Use of immunoenzyme analysis in the rapid diagnosis and study of the characteristics of circulating O-antigen in biological fluids of patients with acute dysentery Sonne

The data on the clinical approval of the original enzyme immunoassay system for the determination of somatic O-antigen in the blood serum and urine of patients with acute Sonne dysentery are presented. The level of the antigen determined in the biological fluids of patients has been shown to depend on the severity of the disease. Different types of dynamic curves, reflecting the level of O-antigen in the biological fluids of patients with acute Sonne dysentery and characteristic of different clinical forms of the disease, have been established.     

Ways of determination of the intensity of the epidemic process in Shigella sonnei dysentery]

Proper view on the true prevalence of Sonne dysentery characterised by polymorphous clinical picture in which many cases coursed in subclinical form could be reached only by using additional active methods for detecting the infection rate of the population. For this purpose the authors applied passive hemagglutination test which permitted to reveal the response of the organism to the antigenic stimulation in the course of two months after the sustained sickness. Over 12 000 persons were examined. According to the results of passive hemagglutination test seasonal activization of the epidemic process occurred one month earlier than it was revealed by recording of the incidence of the disease. The results of the mentioned test also showed infection rate of the population with Sonne dysentery to be as a rule greater than established by the official statistics.     

Changes in the etiologic structure of Sonne shigellosis in its multiyear dynamics

The dynamics of Sonne dysentery morbidity in connection with changes in the structure of S. sonnei circulating among the population of Leningrad for the period of 1959-1984 was studied. Considering such sign as the leading fermentovar, three smaller periods were established in this stretch of time. Changes in the structure of circulating shigellae were accompanied by changes in the intensity and direction of tendencies or decrease in the manifest and asymptomatic forms of infection, as well as in annual morbidity levels and seasonal rises. A slow decrease in morbidity, which started in 1974, occurs in the presence of the predominant circulation of S. sonnei, fermentovar II, among the population; this fermentovar showed greater virulence and immunogenicity than other biovars. One of the decisive moments characterizing the dynamics of the epidemic process of Sonne dysentery is the intensity of the circulation of shigellae in the S-form, and the intensity of the population immunity of the host, linked with this fact, is subject to phasic fluctuations during each annual epidemic cycle.     

The manifestations of the epidemic process in shigellosis and their theoretical interpretation]

This work, based on the retrospective analysis of shigellosis morbidity among organized groups of adults, as well as the whole population of the city, demonstrates the manifestations of the epidemic process. Water supply was common in the city, while water consumption was autonomous. The organized groups of adults did not use the products of the local milk-processing factory. The following facts were established. The dynamics of morbidity in Flexner's dysentery showed the change of dominating variants of the infective agent, which reflected the action of internal mechanisms of the development of the epidemic process. The role of Sonne dysentery in the total structure of shigellosis morbidity did not correlate with the consumption of milk and milk products. The theory of the self-regulation of the parasitic system and the theory of correspondence served as the basis for the theoretical interpretation of the manifestations of the epidemic process of Shigella infections. To ascertain the real correspondence of individual Shigella species to concrete transmission factors, further investigation are necessary.     

Experience with the diagnosis of dysentery in adults by determining antibodies to Shigella in the saliva]

Concentration of immunoglobulins and titres of antibodies to Sh. sonnei, Sh. flexneri and enteropathogenic E. coli 0111 was determined in mixed saliva and the blood serum of patients suffering from Sonne dysentery, acute intestinal diseases of unknown etiology, and healthy individuals. The sum total immunoglobulin concentration in mixed saliva proved to be 53--81 times less than in the blood serum, but in the first substrate there was 53--75, and in the second--15% of immunoglobulin A. There proved to be distinct changes in the specific IgA-antibodies in the saliva of patients with Sonne dysentery. A preponderant accumulation of IgG-antibodies was noted in the blood serum. Elevation of both types of antibodies was maximal during the second week of the disease. Sonne dysentery was diagnosed in 80% of the patients by recording the intensity of shifts in the specific antibodies in the saliva, and in 63%--in the blood. The expediency of immunological testing of saliva for the diagnosis of dysentery is substantiated.     

A method for determining specific circulating immune complexes in patients with acute Sonne dysentery]

The antigen-specific method for the determination of specific immune complexes in the blood serum of patients with acute Sonne dysentery has been developed on the basis of the enzyme-linked immunosorbent assay with the use of reagents manufactured in the USSR. The possibility of the early prognostication of prolonged carrier state by using the proposed method for the determination of the level of specific circulating immune complexes has been shown.     

