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Zoonoses and Public Health Nov 2021Tuberculosis (TB) is a chronic communicable bacterial disease caused by Mycobacterium tuberculosis complex (MTBC) species. M. tuberculosis is the main causative agent... (Meta-Analysis)
Meta-Analysis Review
Tuberculosis (TB) is a chronic communicable bacterial disease caused by Mycobacterium tuberculosis complex (MTBC) species. M. tuberculosis is the main causative agent of human TB, and cattle are the primary host of Mycobacterium bovis; due to close interaction between cattle and humans, M. bovis poses a zoonotic risk. This review summarizes and estimates the prevalence of M. bovis infection among human cases. Studies reporting TB prevalence data that were published in English during 10 years from 20 April 2009 to 17 April 2019 were identified through search of PubMed and other sources. Quality of studies and risk of bias were assessed using standard tools for prevalence study reports. Characteristics of included studies and their main findings were summarized in tables and discussed with narrative syntheses. Meta-analysis was performed on 19 included studies, with a total of 7,185 MTBC isolates identified; 702 (9.7%) of them were characterized as of subspecies M. bovis, but there was a large prevalence difference between the studies, ranging from 0.4% to 76.7%. The genotyping-based studies reported significantly lower prevalence of zoonotic TB than did the studies based on older techniques. The overall pooled prevalence of M. bovis aggregated from all included studies was 12.1% of the total MTBC isolates, while the corresponding pooled figure from the 14 genotyping-based studies was only 1.4%. Generally, human M. bovis cases reported from different countries of the world suggest that the impact of zoonotic TB is still important in all regions. However, it was difficult to understand the true picture of the disease prevalence because of methodological differences. Future investigations on zoonotic TB should carefully consider these differences when evaluating prevalence results.
Topics: Animals; Cattle; Cattle Diseases; Humans; Mycobacterium bovis; Mycobacterium tuberculosis; Prevalence; Tuberculosis
PubMed: 34169644
DOI: 10.1111/zph.12868 -
The Lancet. Infectious Diseases Jan 2017Mycobacterium tuberculosis is recognised as the primary cause of human tuberculosis worldwide. However, substantial evidence suggests that the burden of Mycobacterium... (Review)
Review
Mycobacterium tuberculosis is recognised as the primary cause of human tuberculosis worldwide. However, substantial evidence suggests that the burden of Mycobacterium bovis, the cause of bovine tuberculosis, might be underestimated in human beings as the cause of zoonotic tuberculosis. In 2013, results from a systematic review and meta-analysis of global zoonotic tuberculosis showed that the same challenges and concerns expressed 15 years ago remain valid. These challenges faced by people with zoonotic tuberculosis might not be proportional to the scientific attention and resources allocated in recent years to other diseases. The burden of zoonotic tuberculosis in people needs important reassessment, especially in areas where bovine tuberculosis is endemic and where people live in conditions that favour direct contact with infected animals or animal products. As countries move towards detecting the 3 million tuberculosis cases estimated to be missed annually, and in view of WHO's end TB strategy endorsed by the health authorities of WHO Member States in 2014 to achieve a world free of tuberculosis by 2035, we call on all tuberculosis stakeholders to act to accurately diagnose and treat tuberculosis caused by M bovis in human beings.
Topics: Animals; Cattle; Humans; Mycobacterium bovis; Mycobacterium tuberculosis; Tuberculosis; Tuberculosis, Bovine; Zoonoses
PubMed: 27697390
DOI: 10.1016/S1473-3099(16)30139-6 -
Diabetes mellitus and latent tuberculosis infection: an updated meta-analysis and systematic review.BMC Infectious Diseases Nov 2023Previous studies have demonstrated an association between diabetes mellitus (DM) and latent tuberculosis infection (LTBI). This study was conducted to update the current... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Previous studies have demonstrated an association between diabetes mellitus (DM) and latent tuberculosis infection (LTBI). This study was conducted to update the current understanding of the association between DM and LTBI. By conducting a systematic review and meta-analysis using adjusted odds ratios (aOR) or risk ratios (aRR), we aimed to further explore the association between DM and LTBI and provide essential reference for future research.
