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Background: The control of tuberculosis (TB) may benefit from a prospective identification of areas where the incidence may increase in addition to the traditionally identified foci of high incidence. We aimed to identify residential areas with growing tuberculosis incidence rates and assess their significance and stability., Methods: We analysed the changes in TB incidence rates using case data georeferenced with spatial granularity to apartment buildings in the territory of Moscow from 2000 to 2019. We identified sparsely distributed areas with significant increases in the incidence rate inside residential areas. We tested the stability of found growth areas to case underreporting via stochastic modelling., Results: For 21 350 cases with smear- or culture-positive pulmonary TB among residents from 2000 to 2019, we identified 52 small-scale clusters of growing incidence rate responsible for 1% of all registered cases. We tested clusters of disease growth for underreporting and found them to be relatively unstable to resampling with case drop-out, but their spatial displacement was small. Territories with a stable increase in TB incidence rate were identified and compared to the rest of the city, which is characterised by a significant decrease in incidence., Conclusions: Identified areas with a tendency for an increase in the TB incidence rate may be important targets for disease control services., Competing Interests: Disclosure of interest: The authors completed the ICMJE Disclosure of Interest Form (available upon request from the corresponding author) and disclose no relevant interests., (Copyright © 2023 by the Journal of Global Health. All rights reserved.)

Ensuring effective epidemiological surveillance of tuberculosis is essential and one of the paramount tasks for any national tuberculosis control program. The article analyzes the organization of the tuberculosis epidemiological monitoring system at the level of the subject, based on the experience of implementing such a system in the city of Moscow in 1996-2020, defines its tasks and principles of its construction. The systems of epidemiological monitoring of tuberculosis, implemented taking into account the developed principles, provide an analysis of the epidemiological situation in the territory, the results of which can be successfully used for making managerial decisions, program-target planning and evaluating the effectiveness of the measures taken.

The present study investigates epidemiological diversity and multidrug resistance spreading among Mycobacterium tuberculosis strains circulating in Moscow, Russian Federation. Among 115 M. tuberculosis strains selected randomly from the sputum of epidemiologically unrelated tuberculosis (TB) patients, multidrug-resistant (MDR) strains predominated. Mutations in the RRDR of the rpoB gene were detected in 64 (83.1%) of 77 rifampicin (RIF)-resistant strains. The Ser531→Leu substitution was prevalent among them (76.5%). Aberrations in the Ser315 codon of katG and/or in the inhA promoter region were found in 79 (84.0%) of 94 isoniazid (INH)-resistant strains. Strains belonging to the Beijing family prevailed. Seventy-one different patterns were identified using the 24-VNTR loci typing scheme. Three main 24-loci VNTR clusters included 34 strains which belonged to the Beijing family. The spoligotyping and 24-loci VNTR typing combination demonstrated maximal discriminatory power. Among the Beijing strains, the MDR phenotype was revealed more frequently than among the others. High genetic heterogeneity of the studied population was shown by the assessment of VNTR loci variability in the analyzed group and in the strains from other parts of Russia. Comparison of the 24-VNTR locus typing and spoligotyping data with revealed resistance-associated mutation allows us to make a suggestion that the active transmission of MDR strains and the independent appearance of drug resistance during chemotherapy occurred in the studied population simultaneously.

Problems in the delivery of antituberculosis care to the pediatric population of Moscow are analyzed. Databases are set up by the statutory forms available in the city's tuberculosis dispensaries and by additional analytical tables from pediatric therapeutic-and-prophylactic institutions, such as children's local polyclinics. In Moscow, there was a reduction in the vaccination coverage of healthy neonatal infants at their discharge from maternity hospitals and departments over a number of years (88.0% in 2008 and 90.3% in 2005). The proportion of non-vaccinated neonates due to their parents' refusal was as high as 3.2% of the annual cohort to be vaccinated at maternal hospital discharge. A more alarming situation is established in children's polyclinics where the share of parents' refusal of tuberculosis vaccination was 60.5% (44.5% in 2005) of all the children who were registered in the children's polyclinics and remained unvaccinated at the end of the year. The low number of contacts per bacteria-excreting person registered in the Moscow dispensaries (2.7% in.2008, 2.5% in 2007, and 2.0% in 2004) suggests that phthisiatricians and epidemiologists did inadequately active work in the foci of tuberculosis infection. Migrants with tuberculosis and socially disadapted persons living in the megapolis are an uncontrolled reservoir of infection. In 2008, there was a surge in the number of tuberculosis children who had been non-vaccinated with BCG vaccine for various reasons--the annual growth rate was +2.96. The possible ways out of the established situation are considered. The authors propose to actively involve not only general practitioners and local pediatricians, but also public organizations into prophylactic work with children. Major attention and resources should be directed to work in the foci of tuberculosis infection; it is necessary to differentiate the use of preventive chemotherapy in children, by taking into account the results of evidence-based medicine to identify the most likely risk factors for the development of the disease.

Because of deterioration of epidemiological situation by tuberculosis, individuals from tuberculous infection foci and social risk group require special care. It is important to integrate efforts of phthisiatric and general therapeutic and prophylactic services in detection of tuberculosis in children and adolescents, to create controlled conditions for conduction of antituberculous measures.

