Passive case finding for tuberculosis is not enough

A mixed-methods study on impact of active case finding on pulmonary tuberculosis treatment outcomes in India

BACKGROUND

Tuberculosis (TB) remains a significant public health burden in India, with elimination targets set for 2025. Active case finding (ACF) is crucial for improving TB case detection rates, although conclusive evidence of its association with treatment outcomes is lacking. Our study aims to investigate the impact of ACF on successful TB treatment outcomes among pulmonary TB patients in Gujarat, India, and explore why ACF positively impacts these outcomes.

METHODS

We conducted a retrospective cohort analysis in Gujarat, India, including 1,638 pulmonary TB cases identified through ACF and 80,957 cases through passive case finding (PCF) from January 2019 to December 2020. Generalized logistic mixed-model compared treatment outcomes between the ACF and PCF groups. Additionally, in-depth interviews were conducted with 11 TB program functionaries to explore their perceptions of ACF and its impact on TB treatment outcomes.

RESULTS

Our analysis revealed that patients diagnosed through ACF exhibited 1.4 times higher odds of successful treatment outcomes compared to those identified through PCF. Program functionaries emphasized that ACF enhances case detection rates and enables early detection and prompt treatment initiation. This early intervention facilitates faster sputum conversion and helps reduce the infectious period, thereby improving treatment outcomes. Functionaries highlighted that ACF identifies TB cases that might otherwise be missed, ensuring timely and appropriate treatment.

CONCLUSION

ACF significantly improves TB treatment outcomes in Gujarat, India. The mixed-methods analysis demonstrates a positive association between ACF and successful TB treatment, with early detection and prompt treatment initiation being key factors. Insights from TB program functionaries underscore the importance of ACF in ensuring timely diagnosis and treatment, which are critical for better treatment outcomes. Expanding ACF initiatives, especially among hard-to-reach populations, can further enhance TB control efforts. Future research should focus on optimizing ACF strategies and integrating additional interventions to sustain and improve TB treatment outcomes.

In-home TB Testing Using GeneXpert Edge is Acceptable, Feasible, and Improves the Proportion of Symptomatic Household Contacts Tested for TB: A Proof-of-Concept Study

Background

Household contact investigations are effective for finding tuberculosis (TB) cases but are hindered by low referral uptake for clinic-based evaluation and testing. We assessed the acceptability and feasibility of in-home testing of household contacts (HHC) using the GeneXpert Edge platform.

Methods

We conducted a 2-arm, randomized study in Eastern Cape, South Africa. HHCs were verbally assessed using the World Health Organization-recommended 4-symptom screen. Households with ≥1 eligible symptomatic contact were randomized. Intervention households received in-home GeneXpert MTB/RIF molecular testing. GeneXpert-positive HHCs were referred for clinic-based treatment. Standard-of-care households were referred for clinic-based sputum collection and testing. We defined acceptability as agreeing to in-home testing and feasibility as generation of valid Xpert MTB/RIF results. The proportion and timeliness of test results received was compared between groups.

Results

Eighty-four households were randomized (n = 42 per arm). Of 100 eligible HHCs identified, 98/100 (98%) provided consent. Of 51 HHCs allocated to the intervention arm, all accepted in-home testing; of those, 24/51 (47%) were sputum productive and 23/24 (96%) received their test results. Of 47 HCCs allocated to standard-of-care, 7 (15%) presented for clinic-based TB evaluation, 6/47 (13%) were tested, and 4/6 (67%) returned for their results. The median (interquartile range) number of days from screening to receiving test results was 0 (0) and 16.5 (11-15) in the intervention and standard-of-care arms, respectively.

Conclusions

In-home testing for TB was acceptable, feasible, and increased HHCs with a molecular test result. In-home testing mitigates a major limitation of household contact investigations (dependency on clinic-based referral), revealing new strategies for enhancing early case detection.

Association between TB delay and TB treatment outcomes in HIV-TB co-infected patients: a study based on the multilevel propensity score method

BACKGROUND

HIV-tuberculosis (HIV-TB) co-infection is a significant public health concern worldwide. TB delay, consisting of patient delay, diagnostic delay, treatment delay, increases the risk of adverse anti-TB treatment (ATT) outcomes. Except for individual level variables, differences in regional levels have been shown to impact the ATT outcomes. However, few studies appropriately considered possible individual and regional level confounding variables. In this study, we aimed to assess the association of TB delay on treatment outcomes in HIV-TB co-infected patients in Liangshan Yi Autonomous Prefecture (Liangshan Prefecture) of China, using a causal inference framework while taking into account individual and regional level factors.