Etiologic structure of bacterial dysentery in the USSR in 1983-1985

The etiological structure of dysentery in the USSR in 1983-1985 is characterized. Sonne dysentery was found to prevail in the territories with adequate water supply, while dysentery caused by Shigella flexneri prevailed at the territories with unsatisfactory water supply. S. dysenteriae and S. boydii were found to play a limited role in the etiology of dysentery. In the presence of global pandemic, an increase in the isolation rate of S. dysenteriae I in the USSR is observed. The data on the biochemical structure of S. sonnei are presented.     

Population migrations and the epidemic process of Flexner and Sonne dysentery

Analysis of the materials from the Khabarovsk Territory for the representative period of 25 years (1956-1980) revealed the influence of the migration of the population on the level and dynamics of morbidity in different kinds of dysentery, Flexner's dysentery shown to occur more frequently than Sonne dysentery. Intensive migrations increase the proportion of susceptible persons among the population, thus facilitating the formation and circulation of Shigella strains with pronounced virulence.     

Conditions and factors determining the etiological structure of dysentery and its changes. Report 1. Epidemiological theory of etiological selectivity of the main (primary) pathways of infection and their differences in various nosological forms of dysentery]

The authors present the elaborated and formed epidemiological theory ("conformity theory") according to which the etiological structure of dysentery is determined by the etiological selectivity of the main (primary) waves of transmission of the infection differing in various nosological forms of dysentery. In Grigoriev-Shiga dysentery the domestic way of the spread of infection plays the main role, in Flexner and Newcastle dysentery--the water way, and in Sonne dysentery--the food way (particularly through the milk). Evolution of the etiological structure of dysentery serves as the reflection of evolution of the principal ways of transmission. The complex of prophylactic and antiepidemic measures in individual noslogical forms of dysentery should be differentiated and be directed in epidemiological sense to the neutralization of the corresponding main (primary) way of transmission of the infection.     

Enterotoxic activity of live cultures of Sonne dysentery microbes and formation of enterotoxin in vivo]

The great majority of virulent Sonne dysentery bacillus cultures caused an accumulation of the fluid in the lumen of the isolated segment of the rabbit small intestine containing a great amount of mucus and sometimes of the blood as well; the segment mucosa was hyperemic and had punctate hemorrhages. Avirulent microbial cultures as a rule caused no exudation in the intestinal lumen. Sterile and concentrated contents of the intestinal loops responding to the centrated contents of the intestinal loops responding to the administration of the virulent culture of Sonne bacillus or a toxigenic strain of Grigoriev-Shiga dysentery bacillus caused a positive response in other rabbits. The character of the exudate and the changes in the mucosa failed to differ from such following the administration of live cultures.     

Trial of the toxins of the Sonne microbe and cholera vibrio in an isolated loop of mouse small intestine]

Enterotoxic properties of neuro-and endotoxins of Sonne dysentery bacillus, of cholerogen, and Bowen's cholera vibrio endotoxin were determined on a model of an isolated loop of the mouse small intestine. In definite doses all the mentioned preparations could induce dilatation of the isolated loop of the mouse small intestine. In case of Sonne bacillus neurotoxin this property correlated with the toxicity of the preparation for the animals and failed to depend on the virulence and biochemical reference of the strain from which it was obtained. Marked variations in the sensitivity of mongrel and linear mice to the mentioned preparations were noted.     

Reactogenicity and immunologic activity of live enteric Sonne dysentery vaccine from a spontaneous mutant]

Live dysentery Sonne vaccine from a spontaneous mutant proved to be practically areactogenic and specifically harmless in oral immunization of children aged from 7 to 13 years, in doses of from 3 to 25 milliard live microbial cells and in single and triple immunization schemes. Weak reactions of the gastro-intestinal tract were noted with the same frequency (1.7%) in children immunized with the vaccine and in children given placebo (2.2%). There proved to be a significant increase in the serum of the immunized persons of the level of specific hemagglutinins, and also of the IgA-and IgM-titers in 82% of the persons vaccinated; they persisted at a high level for 2 months. The appearance of IgA-antibodies in high titres in the persons vaccinated orally pointed to a marked local and general immunological activity of the live dysentery Sonne vaccine from the spontaneous mutant processing the capacity to survive in the intestine of children for a long time.     

Immunoglobulin and antibody content in the blood serum, coprofiltrate and saliva of patients with Sonne dysentery]

The authors studied the immunoglobulin and specific antibodies content of various classes in the serum, coprofiltrates and the saliva of 68 patients suffering from Sonne dysentery and in 48 healthy adult persons. Mancini's test demonstrated a significant elevation of IgG and IgM content in the blood of dysentery patients in comparison with that in healthy persons, and the absence of any changes in the IgA content. The titres of specific IgG-, IgA- and IgM-antibodies in determination in the modified Coombs' test increased consideerably during dysentery infection and were found in high titres during the first week of the disease; they reached the maximum during the second week and persisted at this level for 3 weeks. The greatest antibody elevation was in the IgA-class. Antibodies revealed in the coprofiltrates and the saliva of dysentery patients belonged to IgA- and IgG-class. There proved to be a correlation of the antibody changes in these two secretions.     

