In 1985-1989 the etiological structure of acute bacterial meningitides (ABM) in children was studied in 4 largest industrial cities in different regions of the European part of the former USSR, as well as in 2 industrial cities of western Siberia. Due to the common methodological approach used in all investigations, comparable data were obtained in all cities. These investigations revealed that meningococci caused 53.0-86.7% of all cases of ABM in children, which corresponded to moderately increased morbidity rate in meningococcal infection (3.9-11.0 cases per 100,000 of the population, mostly 5.0-7.0 cases) in these cities with its progressive decrease during 3-4 years of observation. The gradual change of meningococci from group A, prevailing in the '70s and early '80s, to group B and in some cases the appearance of group C meningococci, accompanied by a decrease in morbidity rate, were noted. In St. Petersburg the indices of ABM morbidity in children aged up to 5 years for 1987 and 1988, caused by Haemophilus influenzae (0.74 and 4.13) and pneumococci (3.23 and 4.86), could be calculated. A great number of ABM cases of unclear etiology (15.9-33.3%) suggests that the number of ABM cases caused by these two infective agents was underestimated.

Acute Disease↗

PubMed1991

[Evaluation of the coagglutination reaction with urine in generalized forms of meningococcal infection].

The coagglutination test with concentrated urine was tried in 59 patients with validated generalized forms of meningococcal infection and in 23 ones with meningitides and pneumonia of a different etiology to assess the diagnostic value of this test. Positive results were obtained in 64.4% of the test group patient and in 4.3% of the reference patients (in a case with pneumococcal meningitis). The antigen serologic group in the urine coincided with the serologic group of the meningococcus that induced the disease in only 19 (50%) of the 38 patients in whom antigenuria+ was detected. In the rest cases urine samples reacted parallel with 2-7 antisera, in 5 patients with the antisera heterologic towards the serologic group of the meningococcus responsible for the disease. Antigenuria was observed between the second and ninth days of the illness, its peak was recorded on days 4-6. Repeated urine tests are more likely to yield positive results. The authors come to a conclusion that the test is simple and harmless for patients, but the presence of false positive results permits regarding it as but an auxiliary one.

Agglutination Tests↗

PubMed1991

[The adhesive activity of diphtheritic strains in relation to the characteristics of the infectious process they induce].

The degree of adhesiveness of 602 C. diphtheriae strains isolated from patients with different forms of diphtheria was studied on trypsinized sheep red blood cells (SRBC) used as an experimental model. The titer of bacterial suspension, i.e. its highest dilution ensuring the agglutination of 50% of SRBC, was assumed to be the index of adhesive activity. The toxigenic strains were more homogeneous with respect to the degree of their activity and proved to be moderately and highly adhesive, while among the nontoxigenic strains faintly and moderately adhesive ones prevailed. The degree of adhesiveness was not linked with the cultural biological strains variants, but depended on the form of C. diphtheriae infection. The toxigenic strains isolated from diphtheria patients were essentially more active than those isolated from carriers. Both toxigenic and nontoxigenic strains isolated in cases of prolonged carrier state (more than 4 weeks) did not differ in the degree of their adhesiveness and were essentially more active than the strains isolated from short-term carriers. The strains circulating in 10 closed groups with a high proportion of pronounced cases of carrier state (70.6% to 86.7%) were essentially more active than those circulating in 10 similar groups, but having a low proportion of pronounced cases of carrier state (6.7% to 23.8%). The conclusion was made that the degree of adhesiveness proved to be an important factor of C. diphtheriae pathogenicity, responsible for the formation of carrier state. Along with pathogenicity, this factor should be taken into consideration in the evaluation of the epidemiological importance of different sources of infection.

Agglutination Tests↗

PubMed1991

[The epidemiology of neonatal meningitis].

The epidemiological features of meningitides in newborns have been studied and criteria making it possible to distinguish the cases of intrauterine and postnatal infection have been proposed. The overwhelming majority of these infections has been found to occur due to hospital infections caused by enterobacteria and nonfermenting bacteria. In meningitides of this etiology the sources of infection are newborns colonized by these microorganisms. Infection is transmitted through everyday contacts through the hands of the medical staff. Besides, moist environmental objects serve as the additional reservoir of infection.

Enterobacteriaceae↗

PubMed1991

[The characteristics of Corynebacterium diphtheriae adhesins].

The study of the properties of C. diphtheriae adhesins revealed the absence of their thermostability, which suggested the protein nature of these adhesins. C. diphtheriae also showed pronounced mannose-resistant hemagglutinating activity, as this activity remained unchanged even in the presence of d-mannose. The comparison of the adhesive activity of C. diphtheriae with their phage and corycine sensitivity revealed essential differences between these macroorganisms in the degree of their adhesiveness. The phage lysability and corycine sensitivity of C. diphtheriae strains, determined by the properties of their surface structure, correlated with the degree of their activity.

Bacterial Adhesion↗

PubMed1991

[The antilysozyme activity of meningococci].

The antilysozyme activity of 184 meningococcal strains was studied. Such activity was found in all strains within the range 1-25 micrograms/ml, which was due to the heterogeneity of bacterial population. Strains varying in the total level of their lysozyme activity differed in the population structure by this sign. Preparations inhibiting antilysozyme activity could be differentiated according to the character of their action by the method of the population analysis. In the process of phagocytosis the selection of clones with a high level of antilysozyme activity was found to occur. The antilysozyme factor, heat resistant protein with a molecular weight of 10,000-30,000 D, was sensitive to trypsin.

