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The paper provides the analysis of the prevalence rates of tuberculosis among children and adolescents in the Russian Federation, which has been made on the basis of the data available in official reporting forms Nos. 8, 33 (approved by the Resolution of the Russian Statistics Agency on November 11, 2005), and 47 (approved by Resolution No. 175 of the Russian Statistics Agency on September 10, 2002). Correlations between epidemiological indices have been calculated and assessed. The age-related features of the occurrence and course of tuberculosis have been studied among various age groups of children. It is concluded that in this situation in order to improve the epidemic situation among children and adolescents, emphasis should be primarily placed on the activation of intersectoral interaction of primary health care and tuberculosis service: to actively attract general practitioners, local pediatricians and therapists to prophylaxis in children.

The paper shows how a tuberculosis monitoring system is under development at the level of the Russian Federation subject--the Belgorod Region. The tuberculosis monitoring system allows an effective control of both tuberculosis-controlling measures determined by the existing normative documents and orders and supplementary measures to enhance the effectiveness of tuberculosis control in the region. Tuberculosis monitoring should be further improved at the regional region by the sections: outpatient visit, antiepidemic measures in the foci; children's sanatorium work, cohorts to be examined by a physio pediatrician.

The paper analyzes whether it is possible to predict a risk for postoperative empyema, by studying a totality of characteristics of a patient, a pathological process, and the properties of MBT in 46 patients with progressive fibrocavernous tuberculosis. It also shows it actual to accomplish this task with a prediction accuracy of 89.5-100%, by simultaneously taking into account both the bacteriological properties of MBT (the magnitude of Mycobacterium tuberculosis excretion and viability) and different combinations of serum biological parameters that reflect the activity of an inflammatory process.

The paper presents data on vaccine prophylaxis in Russia. A sophisticated analysis of the data available in the literature on approaches to vaccination against tuberculosis in different countries of the world is provided. The results of the studies made by Russian investigators to develop different regimes of BCG re-administrations an their frequencies are given. The fact that it is necessary to change a tuberculosis prophylaxis calendar under the present conditions, by keeping in mind the age of a child and the epidemic situation in the country's region, has been established. A particular section is dedicated to the problem associated with the occurrence of complications in response to tuberculosis vaccine. Based on the Federal Center data on complications due to BCG/ BCG-M, the authors provide information on the incidence and pattern of complications occurring in Russia. As compared with 1995, the incidence of postvaccination complications slightly changed (21.1 in 100,000 in 1995 versus 20.3 in 2002-2003). In the children inoculated at a maternity hospital, postvaccination lymphadenitis was observed 2 times more frequently than in those vaccinated at a polyclini (77.1 and 37% of cases, respectively) and cold abscesses were 3.3 times less frequently than those inoculated at the polyclinic (19.1 and 63% of cases, respectively). The study has ascertained main reasons for the higher incidence of severe complications as BCG ostitis.

The paper gives data on the prevalence of nonspecific lung disease in patients with pulmonary tuberculosis, the specific features of diagnosis and treatment of their concomitance in 3453 patients with pulmonary tuberculosis. It shows the low detection rate of nonspecific lung diseases in patients with pulmonary diseases. The high error rate has been established in the diagnosis of pulmonary tuberculosis at health care facilities. There is evidence that the use of current therapy for bronchial obstructive syndrome with inhaled cholinolytics and beta2-agonists in patients with pulmonary tuberculosis causes a reduction in the intensity of respiratory symptoms and an increase in forced expiratory volume in one second.

The paper presents the results of a population-based, geneticoepidemiological, and immunological study conducted in two regions of Tatarstan. The population-based risks for tuberculosis were established for males and females. Based on the population and family data, the authors calculated the genetic liability to tuberculosis, namely hereditability that is in the range of 0.8 to 1.0 and includes the contribution of nongenetic and environmental factors. Analysis of the results of immunogenetic studies of the northwestern region of Tatarstan has ascertained that patients have an association with the HLA antigen B22, in the Kama Region there is an association with other HLA antigens: B12 and B16. The higher frequency of the HLA antigens B28 and CW1 in healthy individuals as compared with that in patients with pulmonary tuberculosis (PT) suggests the resistance of PT carriers of these antigens for the disease. A study of the distribution of HLA genes by polymerase chain reaction has established the association of the disease with the DR-B1-15 genes in the Kama Region.