Shigellosis in the USSR: the biochemical picture of Shigella sonnei

The article deals with original data characterizing the biochemical picture of S. sonnei circulating in the USSR in 1983-1985. Sub-biovars IIe, IIg and Ia have been shown to prevail practically in all regions, irrespective of the intensity of functioning of the centralized alimentary and chronic water routes of transmission of shigellae. These sub-biovars most frequently cause significant alimentary outbreaks of Sonne dysentery transmitted with milk. Doubts are expressed concerning the importance of the immunological factor in the formation of the biochemical picture of S. sonnei. The necessity of the additional differentiation of strains belonging to the prevalent sub-biovars for epidemiological purposes is emphasized.     

Method for the short-term prognosis of annual morbidity indices in Sonne-type dysentery

A method for making the short-term prognosis of the annual morbidity rate in Sonne dysentery, both total and among individual groups of population, is presented. The preliminary prognosis is based on the expected data on meteorological factors, supplied by the weather forecast service, and the final prognosis, on the actual prognostic factors for June-July of the current (prognosed) year.     

The formulation of epidemiological hypotheses by using the methods of multivariate statistical analysis

The work demonstrates the main approaches to the use of the methods of multidimensional analysis for the creation of a hypothesis on the mechanism of the epidemiological process of dysentery in organized groups. The main risk factors have been established, and their role in the formation of annual, all-the-year-round and seasonal dysentery morbidity has been quantitatively evaluated. The results of analysis show the existence of diverse variants of the alimentary route of the transmission of infection, maintaining the epidemic process of dysentery, and the necessity of differentiating measures for the prophylaxis of all-the-year-round and seasonal morbidity.     

An analysis of the dysentery epidemic process in Blagoveshchensk

The retrospective analysis of dysentery morbidity in Blagoveshchensk for the period of 1960-1987 was made. The regularities linking general natural and biological factors triggering the epidemic process with dysentery morbidity among the population are emphasized. The study revealed that under the conditions of Blagoveshchensk dairy products were of major epidemic importance among factors contributing to the transmission of dysentery. Such a factor as flies also had a definite influence on the epidemic process of dysentery. Another risk factor was drinking water which influenced the epidemic process both directly and indirectly through dairy products and, probably, other foodstuffs. Reliable correlation between dysentery morbidity among the population and the quality of dairy products, tap water and the number of flies was established.     

Manifestations of the cyclic nature of the epidemic process in dysentery

Different forms of dysentery, especially those caused by Sh. sonnei and Sh. flexneri, have been found to differ considerably in their cyclic recurrence. The development cycles of the epidemic processes of dysentery have an objective character, occur in the presence of any tendencies in the morbidity rate, and depend on the natural factors. Thus, the cycles of increase and decrease in morbidity are 3, 6, 9, 12 years for dysentery caused by Sh. sonnei and 6, 7, 8 years for dysentery caused by Sh. flexneri.     

Serological method of detecting the antigens of the causative agent of Sonne dysentery in lysates of the fecal inoculates from patients]

Serological method of detection of Sh. sonnei antigens in the lysates of the patients, fecal cultures is suggested and approved. In the majority of cases of the results of bacteriological and serological methods of study of the feces coincided. Data confirming the specificity of the antibody neutralization test (ANT) in Sonne dysentery are presented. In connection with detection of the screening action of the Vi-antigen of typhoid bacilli there were elaborated additional methods for verifying the specificity of the ANT results. It is recommended to keep agar plates after selection of suspicious colonies during the bacteriological test; the lysate of the microbial crop should be additionally subjected to the ANT, this considerably increasing the percentage of laboratory confirmations of dysentery caused by Sh. sonnei.     

Patterns determining the dynamics of the epidemic process in Sonne dysentery and its relation to the type of causative agent]

The results of studying the dynamics of the epidemic process of dysentery, based on the data from 3 districts of Moscow, are presented. The study revealed the periodicity of 3 years in the course of the epidemic process of dysentery, occurring against the background of a considerable predominance of Sh. sonnei, biochemical type 2. The use of the cohort method for analyzing the age structure of dysentery cases showed the possibility of using this method to find out to what extent the epidemic process repeatedly affected the same groups of population.