METHODS
We conducted comprehensive searches in Embase, Cochrane Library, and PubMed without imposing any start date or language restrictions, up to July 19, 2022. Our study selection encompassed observational research that compared from LTBI positive rates in both DM and non-DM groups and reported aRR or aOR results. The quality of the included studies was assessed utilizing the Newcastle-Ottawa Scale. Pooled effect estimates were calculated using random-effects models, along with their associated 95% confidence intervals (CI).
RESULTS
We included 22 studies involving 68,256 subjects. Three cohort studies were eligible, with a pooled aRR of 1.26 (95% CI: 0.71-2.23). Nineteen cross-sectional studies were eligible, with a pooled aOR of 1.21 (95% CI: 1.14-1.29). The crude RR (cRR) pooled estimate for three cohort studies was 1.62 (95% CI: 1.03-2.57). Among the cross-sectional studies we included, sixteen studies provided crude ORs, and the crude OR (cOR) pooled estimate was 1.64 (95% CI: 1.36-1.97). In the diagnosis of diabetes, the pooled aOR of the HbA1c group was higher than that of self-reported group (pooled aOR: 1.56, 95% CI: 1.24-1.96 vs. 1.17, 95% CI: 1.06-1.28).
CONCLUSION
Our systematic review and meta-analysis suggest a positive association between DM and LTBI. Individuals with DM may have a higher risk of LTBI compared to those without DM. These findings provide important insights for future research and public health interventions in managing LTBI in diabetic populations.
Topics: Humans; Latent Tuberculosis; Cross-Sectional Studies; Diabetes Mellitus; Tuberculin Test; Cohort Studies; Risk Factors; Observational Studies as Topic
PubMed: 37940866
DOI: 10.1186/s12879-023-08775-y -
The Journal of Infection Dec 2018Since the risk of multidrug-resistant tuberculosis (MDR-TB) may depend on the setting, we aimed to determine the associations of risk factors of MDR-TB across different... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
Since the risk of multidrug-resistant tuberculosis (MDR-TB) may depend on the setting, we aimed to determine the associations of risk factors of MDR-TB across different regions.
METHODS
A systematic review and meta-analysis was performed with Pubmed and Embase databases. Information was retrieved on 37 pre-defined risk factors of MDR-TB. We estimated overall Mantel-Haenszel odds ratio as a measure of the association.
RESULTS
Factors of previous TB disease and treatment are the most important risk factors associated with MDR-TB. There was also a trend towards increased risk of MDR-TB for patients 40 years and older, unemployed, lacking health insurance, smear positive, with non-completion and failure of TB treatment, showing adverse drug reaction, non-adherent, HIV positive, with COPD and with M. Tuberculosis Beijing infection. Effect modification by geographical area was identified for several risk factors such as male gender, married patients, urban domicile, homelessness and history of imprisonment.
CONCLUSIONS
Assessment of risk factors of MDR-TB should be conducted regionally to develop the most effective strategy for MDR-TB control. Across all regions, factors associated with previous TB disease and treatment are essential risk factors, indicating the appropriateness of diagnosis, treatment and monitoring are an important requirements.
Topics: Antitubercular Agents; Global Health; Host Microbial Interactions; Humans; Latent Tuberculosis; Mycobacterium tuberculosis; Odds Ratio; Risk Assessment; Risk Factors; Tuberculosis, Multidrug-Resistant
PubMed: 30339803
DOI: 10.1016/j.jinf.2018.10.004 -
Journal of Infection in Developing... Nov 2021Leprosy and tuberculosis are endemic in several countries. The aim of this study was to describe factors associated with co-infection among both diseases. A systematic...