Special geoinformation technologies (GIS), a new method for the pictorial data presentation as space-time ratios, have emerged in the past decade. The paper considers the theory of geoinformation analysis and the possibilities of applying GIS for tuberculosis monitoring. GIS may be effectively used in phthisiology only provided that the routine procedures for tuberculosis detection are practiced widely. GIS analysis may assist in detecting tuberculosis when contacts cannot be monitored in the usual fashion. Its results may be used to correct tuberculosis-controlling measures towards their point application. Extended studies can answer to what extent, the efficiency of tuberculosis-controlling measure will increase when they are used in the most possible tuberculosis transmission areas determined by the GIS techniques.

The paper shows the research directions of the staff of the laboratory of pathomorphology and electron microscopy, which cover the period from 1924 to the present time, which can be conventionally divided into 4 stages associated with the leading role of the laboratory's heads: Prof. V.G. Shtefko (1924-1945), Prof. V.I. Puzik (1945-1974), Prof. O.A. Uvarova (1974-1980), and Prof. V.V. Yerokhin (1980 up to the present time). The laboratory's researches are the productive path of phthisiomorphology. The tasks of the laboratory have been associated with the problems to be solved by the institute. This applies the morphology, pathogenesis, classification of tuberculosis, and changes in inflammatory reactions in response to the altered Mycobacterium tuberculosis and to specific and pathogenetic actions on tuberculosis. New living conditions give the laboratory's researchers new tasks that require their solution at a new technological level.

Medical and psychological studies have established that the personality of a psychosomatic patient has characteristic specific features that determine his emotional reactions and lead to psychological and physiological destructions. Searching for the specificity of psychogenesis of pulmonary tuberculosis may be guided by the V. N. Myasishchev provisions of psychology of relations and should be aimed at analyzing the patients' significant experiences that cause their prolonged affective tension. This paper defines the tasks of studying the psychological and neuropsychological features of patients with pulmonary tuberculosis and specifies an adequate set of psychodiagnostic procedures to solve the put problems. The findings may provide insight into the specific character of psychogenesis of pulmonary tuberculosis and into a relationship of the psychological traits of patients with this nosological entity to the physiological processes at the somatic and cerebral level.

The paper describes the follow-up and treatment of patients with tuberculosis concurrent with HIV infection in Moscow in 2004-2005. Major epidemiological parameters, such as morbidity, mortality, and prevalence of this comorbidity, are given. Analysis of these indices suggests that the epidemic situation associated with tuberculosis concurrent with HIV infection became worse in the past 2 years. As compared with 2004, in 2005 the number of such patients increased from 294 to 445, including that of first detected patients rose from 123 to 174. In this group of patients, there was a preponderance of young males aged 29 to 39 years. Most patients with this pathology suffered from drug addiction and alcoholism and other concomitant diseases. The bulk of them were unemployed and disabled. In the HIV-infected, the clinical forms of tuberculosis were severe with a predominance of acute and disseminated processes; the rate of drug resistance, including multidrug resistance, was high, which made treatment difficult and resulted in high mortality.

The paper provides the data of analysis of antituberculous care to teenagers in Moscow and characterizes its problems. Emphasis is placed on the tense and unstable situation associated with the detection of the disease in this age group. In the bulk of adolescents, the disease is identifies when they come to see a doctor, including at somatic hospitals. Active tuberculosis detection techniques (tuberculin diagnosis and fluorography) fail to produce adequate effect mainly due to organizational problems (the bulk of teenagers are outside the organized collective bodies or the latter are frequently changed; the detection of tuberculosis in Moscow nonresidents or in whose who enter secondary specialized colleges claims attention). Age-related sociomedical risk factors, such as hormonal rearrangement, comorbidity, a negative attitude towards preventive medical measures, deviant behavior, social family, and dysadaption, are of importance for the development of tuberculosis. A sociomedical portrait of an adolescent with tuberculosis is given. Attention is drawn to the fact that on implementing antituberculous measures, it is a need for an interaction of a tuberculosis-controlling service with general care health network facilities, including those that deal with the problems of social diseases and educational establishments.

