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[Detection of the etiologic structure of generalized and localized forms of meningococcal infection using the passive
Abstract:
Preparations of formalin-treated erythrocytes sensitized with meningococcus polysaccharides of serological groups A, C, X, Y, and Z were used for the purpose of examination of patients with meningococcus infection; these preparations were highly specific in the tests of precipitation, hemagglutination and hemagglutination inhibition. Indirect hemagglutination test with the sera of 99 patients suffering from generalized forms of meningococcus infection was conducted with the mentioned preparations in Moscow and Novosibirsk in 1974--1975 when a stable morbidity decline was noted in these towns after an epidemic rise. The diagnostic value of this test was confirmed: it permitted to diagnose meningococcus etiology beginning from the 5th day of the disease and to decipher it from the aspect of individual serological groups. As shown, the incidence of cases caused by serological group A, reaching 87% at the height of the epidemic rise, fell to 49.5% at the stage of decline. Cases caused by group Y which was not encountered formerly were revealed in 16.2% of the patients. Among 127 patients with miningitis of nonmeningococcus etiology meningococcus antibodies to groups A and Y were revealed with the same frequency (in titres of not over 1 : 20--1 : 80), but the leading role of serological group A in the etiology of the manifest forms permitted to draw a conclusion on the presence of a higher invasiveness in the strains of group A.
Insights
The indirect hemagglutination test effectively diagnoses meningococcus infections, identifying specific serological groups like A and Y. This method aids in understanding disease etiology and strain invasiveness.
Area of Science:
- Microbiology
- Immunology
- Epidemiology
Background:
- Meningococcus infections pose significant public health challenges.
- Accurate and timely diagnosis is crucial for effective patient management and disease control.
Purpose of the Study:
- To evaluate the diagnostic utility of formalin-treated erythrocytes sensitized with meningococcus polysaccharides for identifying infection etiology.
- To determine the prevalence of different meningococcus serological groups during epidemic decline.
Main Methods:
- Preparation of formalin-treated erythrocytes sensitized with specific meningococcus polysaccharides (groups A, C, X, Y, Z).
- Application of indirect hemagglutination (IHA) tests using sera from patients with generalized meningococcus infection.
- Comparison of antibody titers in patients with meningococcus and non-meningococcus meningitis.
Main Results:
- The IHA test demonstrated high specificity and diagnostic value, enabling diagnosis from the 5th day of illness.
- Prevalence of serological group A decreased from 87% during epidemic peak to 49.5% during decline.
- Serological group Y, previously unencountered, was identified in 16.2% of patients.
Conclusions:
- The IHA test is a reliable method for diagnosing meningococcus infections and serotyping strains.
- Shifts in serogroup prevalence (e.g., emergence of group Y) were observed during epidemic decline.
- Serological group A strains exhibited higher invasiveness in manifest forms of the disease.