Leprosy and tuberculosis are endemic in several countries. The aim of this study was to describe factors associated with co-infection among both diseases. A systematic review was carried out, following the Quality of Reporting of Meta-analyses, with the PubMed and Biblioteca Virtual em Saúde (BVS) portals as sources, under eligibility criteria: cross-sectional, cohort, case-control studies or case reports, published in Portuguese, English, French and Spanish, from 2015 to 2020. Studies that dealt with leprosy and tuberculosis not in the context of co-infection were excluded. The initial phase resulted in 1079 articles; 13 went on to a final stage. All were case reports. Thirteen (72.2%) participants were male, aged between 17 and 72 years. Life habits were found in 8 (44.4%) of the articles: 1 (12.5%) reported chronic alcoholism, 1 (12.5%) reported chronic smoking and alcoholism and 1(12.5%) reported chronic smoking, alcoholism and use of illicit drugs. Pathological history was mentioned by 14 (77.8%) patients; 1 (7.1%) reported HIV/AIDS. Three patients (16.6%) described previous history of tuberculosis and/or leprosy. Seven (38.9%) participants reported vaccination with Bacillus Calmette-Guérin. The pulmonary form of tuberculosis predominated and one third of the patients presented resistance to, at least, one tuberculostatic. All cases had multibacillary leprosy. The study did not highlight any comorbidity, and there was no change in the course of the conditions owing to co-infection.
Topics: Adolescent; Adult; Aged; Coinfection; Female; Humans; Leprosy; Male; Middle Aged; Tuberculosis, Pulmonary; Young Adult
PubMed: 34898480
DOI: 10.3855/jidc.14308 -
JAMA May 2023In the US, tuberculosis remains an important preventable disease, including active tuberculosis, which may be infectious, and latent tuberculosis infection (LTBI), which...
IMPORTANCE
In the US, tuberculosis remains an important preventable disease, including active tuberculosis, which may be infectious, and latent tuberculosis infection (LTBI), which is asymptomatic and not infectious but can later progress to active disease. The precise prevalence rate of LTBI in the US is difficult to determine; however, estimated prevalence is about 5.0%, or up to 13 million persons. Incidence of tuberculosis varies by geography and living accommodations, suggesting an association with social determinants of health.
OBJECTIVE
To update its 2016 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on LTBI screening and treatment in asymptomatic adults seen in primary care, as well as the accuracy of LTBI screening tests.
POPULATION
Asymptomatic adults 18 years or older at increased risk for tuberculosis.
EVIDENCE ASSESSMENT
The USPSTF concludes with moderate certainty that there is a moderate net benefit in preventing active tuberculosis disease by screening for LTBI in persons at increased risk for tuberculosis infection.
RECOMMENDATION
The USPSTF recommends screening for LTBI in populations at increased risk. (B recommendation).
Topics: Adult; Humans; Latent Tuberculosis; Mass Screening; Risk Assessment; Tuberculosis; United States; Social Determinants of Health
PubMed: 37129649
DOI: 10.1001/jama.2023.4899 -
The Lancet. Global Health Sep 2022BCG vaccines are given to more than 100 million children every year, but there is considerable debate regarding the effectiveness of BCG vaccination in preventing... (Meta-Analysis)
Meta-Analysis
Infant BCG vaccination and risk of pulmonary and extrapulmonary tuberculosis throughout the life course: a systematic review and individual participant data meta-analysis.
BACKGROUND
BCG vaccines are given to more than 100 million children every year, but there is considerable debate regarding the effectiveness of BCG vaccination in preventing tuberculosis and death, particularly among older children and adults. We therefore aimed to investigate the age-specific impact of infant BCG vaccination on tuberculosis (pulmonary and extrapulmonary) development and mortality.