A hundred and thirteen case histories of patients with isolated and generalized forms of abdominal tuberculosis were analyzed. The patients' age was 15 to 79 years; there were 86 (76.1%) males and 27 (23.9%) females. The patients were admitted more frequently from other tuberculosis facilities (66.7%) and less frequently from general hospitals (33.3%). In 62 (54.9%) cases, abdominal tuberculosis showed a complicated course. The residents of Moscow and its region, predominantly the unemployed (85.8%), prevailed in the structure of detected patients with abdominal tuberculosis. In the period of 2001 to 2004, there was a rise in the incidence of new-onset abdominal tuberculosis, its rate increased from 4.4 (2001) to 8.3% (2004) of the total number of patients admitted to Moscow clinical hospital No. 7 for extrapulmonary tuberculosis admitted. This gives no way of considering this site of tuberculosis to be rare. In the structure of abdominal tuberculosis, its generalized forms were prevalent (86.7%), which was associated with the late detection of abdominal tuberculosis and the significant increase in the number of HIV-infected patients from 14.3 (2000) to 33.3% (2004). Abdominal organ lesions were more frequently observed in severe generalized pulmonary processes, such as disseminated (45.1%), infiltrative (18.6%) or fibrocavernous (15.9%) tuberculosis. An algorithm of diagnosis of abdominal tuberculosis and the rates of its detection by various studies are presented in the paper. Abdominal tuberculosis was diagnosed in 8.9% of cases by noninvasive comprehensive examination methods, in 18.6% by laparoscopy, and in most cases (57.5%) intraoperatively. In socially dysadapted persons, postmortem abdominal tuberculosis was detected in 15% of cases.

The paper presents data on bed reductions at tuberculosis care facilities in the Sverdlovsk Region. These data are compared with those in the neighboring regions. The main topic of the paper is the advantages of a day hospital over those of a day-and-night one. Indications for admission to a day hospital are presented. The 2004 statistical data on the work of a day hospital are given. The paper shows that hospital-replacing technologies are promising in the treatment and rehabilitation of patients with tuberculosis in the Sverdlovsk Region.

The paper presents the main points of the authors' own concept of the centralization of mycobacteriological service in large towns of the Russian Federation. The main points of step-by-step organizational and methodological measures required to solve this problem are described in detail. Consecutive measures to realize the proposed mycobacteriological service centralization model originated in January 2004 on a model of the Moscow Eastern Administrative District with 1380 thousand inhabitants are described.

The paper describes the most important developmental stages of phthisiomorphology in chronological order, by using as an example the work of the Pathomorphology Laboratory, Central Tuberculosis Research Institute, since its organization. It also shows the stages of phthisiosurgery with the inestimable scientific and practical contribution of the works by L. K. Bogush and his followers from the formation of lung surgery to today's achievements. The authors give examples of the long-term working partnership of surgeons and morphologists in the development of these two disciplines, which was fruitful in deciding many issues of phthisiology.

The paper describes the results of radiometric BACTEC assay of drug susceptibility of Mycobacterium tuberculosis strains, isolated from 81 new cases of tuberculosis, to first- and second-line antituberculosis drugs in four administrative areas of the North-Western Federal District of the Russian Federation. The results of determination of drug susceptibility to the antituberculosis drugs by the absolute concentration method and the BACTEC method are also compared. Primary drug resistance has been revealed in 58.0%; multidrug resistance in 34.6%. Comparison of the results of determination of drug susceptibility by the methods revealed no significant discrepancy between both methods; however, the procedure for drug susceptibility to some drugs requires improvement.

The paper pools the experience gained in the surgical treatment of lung malformations in children and adults, which has been used to develop their current classification. It also presents the outcomes of surgical treatment of acute infectious lung destructions, by taking into account the Marchuk severity index. Modes of surgical treatment of bullous pulmonary emphysema have been provided, which yield minimum postoperative mortality rates (3%). The experience of surgical treatment of 110 patients with cicatrical tracheal stenosis is summarized. The authors also present the results of operations made in 390 patients with Stage III non-small cell carcinoma of the lung, specify indications and procedures for resection of the bifurcation of the trachea when the latter is involved in the tumorous process. They also summarize the experience gained in having performed more than 300 operations in the past 5 years for progressive pulmonary tuberculosis, with 2.7% mortality, and 106 final pneumonectomies for postoperative recurrent pulmonary tuberculosis. The experience with allografting of the trachea (n = 2) and lung (n = 3) is important and little studied in our country.

