Burden of tuberculosis among vulnerable populations worldwide: an overview of systematic reviews

Research priorities and trends in pulmonary tuberculosis in Latin America: A bibliometric analysis

Tuberculosis (TB) poses a significant global public health challenge, particularly in developing countries. Over the years, scientific research has played a pivotal role in addressing this disease. In this study, we aimed to analyze and outline the trends in scientific output on TB and identify research priorities in Latin America (LA) from 1990 to 2021. Scientific production was analyzed, and the number of publications, financing sources, and journal characteristics were evaluated. Collaboration networks and keywords were visualized using mapping analysis with VOSviewer software. Research themes were prioritized by country based on co-occurrence frequency. In total, 4399 documents were identified, a significant trend was evident in the number of publications per year (R2 = 0.981), and research substantially contributed to the reduction of TB-related mortality (R2 = -0.876). Most publications were original articles (83.8 %). The International Journal of Tuberculosis and Lung Disease had the highest publication and citation rates per document. International collaboration was predominantly with the United States, France, and Canada. Brazil, Argentina, and Mexico had the highest number of publications and external collaborations. In LA, interest in researching studies related to treatment and diagnosis (32.5 %) was notably high, followed by epidemiology and screening (26.9 %). Among the 20 countries in LA, research priorities varied, with the highest emphasis on HIV/AIDS (14/20), epidemiology (9/20), anti-TB agents (6/20), and mortality (5/20). TB resistance was only considered a research priority in Brazil, Peru, and Haiti. Therefore, LA experienced significant growth in its scientific output, playing a crucial role in TB control. Strategic adaptation to the region's specific challenges was observed, particularly in HIV/AIDS coinfection, epidemiological studies, and drug resistance. This progress was achieved by outstanding international scientific collaboration. This holistic approach emphasizes the importance of research in the fight against TB in LA.

For Tuberculosis, Not "To Screen or Not to Screen?" but "Who?" and "How?"

Active case finding leveraging new molecular diagnostics and chest X-rays with automated interpretation algorithms is increasingly being developed for high-risk populations to drive down tuberculosis incidence. We consider why such an approach did not deliver a decline in tuberculosis prevalence in Brazilian prison populations and what to consider next.

The effect of conditional cash transfers on tuberculosis incidence and mortality is determined by ethnoracial and socioeconomic factors: a cohort study of 54 million individuals in Brazil

Background

Conditional Cash Transfers (CCT) are the world's most widely implemented interventions for poverty alleviation. Still, there is no solid evidence of the CCT effects on the reduction of the burden of Tuberculosis (TB) in marginalized and extremely vulnerable populations. We estimated the effect of the Bolsa Família Program (BFP), the largest CCT in the world, on TB incidence, mortality, and case-fatality rate using a nationwide cohort of 54.5 million individuals during a 12-year period in Brazil.

Methods

We selected low-income individuals who entered in the 100 Million Brazilians Cohort and were linked to nationwide TB registries between 2004 to 2015, and compared BFP beneficiaries and non-beneficiaries using a quasi-experimental impact evaluation design. We employed inverse probability of treatment weighting (IPTW) multivariable Poisson regressions, adjusted for all relevant socioeconomic, demographic, and healthcare confounding variables - at individual and municipal level. Subsequently, we evaluated BFP effects for different subpopulations according to ethnoracial factors, wealth levels, sex, and age. We also performed several sensitivity and triangulation analyses to verify the robustness of the estimates.

Findings

Exposure to BFP was associated with a large reduction in TB incidence in the low-income individuals under study (adjusted rate ratio [aRR]:0.59;95%CI:0.58-0.60) and mortality (aRR:0.69;95%CI:0.65-0.73). The strongest BFP effect was observed in Indigenous people both for TB incidence (aRR:0.37;95%CI:0.32-0.42), and mortality-aRR:0.35;95%CI:0.20-0.62), and in Black and Pardo people (Incidence-aRR:0.58;95%CI:0.57-0.59; Mortality -aRR:0.69;95%CI:0,64-0,73). BFP effects showed a clear gradient according to wealth levels and were considerably stronger among the extremely poor individuals for TB incidence (aRR:0.49, 95%CI:0.49-0.50) and mortality (aRR:0.60;95%CI:0.55-0.65). The BFP effects on case-fatality rates were also positive, however without statistical significance.

Interpretation

CCT can strongly reduce TB incidence and mortality in extremely poor, Indigenous, Black and Pardo populations, and could significantly contribute to achieving the End TB Strategy targets and the TB-related Sustainable Development Goals.

Tuberculosis prevalence and demographic characteristics of population in Azad Jammu and Kashmir (Pakistan): A retrospective study

Tuberculosis (TB) remains a serious problem for public health and a leading cause of death after COVID-19 and superior to even HIV/AIDS. It is a social health issue and can cause stigma and economic loss as the person cannot perform professionally due to lethargy caused by disease. It is a retrospective study done on data from National TB program Muzaffarabad chapter. The details were noted on SPSS and analysis was done to find important demographic characteristics. The total number of patients was 3441; among which 48.76% were males. Most of them (81.11%) belonged to the Muzaffarabad division of Azad Jammu and Kahmir (AJK). The microbiologically or culture positive cases were 440. Rifampicin resistance was present in 147 cases, further categorized as high (n = 143), very high (n = 3), or true positive (n = 1) resistance. Muti drug resistance was found in 19 cases. The microscopy culture is more sensitive (AUC = 0.511) than MTB/RIF or serology (AUC = 0.502) according to ROC. The rate of positive smear results is not very satisfactory in the present study as it cannot detect dormant or latent cases. There is a need to establish more sensitive tests for detection of cases and more research to combat the disease.