METHODS
In this systematic review and individual participant data meta-analysis, we searched MEDLINE, Web of Science, BIOSIS, and Embase without language restrictions for case-contact cohort studies of tuberculosis contacts published between Jan 1, 1998, and April 7, 2018. Search terms included "mycobacterium tuberculosis", "TB", "tuberculosis", and "contact". We excluded cohort studies that did not provide information on BCG vaccination or were done in countries that did not recommend BCG vaccination at birth. Individual-level participant data for a prespecified list of variables, including the characteristics of the exposed participant (contact), the index case, and the environment, were requested from authors of all eligible studies. Our primary outcome was a composite of prevalent (diagnosed at or within 90 days of baseline) and incident (diagnosed more than 90 days after baseline) tuberculosis in contacts exposed to tuberculosis. Secondary outcomes were pulmonary tuberculosis, extrapulmonary tuberculosis, and mortality. We derived adjusted odds ratios (aORs) using mixed-effects, binary, multivariable logistic regression analyses with study-level random effects, adjusting for the variable of interest, baseline age, sex, previous tuberculosis, and whether data were collected prospectively or retrospectively. We stratified our results by contact age and Mycobacterium tuberculosis infection status. This study is registered with PROSPERO, CRD42020180512.
FINDINGS
We identified 14 927 original records from our database searches. We included participant-level data from 26 cohort studies done in 17 countries in our meta-analysis. Among 68 552 participants, 1782 (2·6%) developed tuberculosis (1309 [2·6%] of 49 686 BCG-vaccinated participants vs 473 [2·5%] of 18 866 unvaccinated participants). The overall effectiveness of BCG vaccination against all tuberculosis was 18% (aOR 0·82, 95% CI 0·74-0·91). When stratified by age, BCG vaccination only significantly protected against all tuberculosis in children younger than 5 years (aOR 0·63, 95% CI 0·49-0·81). Among contacts with a positive tuberculin skin test or IFNγ release assay, BCG vaccination significantly protected against tuberculosis among all participants (aOR 0·81, 95% CI 0·69-0·96), participants younger than 5 years (0·68, 0·47-0·97), and participants aged 5-9 years (0·62, 0·38-0·99). There was no protective effect among those with negative tests, unless they were younger than 5 years (0·54, 0·32-0·90). 14 cohorts reported on whether tuberculosis was pulmonary or extrapulmonary (n=57 421). BCG vaccination significantly protected against pulmonary tuberculosis among all participants (916 [2·2%] in 41 119 vaccinated participants vs 334 [2·1%] in 16 161 unvaccinated participants; aOR 0·81, 0·70-0·94) but not against extrapulmonary tuberculosis (106 [0·3%] in 40 318 vaccinated participants vs 38 [0·2%] in 15 865 unvaccinated participants; 0·96, 0·65-1·41). In the four studies with mortality data, BCG vaccination was significantly protective against death (0·25, 0·13-0·49).
INTERPRETATION
Our results suggest that BCG vaccination at birth is effective at preventing tuberculosis in young children but is ineffective in adolescents and adults. Immunoprotection therefore needs to be boosted in older populations.
FUNDING
National Institutes of Health.
Topics: Adolescent; Adult; Aged; BCG Vaccine; Child; Child, Preschool; Humans; Infant; Infant, Newborn; Retrospective Studies; Tuberculosis; Tuberculosis, Pulmonary; Vaccination
PubMed: 35961354
DOI: 10.1016/S2214-109X(22)00283-2 -
PloS One Apr 2011The prognosis, specifically the case fatality and duration, of untreated tuberculosis is important as many patients are not correctly diagnosed and therefore receive... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The prognosis, specifically the case fatality and duration, of untreated tuberculosis is important as many patients are not correctly diagnosed and therefore receive inadequate or no treatment. Furthermore, duration and case fatality of tuberculosis are key parameters in interpreting epidemiological data.
METHODOLOGY AND PRINCIPAL FINDINGS
To estimate the duration and case fatality of untreated pulmonary tuberculosis in HIV negative patients we reviewed studies from the pre-chemotherapy era. Untreated smear-positive tuberculosis among HIV negative individuals has a 10-year case fatality variously reported between 53% and 86%, with a weighted mean of 70%. Ten-year case fatality of culture-positive smear-negative tuberculosis was nowhere reported directly but can be indirectly estimated to be approximately 20%. The duration of tuberculosis from onset to cure or death is approximately 3 years and appears to be similar for smear-positive and smear-negative tuberculosis.