The paper reviews the development of biochemical studies in phthisiosurgery, by comparing the needs of resuscitation and anesthetic provision of major thoracic operations and the management of the postoperative period. Emphasis is laid on the leading role of biochemical monitoring in the prevention and treatment of postoperative events, such as acute renal failure, metabolic alkalosis, thrombohemorrhagic syndrome, pulmonary thromboembolism, and others. The prospects of further researches dealing with the problems of postoperative pathophysiology are considered in patients with pulmonary tuberculosis.

The paper briefly describes data on the first operations on the lung made in children at the Central Research Institute of Tuberculosis for pulmonary tuberculosis under anesthesia. According to L. K. Bogush's recommendations, the author has first made clinicomorphological and bacteriological comparisons of different pathological tissue from 105 children and adolescents operated on for pulmonary tuberculosis, 81 biopsy specimens being abacillary. Mycobacterium tuberculosis was found in 54.3% of the operative biopsy specimens from the patients long (mean 1.5 to 2 years) treated by antibiotics. L. K. Bogush defined indications for surgical treatment for different clinical forms of pulmonary tuberculosis in children and adolescents. Six hundred and twenty-seven operations were performed in 589 children and adolescents. All types and volumes of lung resections, pneumonectomy, pleuropneumonectomy, pleurectomy, lymphonudulectomy(tomy), and main bronchi occlusion were made. Operations were performed mainly via lateral access, without crossing the ribs.

The paper presents the results of the tuberculosis situation in the penitentiaries of the Republic of Buryatia. It analyzes organizational measures for prevention of tuberculosis and its early detection in the prisoners and reflect the main reasons of the spread of tuberculous infection in the reformatories. The paper also shows the interdepartmental interactions of the medical service of the Ministry of Justice of the Russian Federation in the Republic of Buryatia with the Republican Tuberculosis Dispensary in notifying and controlling the patients who are in the reformatories, as well as the mechanisms of deporting the accused and convicts who suffer from tuberculosis.

The fact that genetic factors largely determine susceptibility to different diseases, including those of infectious nature is beyond question now. Tuberculosis is not an exception in this respect. HLA genes that determine different immunological phenomena make a certain contribution to tuberculosis susceptibility. This paper presents the results of typing using the polymerase chain reaction from the specificities of the HLA gene DRB1 in patients with pulmonary tuberculosis and healthy individuals in different regions of the Republic of Tuva. The studies in these regions of Tuva have revealed a significant positive association of tuberculosis with the specificities of HLA DRb1 13(6) and HLA DRB1 14(6). Analyzing 14 families of patients with tuberculosis has shown that HLA haplotypes from the sick parents who carry the specificities of HLA DRB1 13 and/or DRb1 14 are more frequently transmitted to sick children than to healthy ones. High morbidity in the indigenous dwellers of the Republic of Tuva may be associated with these specificities of the HLA gene DRB1, which is due to the national peculiarities of the native population of this republic.

The paper deals with drug resistance of Mycobacterium tuberculosis in the prisons of the Arkhangelsk Region. The present study was undertaken to examine the spread of multidrug resistance of Mycobacterium tuberculosis and its impact on the outcomes of treatment of new cases of tuberculosis in the penitentiaries of the Arkhangelsk Region.

The paper presents the basic sections of the nonspecific prevention of tuberculosis. The main objective, tasks, and methods for solving the latter are formulated for each section. Emphasis is placed on the social and age groups of the population while doing sanitary and educational work. Attention is given to that it is necessary to evaluate the efficiency of implementation of educational programs, which is important for making amendments when the epidemic situation and the population's sanitary education change.

The paper presents the results of the activities of tuberculosis-controlling facilities and the general medical network rendering an antituberculous care to the population of Russia in 2003. The epidemic situation in Russian remains to be of strain. There is stabilization or an insignificant improvement of some indices of tuberculosis-controlling work.

The paper analyzes the epidemic situation associated with tuberculosis and AIDS in the Republic of Kalmykia and shows the high incidence (21.2%) of tuberculosis in the HIV infected. The authors propose a classification of tuberculosis and AIDS according to the clinical manifestations and outcome of a disease. Tuberculosis associated with HIV infection has been established to run most severely in socially unfavorable groups of patients. The timely and regular preventive treatment of tuberculosis in the development of immunosuppression (CD4, 200 cells or less) makes it possible to postpone and, at times, prevent the development of a tuberculous process in these patients. Combined antiviral therapy permits more effective treatment of tuberculosis.