METHODS

We conducted a study to analyze data from 2068 patients with HIV-TB co-infection in Liangshan Prefecture from 2019 to 2022. To address potential confounding bias, we used a causal directed acyclic graph (DAG) to select appropriate confounding variables. Further, we controlled for these confounders through multilevel propensity score and inverse probability weighting (IPW).

RESULTS

The successful rate of ATT for patients with HIV-TB co-infection in Liangshan Prefecture was 91.2%. Total delay (OR = 1.411, 95% CI: 1.015, 1.962), diagnostic delay (OR = 1.778, 95% CI: 1.261, 2.508), treatment delay (OR = 1.749, 95% CI: 1.146, 2.668) and health system delay (OR = 1.480 95% CI: (1.035, 2.118) were identified as risk factors for successful ATT outcome. Sensitivity analysis demonstrated the robustness of these findings.

CONCLUSIONS

HIV-TB co-infection prevention and control policy in Liangshan Prefecture should prioritize early treatment for diagnosed HIV-TB co-infected patients. It is urgent to improve the health system in Liangshan Prefecture to reduce delays in diagnosis and treatment.

Tuberculosis Case Finding in Kulon Progo District, Yogyakarta, Indonesia: Passive versus Active Case Finding Using Mobile Chest X-ray

Active-case finding (ACF) using chest X-ray is an essential method of finding and diagnosing Tuberculosis (TB) cases that may be missed in Indonesia's routine TB case finding. This study compares active and passive TB case-finding strategies. A retrospective study of TB case notification was conducted. Data between 1 January and 31 December 2021, was used. The population in this study were TB cases notified from Kulon Progo District health facilities, including those found through routine activities or active-case findings. A total of 249 TB cases were diagnosed in Kulon Progo in 2021, and 102 (41%) were bacteriologically confirmed. The TB patients' ages ranged from 0 to 85 years (median 52, IQR 31-61). The majority of cases were male (59%, 147/249) and mostly among people aged 15-59 (61.4%, 153/249). The proportion of clinical TB diagnoses among cases found from active-case findings was 74.7% (68/91) while the proportion among passive-case findings was 50% (79/158). Active-case finding contributed 91 (36.5%) TB cases to the total cases detected in Kulon Progo in 2021. The use of chest X-rays in active-case findings likely contributed to the detection of a higher proportion of clinical TB than in passive-case findings.

Quality of active case-finding for tuberculosis in India: a national level secondary data analysis

BACKGROUND

India has been implementing active case-finding (ACF) for TB among marginalised and vulnerable (high-risk) populations since 2017. The effectiveness of ACF cycle(s) is dependent on the use of appropriate screening and diagnostic tools and meeting quality indicators.

OBJECTIVES

To determine the number of ACF cycles implemented in 2021 at national, state (n = 36) and district (n = 768) level and quality indicators for the first ACF cycle.

METHODS

In this descriptive study, aggregate TB program data for each ACF activity that was extracted was further aggregated against each ACF cycle at the district level in 2021. One ACF cycle was the period identified to cover all the high-risk populations in the district. Three TB ACF quality indicators were calculated: percentage population screened (≥10%), percentage tested among screened (≥4.8%) and percentage diagnosed among tested (≥5%). We also calculated the number needed to screen (NNS) for diagnosing one person with TB (≤1538).

RESULTS

Of 768 TB districts, ACF data for 111 were not available. Of the remaining 657 districts, 642 (98%) implemented one, and 15 implemented two to three ACF cycles. None of the districts or states met all three TB ACF quality indicators' cut-offs. At the national level, for the first ACF cycle, 9.3% of the population were screened, 1% of the screened were tested and 3.7% of the tested were diagnosed. The NNS was 2824: acceptable (≤1538) in institutional facilities and poor for population-based groups. Data were not consistently available to calculate the percentage of i) high-risk population covered, ii) presumptive TB among screened and iii) tested among presumptive.

CONCLUSION

In 2021, India implemented one ACF cycle with sub-optimal ACF quality indicators. Reducing the losses between screening and testing, improving data quality and sensitising stakeholders regarding the importance of meeting all ACF quality indicators are recommended.

Mass Tuberculosis Screening Among the Elderly: A Population-Based Study in a Well-Confined, Rural County in Eastern China

BACKGROUND

Mass tuberculosis (TB) screening has been recommended in certain high-risk populations. However, population-based screening interventions have rarely been implemented. Whether mass screening improves health equity is unknown.

