Tuberculosis in Kazakhstan: analysis of risk determinants in national surveillance data

Development of tuberculosis (TB) is determined by various risk factors and the interactions of temporal and spatial distributions. The aim of this study was to identify the most salient risk factors for TB disease as well as multidrug resistant TB (MDR-TB) at the oblast (provincial) level in Kazakhstan

Identifying risk factors associated with smear positivity of pulmonary tuberculosis in Kazakhstan

Background Sputum smear-positive tuberculosis (TB) patients have a high risk of transmission and are of great epidemiological and infection control significance. Little is known about the smearpositive populations in high TB burden regions, such as Kazakhstan. The objective of this study is to characterize the smear-positive population in Kazakhstan and identify associated modifiable risk factors. Methods Data on incident TB cases’ (identified between April 2012 and March 2014) socio-demographic, risk behavior, and comorbidity characteristics were collected in four regions of Kazakhstan through structured survey and medical record review. We used multivariable logistic regression to determine factors associated with smear positivity. Results Of the total sample, 193 (34.3%) of the 562 study participants tested smear-positive. In the final adjusted multivariable logistic regression model, sex (adjusted odds ratio (aOR) = 2.0, 95% CI:1.3–3.1, p < 0.01), incarceration (aOR = 3.6, 95% CI:1.2–11.1, p = 0.03), alcohol dependence (aOR = 2.6, 95% CI:1.2–5.7, p = 0.02), diabetes (aOR = 5.0, 95% CI:2.4–10.7, p < 0.01), and physician access (aOR = 2.7, 95% CI:1.3–5.5p < 0.01) were associated with smear-positivity. Conclusions Incarceration, alcohol dependence, diabetes, and physician access are associated with smear positivity among incident TB cases in Kazakhstan. To stem the TB epidemic, screening, treatment and prevention policies should address these factors

Tuberculosis in Kazakhstan: analysis of risk determinants in national surveillance data

Background: Development of tuberculosis (TB) is determined by various risk factors and the interactions of temporal and spatial distributions. The aim of this study was to identify the most salient risk factors for TB disease as well as multidrug resistant TB (MDR-TB) at the oblast (provincial) level in Kazakhstan. Methods: Correlational and descriptive analyses were conducted at the oblast and national level using data provided by the country’s National Institute of Geography (NIG) and the National Tuberculosis Program (NTP). Reported incident case notification rates (CNRs) and prevalence vary by oblast, thus the study investigated which determinants contributed to this regional variation and compared burdens among oblasts. Results: The results showed that while tuberculosis CNRs decreased over the study period, MDR-TB conversely increased. Two oblasts -Atyrauskaya and Mangystauskaya - presented especially significant anomalies with large decreases in TB incident CNRs coupled with comparatively large increases in MDR-TB incident CNRs. Conclusion: Understanding the distribution of TB and MDR-TB cases and associated risk factors, especially the “unknown risk factor” categorization points to the need for future research

Molecular and Genetic Research in Tuberculosis Clinical Practice and Epidemiology

Introduction. Tuberculosis (TB) remains a global public health problem. In order for multi-drug resistant tuberculosis (MDR-TB) to be more effectively managed, there is a need for better tools for diagnosis, treatment, and prevention. The decline of TB incidence and mortality in Kazakhstan during last decade was accompanied with consistent growth of MDR-TB. This study aimed to investigate genotype characteristics of Mycobacterium tuberculosis (MT) isolated from TB patients from different regions of the country and its clinical and epidemiological significance. Methods. Over 500 clinical MT isolates from pulmonary TB patients between 2003-2008 were genotyped using spoligotyping, MIRU-VNTR, IS6110 RFLP, and hybridization on an oligonucleotide biochip “TB–biochip.” Results. Out of  250 isolates with interpretable results, 31 different spoligopatterns were detected. The Beijing genotype was the most predominant lineage detected (71.6%), characterized by heterogenicity on ETR A, B, C, D, and E markers, and 56.6% of them had an allelic profile 42435. The Beijing genotype and dominating variant strains have a high transmission rate, a high rate of primary MDR (associated with infiltrating lung TB and complications), and a high level resistance to rifampicin and izoniazid due to mutation of rpoB531TTG and katG315ACC. MIRU-VNTR–typing by 15 loci of 33 isolates from 13 family TB foci revealed that strains from supposed sources and contact persons completely coincide in only 5 foci in the genomic structure. Conclusion. There is a heterogeneous pool of genotypes that circulate in Kazakhstan, with the Beijing lineage being the most predominant. It appears that at the present stage of circulation , MT Beijing genotype has an endemic character. However, clonal spreading of epidemiologically and clinically significant MDR strains of this genotype is also a serious threat to the population. To increase TB control efficiency and prevent further transmission, it is necessary to compile a modern countrywide system of microbiological monitoring for the agent by use of a computer bank of spoligotyping and MIRU-VNTR-typing profiles of circulating strains

Tuberculosis in Kazakhstan: analysis of risk determinants in national surveillance data

Abstract Background Development of tuberculosis (TB) is determined by various risk factors and the interactions of temporal and spatial distributions. The aim of this study was to identify the most salient risk factors for TB disease as well as multidrug resistant TB (MDR-TB) at the oblast (provincial) level in Kazakhstan. Methods Correlational and descriptive analyses were conducted at the oblast and national level using data provided by the country’s National Institute of Geography (NIG) and the National Tuberculosis Program (NTP). Reported incident case notification rates (CNRs) and prevalence vary by oblast, thus the study investigated which determinants contributed to this regional variation and compared burdens among oblasts. Results The results showed that while tuberculosis CNRs decreased over the study period, MDR-TB conversely increased. Two oblasts -Atyrauskaya and Mangystauskaya - presented especially significant anomalies with large decreases in TB incident CNRs coupled with comparatively large increases in MDR-TB incident CNRs. Conclusion Understanding the distribution of TB and MDR-TB cases and associated risk factors, especially the “unknown risk factor” categorization points to the need for future research.</p

Study population characteristics among 562 total and smear-positive participants, Kazakhstan, 2012–2014.

<p>Study population characteristics among 562 total and smear-positive participants, Kazakhstan, 2012–2014.</p

Crude and Adjusted Associations with Smear-positive Among 480 Pulmonary Tuberculosis Cases, Kazakhstan, 2012–2014.

<p>Crude and Adjusted Associations with Smear-positive Among 480 Pulmonary Tuberculosis Cases, Kazakhstan, 2012–2014.</p