The activities of two federal and regional tuberculosis sanatoriums for children and adolescents were analyzed. The clinical characteristics and the results of the examination and treatment were studied in 510 patients aged 12-17 years who had various manifestations of tuberculous infection. The beds in the sanatoriums were ascertained to occupy irrationally: the proportion of patients with local forms of tuberculosis there is not more than 30%. Guidelines for selection of children and adolescents with tuberculosis from risk groups and for detection of the disease were developed. A proposal was made to set up consultative and diagnostic centers at the sanatorium basis. The paper shows it possible and expedient to treat children and adolescents with new-onset local, non-destructive forms of tuberculosis under the conditions of a sanatorium.

The paper substantiates and provides evidence for that it is necessary to use summarized estimates to characterize the tuberculosis endemic situation. Some individual epidemiological indices are inadequately estimated to give a correct idea of epidemiological well-being. By using his own method for deriving an integral estimates, the author has analyzed the dynamics of the tuberculosis situation in Russia in 1985 to 2003. Two turning points have been established in the dynamics of the epidemic situation: 1) improvement up to 1991 inclusive and 2) a subsequent deterioration up to 2002, thereafter the epidemic situation had tended to improve. A correlation matrix has been derived, which reflects a correlation of integral estimates with individual epidemiological indices.

The paper presents the results of the assessment of the quality of cultural detection and determination of Mycobacterium tuberculosis (MBT) sensitivity at Russia's public health laboratories, which has been made by the Federal System for External Assessment of the Quality of Clinical Laboratory Studies in 2002-2003. The "Bacteriological Detection" Section involved 102 laboratories, of them 57 laboratories also participated in the section "Detection of Drug Resistance". Sixty-three laboratories operated as part of specialized tuberculosis-controlling service facilities and 39 laboratories worked as part of general medical care therapeutic-and-prophylactic institutions. A set of 5 lyophilized samples containing 2.5 x 10(6) M. tuberculosis H37Rv (n = 1); 2.5 x 10(4) M. tuberculosis H37Rv (n = 2); M. fortuitum (n = 1); E. coli in the mixture with autoclaving-killed M. tuberculosis H37Rv (n = 1). 77% of the laboratories could detect in the cultural sample with a high content of M. tuberculosis, by obtaining a correct result; 85% revealed MBT if only in every three MBT-containing samples; 15% of the laboratories could not find MBT in none of the three positive samples. 12% of the laboratories took the growth of microorganisms in the M. fortuitum-containing sample for that of M. tuberculosis. 58% of the laboratories obtained correct results if only in one sample containing M. tuberculosis H37Rv; 42% reported the detection of resistance to one or several antituberculous drugs in the samples containing the drug-sensitive strain H37Rv (a false drug resistance). All the results of determination of drug resistance (DR) in the M. fortium-containing sample were correct. The findings suggest that it is necessary to increase the professional competence of laboratory personnel to the level that ensures the adequate of fulfillment of the standard protocols for detecting MTB and determining DR, which have been introduced by the Ministry of Health of the Russian Federation through its order No. 109 on March 21, 2003.

According to the data of the WHO European Regional Office, Russia is now among the countries of Europe, in which tuberculosis and HIV infection are a most pressing problem. In this connection, it has been necessary to promptly determine measures to improve the epidemiological situation. For their elaboration within the high-leveled working tuberculosis group, the ad hoc group "Tuberculosis in patients with HIV infection" working jointly with WHO specialists has been set up in Russia. This paper gives the basic activity lines required for organizing the systems of prevention, epidemiological surveillance, detection of tuberculosis, medical and diagnostic antituberculous aid to patients with HIV infection in Russia.

The paper presents the organizational aspects of antituberculous care delivered at penitentiary institutions of the Russian Federation. The priorities of development, including the interaction with civil public health care of Russia and the continuation of tuberculosis-controlling activities jointly with international organizations, are identified.