The tuberculosis mortality rate is largely determined by the organization of early identification of patients with this disease in the general population. At present the volume of prophylactic surveys has reduced, but, nevertheless, they are the method of choice in detecting tuberculosis in time. Since the prevalence of tuberculosis greatly differs in different populations, prophylactic examinations must be differential in relation to the risk of disease or epidemiological hazards. Increasing the coverage of prophylactic examinations of risk groups by 10% allows one to increase the identification of patients with tuberculosis by 1.6 times in them, that by 8.0% enhances it by 1.9 times. Since the socioeconomic conditions have changed and the logistics is poor, the most effective existing actions should be taken.

The present-day poor epidemiological conditions are marked by an increase in tuberculosis detection rates (1.43%) with low coverage (28.0%) of the population with preventive fluorographic surveys and a high proportion (39.0%) of young patients (aged 18-39 years) among new cases. The shares of advanced and acute forms of tuberculosis were 7.2 and 11.4%, respectively. A decay phase was detected in 50.6%, 52.6% of patients isolated bacteria. In children, tuberculosis morbidity increased by 28.6% mainly among the unregistered extrafamilial contacts. Most patients (75.8%) detected upon their referral to the polyclinics and general hospitals had a high proportion of extrapulmonary tuberculosis. Thus, the above trends of morbidity show its high potential level.

Tuberculous infection is no longer controllable in Moscow. Tuberculosis ranks first in the structure of morbidity caused by monoinfections. The prevalence of tuberculosis is increasing both among adults and children. Increasing incidence of forms with bacterial release is especially dangerous. Such patients represent the greatest epidemic hazard for the population. In Moscow the situation with tuberculosis is characterized by a notable reservoir of infection among socially maladapted subjects. A special department for this patient population was created in tuberculosis hospital No. 11; besides medical care, the patients are rendered social care there. The situation with tuberculosis in Russia and in Moscow requires urgent measures aimed at stabilization of the epidemiological process.

Homeless patients with tuberculosis form a special group. Being out of therapeutical-and-prophylactic institutions sight and violating elementary sanitary regulations, they are, from an epidemic standpoint, the most dangerous part of a tuberculosis reservoir. Tuberculosis morbidity rates in the homeless are extremely high and tens times as great as those among other populations. The existing system for detecting tuberculosis among the homeless is not very effective. Much better results are achieved by nongovernmental philanthropic institutions where homeless persons apply to for medical and social aids. About half the homeless patients with tuberculosis were referred to Tuberculosis Hospital 11 of the International Organization "Physicians Without Boundaries". The patient's personality is, in general, the most vivid terms, characterized as asthenic; with low intelligence and constitution; asocial, aggressive, and being a carrier of the motive of acquired helplessness. This group of patients needs not only medical efforts, but sociolegal and sociopsychological rehabilitation. The activities of Tuberculosis Hospital 11 wherein a room of social aid and rehabilitation has been functioning since 1995 may be an example of a comprehensive approach to tackling the problem of homeless patients with tuberculosis.

Incidence rate of tuberculosis was ascertained in medical and paramedical staff of antituberculosis institutions (ATI) for adults. For the period 1987-1993 tuberculosis developed in 38 subjects, i.e. 4 times more frequently than in the rest adult population of Russia. The physicians catch the infection 1.2 times less frequently than paramedical personnel. The highest morbidity was observed in the staff of clinical, bacteriological and pathological laboratories. The course of tuberculosis in ATI staff is favourable due to early detection and long-term treatment but is characterized by frequent attendant diseases, resistance and intolerance to antibacterial drugs. Preventive treatment of ATI staff in a special sanatorium enhances their resistance to M. tuberculosis infection and reduces this infection prevalence in tuberculosis contacts.

The problem of pediatric tuberculosis is viewed in terms of its connection with social and medical setting, epidemiological situation in adult tuberculosis. To correct negative trends in tuberculosis prevalence in children efforts should be made to eliminate the infection foci, to promote conditioning of population, to introduce new programs of health care for mothers and children.

The results of study of a tuberculosis infection course in different conditions and its association with BCG revaccination are presented. The Moscow region was tentatively divided into 3 groups of regions. Children of Group 1 were not given revaccination at 7 and 12 years, those of Group 2 at 12 years and those of group 3 received revaccination according to the routine techniques at 7, 12 and 17 years. BCG revaccination withdrawal caused no increase in tuberculosis morbidity and tuberculin sensitivity. Tuberculosis detections were unassociated with the frequency of previous BCG revaccination.

The role of the highest tuberculosis risk groups in the enlargement of dispensary contingents increases under conditions of endemic tuberculosis decline while it is less manifest in the epidemiologically unfavourable regions. Risk contingents of polyclinics should be supplemented by a socially unfavourable group of subjects who together with patients having several risk factors and those with severe diabetes mellitus are the most vulnerable with respect to tuberculosis.

Characteristic features of subjects of the VIA registration group (500 children and adolescents) observed by one of the Moscow children's polyclinic from 1983 to 1987 are given. The rate of primary contamination amounted to an average of 0.75% a year. 92.8% of children and adolescents were infected as a result of an unknown contact, while 7.2% of them had contact with relatives suffering from tuberculosis. In case of conversion of tuberculin reactions, hypersensitivity to tuberculin was seen in 12.2% of the patients and a year later in 4.6% the subjects with persistent hyperergy who were then transferred to the VIB registration group. The following risk factors of contaminating and contacting tuberculosis were found: contact with tuberculosis patients; immunization of poor quality or its absence; hypersensitivity to tuberculin; frequent acute respiratory viral infections and chronic diseases; and unfavourable social and living conditions. The number of these factors should be taken into account since with their growth, the rate of hyperergy and risk of developing the disease are higher. More thorough examination and controlled preventive chemotherapy at a sanatorium are required when 2 or more risk factors are available.