Bacterial Proteins↗

PubMed1990

[The role of fibronectin in the pathogenesis of meningococcal infection].

We have characterized an interaction of 20 strains of Neisseria meningitidis serogroups A, B, C, 29E, W-135 and Z with immobilized fibronectin of human plasma. The adhesion of meningococci to fibronectin was determined by the extent of piliated cells and did not depend on the meningococcal serogroup. Binding of non-piliated or weakly piliated strains (2-5% of piliated cells in the stock) was sufficiently greater than those piliated (8-10%), where the adhesion to fibronectin was not at all observed. The examination of two well-piliated strains showed that the loss of pili resulted in the increase of bacterial adhesion to fibronectin. Constants of association and dissociation of piliated and non-piliated strains to fibronectin were calculated. The role of meningococci-fibronectin interaction in the pathogenesis of meningococcal infection is discussed.

Bacterial Adhesion↗

PubMed1989

[Meningococcal plasmids].

In Neisseria meningitidis strains isolated from patients with meningococcal infection and from carriers, the presence of plasmids has been detected by the modified method of H. C. Bernboim and J. Doly. The strains have been studied with respect to their pathogenicity and sensitivity to antibacterial substances. No correlation between the presence of plasmids and pathogenicity factors, such as antilysozyme activity, the presence of hyaluronidase and the positive reaction to Congo red, resistance to penicillin, serogroup and the sources of isolation, has been established.

Carrier State↗

PubMed1989

[Adhesion in meningococcus].

The adhesive activity of 113 meningococcal strains with different invasive properties and 10 Neisseria nonpathogenic strains have been studied. Adhesive properties have been revealed in 80-82% of these strains. Meningococcal strains isolated from the nasopharynx of carriers possess high hemagglutinating activity. The percentage of cells with pili in these strain was also higher than that in meningococcal strains isolated from the liquor of patients. This shows the presence of direct correlation between the number of pili in the cells (according to the data of electron microscopy) and their activity in the hemagglutination test, which makes it possible to use this test for the determination of the adhesive capacity of meningococci, associated with the presence of pili.

Animals↗

PubMed1989

[The initial stage of the infectious process--colonization and the means for its prevention].

Explore the source record for details and available documents.

Animals↗

PubMed1988

[Typing pneumococci using the coagglutination reaction].

Explore the source record for details and available documents.

Agglutination Tests↗

PubMed1988

[Preventive and therapeutic action of sera to the Re mutant of Salmonella minnesota in experimental generalized meningococcal infection].

The preparations of the blood plasma of humans and the sera of animals immunized with enterobacterial vaccine proved to have elevated titers of antibodies to deep determinants of the core of the gram-negative bacterial endotoxin molecule (to glycolipid of chemotype Re) and protected animals from infection with live cultures or serogroup A, B, or C meningococcal endotoxins. Sera from nonimmunized animals and normal donor blood plasma showed no protective activity. In experiments carried out on different models immune plasma possessed both a pronounced protective activity and a curative effect. The efficacy of protection depended not on the serogroup of the infective agent, but on the virulence of the strain used in the experiment, being statistically significant in all cases.

Animals↗

PubMed1988

[The role and place of serologic research in the system of epidemiologic surveillance of meningococcal infection].

The results of serological surveys, carried out with a view to the detection of capsular meningococcal polysaccharides in the passive hemagglutination (PHA) test and covering 1,289 patients with systemic meningococcal infection, 221 patients with bacteriologically confirmed meningococcal nasopharyngitis, 2,820 persons in organized groups of children and adults with different epidemiological situation (including 650 carriers) and 4,050 residents of 8 cities with different morbidity levels, were analyzed. The patients, the carriers and the members of organized groups underwent multiple surveys. As shown in this study, the confirmation of the meningococcal etiology of the systemic forms of meningococcal infection (meningitis, meningococcemia) in all cases with the exception of children under 1 year of age, as well as the determination of the groups of meningococci, could be achieved in the PHA test twice as frequently, i.e. in 60-70% of cases, as with the use of the bacteriological method. The same regularities were observed in nasopharyngitis. The conclusion was made on the possibility of using the PHA test for more exact determination of the group of meningococci, prevailing at the initial stage of diseases, this determination playing an essential role in the epidemiological surveillance. The data obtained as the result of serological surveys in organized groups may lead to conclusions on the circulation of meningococci and their group composition, thus showing the necessity of profound epidemiological study with ensuring epidemic-control measures. The selective serological study of some hundreds of donor sera is not expedient in big cities, as it provides no data on the circulation of meningococci there.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Bacterial↗

PubMed1987

[Antibody response to capsular polysaccharide antigen in an infection caused by meningococcus serogroup B in children].

The continuous synchronous cultivation of serogroup B meningococci and the use of the selected clones of producer strains has made it possible to obtain the serologically active preparation of the group-specific antigen from the culture in the exponential phase. The erythrocyte diagnosticum produced on the basis of this preparation has permitted the detection of group-specific antibodies in the sera of immunized rabbits and children with generalized infection caused by serogroup B meningococci. The intensity of immune response depends on the age of children. This new technique of the passive hemagglutination test is recommended for the confirmation of generalized infection caused by serogroup B meningococci.

Antibodies, Bacterial↗