Screening for latent tuberculosis in migrants-status quo and future challenges

OBJECTIVES

To review the evidence that migrants from tuberculosis (TB) high-incidence countries migrating to TB low-incidence countries significantly contribute to active TB cases in the counties of destination, primarily through reactivation of latent TB.

METHODS

This is a narrative review. The different screening programs in the countries of destination are reviewed either based on screening and preventive treatment of latent TB pre or more commonly - post arrival.

RESULTS

Screening can be performed using interferon-gamma release assays (IGRA) or tuberculin skin tests (TST). Preventive treatment of latent TB is using either monotherapy with isoniazid, or in combination with rifampicin or rifapentine. We discuss the ethical issues of preventive treatment in asymptomatic individuals and how these are addressed in different screening programs.

CONCLUSION

Screening migrants from TB high endemic countries to TB low endemic countries is beneficial. There is a lack of standardization and agreement on screening protocols, follow up and treatment.

Engagement of private health care facilities in TB management in Lusaka district of Zambia: lessons learned and achievements

BACKGROUND

Globally, at least 3 million TB patients are missed every year. In Zambia, the TB treatment coverage increased from 66% in 2020 to 92% in 2022. Involvement of all levels of health care service delivery is critical to finding all the missing TB patients.

METHODS

A survey was undertaken in 15 private facilities in Lusaka district of Zambia using a structured tool administered by project team and a district health team member. Data collected during the survey was analysed and results were used to determine the type of TB services that were offered as well as barriers and enablers to TB service provision. This was followed by a set of interventions that included; training and mentorship on active case finding and systematic TB screening, increased diagnostic capacity, provision of national recording and reporting tools and provision of TB medication through linkage with the National TB program (NTP). We report findings from the baseline survey and changes in presumptive TB identification and notification following interventions.

RESULTS

Major barriers to TB service delivery were the high cost of TB diagnostic testing and treatment in facilities where services were not supported by the National TB program; the mean cost was 33 (SD 33) and 93 (SD 148) for GeneXpert testing and a full course of treatment respectively. Pre-intervention, presumptive TB identification appeared to increase monthly by 4 (P = 0.000, CI=[3.00-5.00]). The monthly trends of presumptive TB identification during the intervention period increased by 5.32 (P = 0.000, [CI 4.31-6.33. Pre-intervention, the notification of TB appeared to decrease every month by -4.0 (P = 0.114, CI=[-9.00-0.10]) followed by an immediate increase in notifications of 13.94 TB patients (P = 0.001, CI [6.51, 21.36] in the first month on intervention. The monthly trends of notification during the intervention period changed by 0.34 (P = 0.000 [CI 0.19-0.48]). Private facility contribution to TB notification increased from 3 to 7%.

CONCLUSION

Engagement and inclusion of private health facilities in TB service provision through a systems strengthening approach can increase contribution to TB notification by private health facilities.

Interventions to improve latent and active tuberculosis treatment completion rates in underserved groups in low incidence countries: a scoping review

BACKGROUND

People in underserved groups have higher rates of tuberculosis (TB) and poorer treatment outcomes compared with people with no social risk factors.

OBJECTIVES

This scoping review aimed to identify interventions that improve TB treatment adherence or completion rates.

ELIGIBILITY CRITERIA

Studies of any design focusing on interventions to improve adherence or completion of TB treatment in underserved populations in low incidence countries.

SOURCES OF EVIDENCE

MEDLINE, Embase and Cochrane CENTRAL were searched (January 2015 to December 2023).

CHARTING METHODS

Piloted data extraction forms were used. Findings were tabulated and reported narratively. Formal risk of bias assessment or synthesis was not undertaken.

RESULTS

47 studies were identified. There was substantial heterogeneity in study design, population, intervention components, usual care and definition of completion rates. Most studies were in migrants or refugees, with fewer in populations with other risk factors (eg, homelessness, imprisonment or substance abuse). Based on controlled studies, there was limited evidence to suggest that shorter treatment regimens, video-observed therapy (compared with directly observed therapy), directly observed therapy (compared with self-administered treatment) and approaches that include tailored health or social support beyond TB treatment may lead to improved outcomes. This evidence is mostly observational and subject to confounding. There were no studies in Gypsy, Roma and Traveller populations, or individuals with mental health disorders and only one in sex workers. Barriers to treatment adherence included a lack of knowledge around TB, lack of general health or social support and side effects. Facilitators included health education, trusted relationships between patients and healthcare staff, social support and reduced treatment duration.

CONCLUSIONS

The evidence base is limited, and few controlled studies exist. Further high-quality research in well-defined underserved populations is needed to confirm the limited findings and inform policy and practice in TB management. Further qualitative research should include more people from underserved groups.

Prevalence and Spatial Autocorrelation of Tuberculosis in Indigenous People in Brazil, 2002-2022

Tuberculosis (TB) among indigenous populations in Brazil poses a multifaceted public health challenge influenced by geographical, social, institutional, economic, and cultural factors. This study scrutinized the prevalence and spatial distribution of TB among Brazilian indigenous communities from 2002 to 2022. Employing a cross-sectional and descriptive approach, we analyzed data from the Notifiable Diseases Information System (SINAN) and conducted spatial autocorrelation tests to identify clusters and outliers. The findings uncovered substantial disparities in TB prevalence between the North and Central-West regions, in contrast to the South and Southeast, mirroring social, economic, and cultural inequalities in Brazil. It is concluded that public health strategies should not only consider the epidemiological aspects of TB but also encompass social and environmental determinants, notably the impact of climate change. Holistic and context-sensitive approaches are imperative for addressing TB within indigenous communities, underscoring the need for adaptive and culturally sensitive interventions in the public health landscape.