. This essentially increases the sensitivity and specificity of the test, thus making it possible to standardize its evaluation and permitting the effective diagnosis of shigellosis from the onset of the disease.