Understanding Of Tuberculosis Transmission Research Articles

Determinants of correct knowledge on tuberculosis transmission and self-reported tuberculosis prevalence among general population aged 15-49 years in Myanmar.

Myanmar has been identified as one of the tuberculosis (TB) high-burden countries and having an understanding of TB transmission is vital for personal infection prevention as well as preventing transmission to others. This study aimed to identify the determinants of correct knowledge on TB transmission and self-reported TB prevalence among general population in Myanmar. This is a cross-sectional study using secondary data from Myanmar demographic and health survey 2015-16. The determinants of correct knowledge on TB transmission mode and self-reported prevalence of TB were assessed using multivariable logistic regression models. Weighted estimates were provided in all analyses to account for the multistage sampling design used in the survey. Among the respondents, less than half (44.6%, 95% CI: 43.9, 45.4) had the overall correct knowledge about TB transmission and misconceptions. Older age group, female gender, those with higher education and higher socioeconomic status, and exposed to mass media at least once a week, residents from the delta and lowland region or plain areas were more likely to have correct knowledge about TB transmission. The overall prevalence rate of self-reported TB was 2.6% (95%CI: 2.4, 2.9) and the prevalence was higher among older age group and males. Our study highlights the need for targeted efforts to improve awareness and understanding of TB transmission among general population in Myanmar. The study suggests the implementation of appropriate, innovative, and comprehensive targeted TB education and communication strategies.

Interpreting whole genome sequencing for investigating tuberculosis transmission: a systematic review.

BackgroundWhole genome sequencing (WGS) is becoming an important part of epidemiological investigations of infectious diseases due to greater resolution and cost reductions compared to traditional typing approaches. Many public health and clinical teams will increasingly use WGS to investigate clusters of potential pathogen transmission, making it crucial to understand the benefits and assumptions of the analytical methods for investigating the data. We aimed to understand how different approaches affect inferences of transmission dynamics and outline limitations of the methods.MethodsWe comprehensively searched electronic databases for studies that presented methods used to interpret WGS data for investigating tuberculosis (TB) transmission. Two authors independently selected studies for inclusion and extracted data. Due to considerable methodological heterogeneity between studies, we present summary data with accompanying narrative synthesis rather than pooled analyses.ResultsTwenty-five studies met our inclusion criteria. Despite the range of interpretation tools, the usefulness of WGS data in understanding TB transmission often depends on the amount of genetic diversity in the setting. Where diversity is small, distinguishing re-infections from relapses may be impossible; interpretation may be aided by the use of epidemiological data, examining minor variants and deep sequencing. Conversely, when within-host diversity is large, due to genetic hitchhiking or co-infection of two dissimilar strains, it is critical to understand how it arose. Greater understanding of microevolution and mixed infection will enhance interpretation of WGS data.ConclusionsAs sequencing studies have sampled more intensely and integrated multiple sources of information, the understanding of TB transmission and diversity has grown, but there is still much to be learnt about the origins of diversity that will affect inferences from these data. Public health teams and researchers should combine epidemiological, clinical and WGS data to strengthen investigations of transmission.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-016-0566-x) contains supplementary material, which is available to authorized users.

Six Degrees of Separation: Use of Social Network Analysis to Better Understand Outbreaks of Nosocomial Transmission of Extensively Drug-Resistant Tuberculosis

Six Degrees of Separation: Use of Social Network Analysis to Better Understand Outbreaks of Nosocomial Transmission of Extensively Drug-Resistant Tuberculosis

The Ontario Universal Typing of Tuberculosis (OUT-TB) Surveillance Program – What It Means to You

Tuberculosis (TB) is a serious disease that is transmitted primarily by the airborne route. Effective disease control and outbreak management requires the timely diagnosis, isolation and treatment of infected individuals with active disease; contact tracing to identify secondary cases likely to benefit from treatment of latent infection; and laboratory identification or confirmation of epidemiologically linked cases. TB genotyping enables the comparison of Mycobacterium tuberculosis complex (MTBC) strains and the identification of cases that may or may not be linked. The increased availability of molecular methods for genotyping has allowed for greater discrimination of MTBC strains and greatly enhanced understanding of TB transmission patterns. To improve TB surveillance and control in Ontario, the Public Health Laboratories of the Ontario Agency for Health Protection and Promotion has introduced the Ontario Universal Typing of Tuberculosis (OUT-TB) Surveillance Program. The first isolate from every new TB case will be genotyped with two rapid molecular methods: spoligotyping and mycobacterial interspersed repetitive unit-variable-number tandem repeat typing. MTBC isolates with nonunique genotypes and, thus, potentially linked to other TB cases, will also be genotyped by IS6110 restriction fragment length polymorphism analysis. By providing TB control programs using these new genotyping tools, and using traditional and new case investigation methods (eg, social network analysis), this new program will provide a clearer picture of TB in Ontario, and permit more effective use of public health resources and improve disease control.

Mycobacterium tuberculosis: spoligotypes in the Carabobo state, Venezuela

In order to study the genetic variability of Mycobacterium tuberculosis circulating in the Carabobo State at Venezuela, 317 strains of M. tuberculosis isolated from patients living in different health districts whose acid fast smears were positive, were included. Each strain was characterized by spoligotyping and the pattern compared with the national and worldwide SpolDB4.0 databases; 220 isolates (69.4%) were grouped in 24 clusters, being LAM the most common family (34%). In contrast to other Venezuelan regions, the most common Carabobo spoligotype was number 605, with 46 isolates (14.5%). In addition, there were 97 (30.6%) orphan spoligotypes, 19 of which are found in SpolDB4.0, and 78 non described. Co-infection with human immunodeficiency virus was detected in 11 patients (3.5%). These results show high genotypic variability of M. tuberculosis in the region, contributing with new information for a better understanding of tuberculosis transmission in Venezuela.

Mycobacterium tuberculosis: Espoligotipos en el Estado Carabobo, Venezuela

In order to study the genetic variability of Mycobacterium tuberculosis circulating in the Carabobo State at Venezuela, 317 strains of M. tuberculosis isolated from patients living in different health districts whose acid fast smears were positive, were included. Each strain was characterized by spoligotyping and the pattern compared with the national and worldwide SpolDB4.0 databases; 220 isolates (69.4%) were grouped in 24 clusters, being LAM the most common family (34%). In contrast to other Venezuelan regions, the most common Carabobo spoligotype was number 605, with 46 isolates (14.5%). In addition, there were 97 (30.6%) orphan spoligotypes, 19 of which are found in SpolDB4.0, and 78 non described. Co-infection with human immunodeficiency virus was detected in 11 patients (3.5%). These results show high genotypic variability of M. tuberculosis in the region, contributing with new information for a better understanding of tuberculosis transmission in Venezuela.

Tuberculosis Transmission Based on Molecular Epidemiologic Research

Molecular genotyping techniques developed during the past decade and conventional epidemiological methods have been used synergistically in studies of the transmission and pathogenesis of Mycobacterium tuberculosis. Research studies assessing contacts and outbreaks, risk factors for ongoing transmission, and exogenous reinfection with M. tuberculosis have advanced with applied molecular epidemiologic techniques. In addition, molecular epidemiologic approaches have enabled scientists to assess the impact of drug resistance on the transmission and pathogenesis of M. tuberculosis and to identify strains with broad temporal and spatial distributions. In the near future, the intersection of molecular epidemiology, bacterial population genetics, comparative genomics, immunology, and other disciplines will further our understanding of tuberculosis transmission and pathogenesis, contributing to the development of effective drugs and a vaccine against this important human pathogen.