CONCLUSIONS
Current models of untreated tuberculosis that assume a total duration of 2 years until self-cure or death underestimate the duration of disease by about one year, but their case fatality estimates of 70% for smear-positive and 20% for culture-positive smear-negative tuberculosis appear to be satisfactory.
Topics: Disease Progression; HIV Seronegativity; Humans; Survival Analysis; Time Factors; Tuberculosis, Pulmonary
PubMed: 21483732
DOI: 10.1371/journal.pone.0017601 -
EBioMedicine Aug 2019Breath tests may diagnose tuberculosis (TB) through detecting specific volatile organic compounds produced by Mycobacterium tuberculosis or the infected host. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Breath tests may diagnose tuberculosis (TB) through detecting specific volatile organic compounds produced by Mycobacterium tuberculosis or the infected host.
METHODS
To estimate the diagnostic accuracy of breath test with electronic-nose and other devices against culture or other tests for TB, we screened multiple databases until January 6, 2019.
FINDINGS
We included fourteen studies, with 1715 subjects in the analysis. The pooled sensitivity and specificity of electronic-nose were 0.93 (95% CI 0.82-0.97) and 0.93 (95% CI 0.82-0.97), respectively, and no heterogeneity was found. The sensitivity and specificity of other breath test devices ranged from 0.62 to 1.00, and 0.11 to 0.84, respectively.
INTERPRETATION
The low to moderate evidence of these studies shows that breath tests can diagnose TB accurately, however, to give a real-time test result, additional development is needed. Research should also focus on sputum smear negative TB, children, and the positioning of breath testing in the diagnostic work flow.
FUNDING
The authors received no specific funding for this work.
Topics: Biosensing Techniques; Breath Tests; Electronic Nose; Female; Humans; Male; Mycobacterium tuberculosis; ROC Curve; Reproducibility of Results; Sensitivity and Specificity; Tuberculosis; Tuberculosis, Pulmonary; Volatile Organic Compounds
PubMed: 31401197
DOI: 10.1016/j.ebiom.2019.07.056 -
The Indian Journal of Medical Research 2023The National Prevalence Survey of India (2019-2021) estimated 31 per cent tuberculosis infection (TBI) burden among individuals above 15 years of age. However, so far... (Meta-Analysis)
Meta-Analysis
BACKGROUND & OBJECTIVES
The National Prevalence Survey of India (2019-2021) estimated 31 per cent tuberculosis infection (TBI) burden among individuals above 15 years of age. However, so far little is known about the TBI burden among the different risk groups in India. Thus, this systematic review and meta-analysis, aimed to estimate the prevalence of TBI in India based on geographies, sociodemographic profile, and risk groups.
METHODS
To identify the prevalence of TBI in India, data sources such as MEDLINE, EMBASE, CINAHL, and Scopus were searched for articles reporting data between 2013-2022, irrespective of the language and study setting. TBI data were extracted from 77 publications and pooled prevalence was estimated from the 15 community-based cohort studies. Articles were reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and were sourced using a predefined search strategy from different databases.
RESULTS
Out of 10,521 records, 77 studies (46 cross-sectional and 31 cohort studies) were included. The pooled TBI prevalence for India based on the community-based cohort studies was estimated as 41 per cent [95% confidence interval (CI) 29.5-52.6%] irrespective of the risk of acquiring it, while the estimation was 36 per cent (95% CI 28-45%) prevalence observed among the general population excluding high-risk groups. Regions with high active TB burden were found to have a high TBI prevalence such as Delhi and Tamil Nadu. An increasing trend of TBI was observed with increasing age in India.
INTERPRETATION & CONCLUSIONS
This review demonstrated a high prevalence of TBI in India. The burden of TBI was commensurate with active TB prevalence suggesting possible conversion of TBI to active TB. A high burden was recorded among people residing in the northern and southern regions of the country. Such local epidemiologic variation need to be considered to reprioritize and implement-tailored strategies for managing TBI in India.
Topics: Humans; Prevalence; India; Cross-Sectional Studies; Tuberculosis; Latent Tuberculosis
PubMed: 37202933
DOI: 10.4103/ijmr.ijmr_382_23