The paper presents the results of sociohygienic and epidemiological monitoring of 133 children and adolescents from familial tuberculous foci. Primary infection with Mycobacterium tuberculosis (MBT) was detected in 26 (19.5 +/- 3.4) patients and its carriage was found in 60 (45.1 +/- 4.3 per 100 contact children and adolescents). The rate of primary MBT infection and carriage is largely determined by the social personality of a bacterial isolating personality, by the level of his/her sanitary culture, by his/her adequate attitude towards treatment, by the duration and nature of his/her contacts with those who have had contacts with infected persons, as well as by household and sanitary conditions in the focus. The sources of infection were significantly more frequently fathers, the handicapped or unemployed, chronic alcoholics, prisoners, those who had a low level of sanitary culture, who had an inadequate attitude towards treatment and had a resultant generalized destructive process in the lung and a permanent bacterial carriage.

The paper presents a clinical and social characterization of patients (n = 747) who died from tuberculosis in Volgograd during 2000-2002 on the basis of an analysis of all fatal cases. The sociomedical factors influencing the mortality of patients with tuberculosis have been determined and the sociomedical portrait of a patient with tuberculosis has been created.

The paper describes the molecular genetic characteristics of M. tuberculosis (MT) strains isolated from 114 patients with pulmonary tuberculosis in the penitentiary system of the Arkhangelsk Region. The sensibility to the first-line antituberculous drugs was determined by the radiometric technique BACTEC; rpoB gene mutations were identified by Inno-Lipa, genotyping was made by the RFLPA assay and spoligotyping. The spread of MT of the genotype Beijing in the penitentiary system was found to be 76.3%. The high rate (79.8%) of the clustering pattern is indicative of active transmission of tuberculosis. The transmission of the Beijing genotype MBT strains was higher (96.6%) than that of other genetypes (25.9%). A multifactorial analysis has shown that streptomycin resistance is independently associated with the infection with the strain of MBT of the genotype Beijing (p = 0.02); the circulation and active transmission of Beijing among the population present a human health threat and an endemic risk from the spread of drug-resistant pulmonary tuberculosis.

The paper analyzes the incidence of tuberculous exudative pleurisy (TEP) in children and adolescents in 30 administrative subjects of 7 Russian Federal Okrugs in 1992-2000. TEP was detected in 957 individuals, including 451 (5.3%) children and 506 (11.8%) adolescents. TEP was detected mainly on referral. Control examinations (tuberculin diagnosis, fluorography, contact examination) identified 163 patients with TEP. Analyzing the sex-age-specific structure in patients with TEP established that the boys (n = 572 (59.8%)) were ill more frequently than the girls (386 (40.2%)). Analyses of age-related changes in TEP revealed a gradual increase in its incidence from to 1 to 17 years of age. The analysis made in 5 Russian Federal Okrugs indicated that in children and adolescents, TEP was not recorded in all cases. In adults, the incidence of TEP corresponded to the total morbidity. The authors have established that this mismatch is due to the misinterpretation of the disease when TEP was not notified as an individual nosological entity, but it was interpreted as a concomitant process in different tuberculous lesions in the lung tissue, intrathoracic lymph nodes, and other organs.

The paper presents the current approaches to organizing and supervising tuberculosis at different levels. The present-day conditions for organizational and methodological measures are analyzed, the concept of supervision is defined and its principles and main elements are described.

The paper presents the results of a study of the distribution of Class I HLA antigens in an ethnic Tatar group (in patients with pulmonary tuberculosis and healthy individuals) in 4 districts of Tatarstan. It has been ascertained that an association with HLA-B22 antigen exists in patients with active pulmonary tuberculosis.

The review paper presents data on the epidemiological features of extrapulmonary tuberculosis in Russia and other countries and on diagnostic problems. It considers the papers of the authors who propose different measures to enhance the efficiency of diagnosis of extrapulmonary tuberculosis.

The paper describes a method for comprehensive analysis of the epidemic situation which is based on the major component technique. The algorithm proposed for comprehensive assessment is highly effective in the retrospective analysis and in the analysis of the current material which includes a great deal of various characteristics that are at first sight occasionally unrelated. The use of the algorithm is shown by the example of analyzing 19 statistical variables that characterize the epidemic situation and different aspects of the work of a tuberculosis-controlling facility in 30 districts of the Novosibirsk Region in a period of 15 years (1985-1999). During processing, the variables fall into two groups: a group of variables that characterize the quality of antituberculosis work and a group of those reflecting the epidemic situation, which were used to divide the districts of the region into several groups.