METHODS

We implemented a mass TB screening intervention among elderly persons (>60 years old) in Lanxi County, China. Standardized questionnaires, physical examinations, and chest radiographs (CXRs) were administered to all participants. Systematic testing with computed tomography, smear, culture, or Xpert was performed among persons with an abnormal CXR. We assessed TB prevalence per 100 000 persons and constructed multivariable regression models among subgroups that were and were not screened. Medical insurance was categorized as participation in either a basic program with limited coverage or a more comprehensive coverage program.

RESULTS

In total, 49 339 individuals (32% of the elderly population in Lanxi) participated in the screening. One hundred fifteen screened persons were diagnosed with TB (233 cases per 100 000 persons), significantly higher than persons not screened (168 cases among 103 979 person-years; prevalence-to-case notification ratio, 1.44 [95% confidence interval {CI}, 1.14-1.83]). This increase was largely driven by diagnosis of asymptomatic disease during mass screening (n = 57 [50% of participants with TB]). Participants with basic medical insurance were much more likely to be diagnosed through mass screening than by passive detection (adjusted odds ratio, 4.52 [95% CI, 1.35-21.28]).

CONCLUSIONS

In a population-based, mass TB screening intervention encompassing >30% of the elderly population in a county in rural China, case finding was 44% higher than background detection, driven by diagnosis of TB without recognized symptoms. Importantly, mass screening identified TB in people with limited healthcare options who were less likely to be found through background case detection.

Finding and treating both tuberculosis disease and latent infection during population-wide active case finding for tuberculosis elimination

In recognition of the high rates of undetected tuberculosis in the community, the World Health Organization (WHO) encourages targeted active case finding (ACF) among "high-risk" populations. While this strategy has led to increased case detection in these populations, the epidemic impact of these interventions has not been demonstrated. Historical data suggest that population-wide (untargeted) ACF can interrupt transmission in high-incidence settings, but implementation remains lacking, despite recent advances in screening tools. The reservoir of latent infection-affecting up to a quarter of the global population -complicates elimination efforts by acting as a pool from which future tuberculosis cases may emerge, even after all active cases have been treated. A holistic case finding strategy that addresses both active disease and latent infection is likely to be the optimal approach for rapidly achieving sustainable progress toward TB elimination in a durable way, but safety and cost effectiveness have not been demonstrated. Sensitive, symptom-agnostic community screening, combined with effective tuberculosis treatment and prevention, should eliminate all infectious cases in the community, whilst identifying and treating people with latent infection will also eliminate tomorrow's tuberculosis cases. If real strides toward global tuberculosis elimination are to be made, bold strategies are required using the best available tools and a long horizon for cost-benefit assessment.

The performance of tongue swabs for detection of pulmonary tuberculosis

Introduction

Oral and/or tongue swabs have demonstrated ability to detect Mycobacterium tuberculosis (Mtb) in adults with pulmonary tuberculosis (TB). Swabs provide useful alternative specimens for diagnosis of TB using molecular assays however, the diagnostic pickup by culture requires further improvement and development. Several studies identified the presence of differentially culturable tubercle bacilli (DCTB) populations in a variety of clinical specimens. These organisms do not grow in routine laboratory media and require growth factors in the form of culture filtrate (CF) from logarithmic phase cultures of Mtb H37Rv.

Methods

Herein, we compared the diagnostic performance of sputum and tongue swabs using Mycobacterial Growth Indicator Tube (MGIT) assays, Auramine smear, GeneXpert and DCTB assays supplemented with or without CF.

Results

From 89 eligible participants, 83 (93%), 66 (74%) and 79 (89%) were sputum positive by MGIT, smear and GeneXpert, respectively. The corresponding tongue swabs displayed a lower sensitivity with 39 (44%), 2 (2.0%) and 18 (20%) participants respectively for the same tests. We aimed to improve the diagnostic yield by utilizing DCTB assays. Sputum samples were associated with a higher positivity rate for CF-augmented DCTB at 82/89 (92%) relative to tongue swabs at 36/89 (40%). Similarly, sputum samples had a higher positivity rate for DCTB populations that were CF-independent at 64/89 (72%) relative to tongue swabs at 26/89 (29%). DCTB positivity increased significantly, relative to MGIT culture, for tongue swabs taken from HIV-positive participants. We next tested whether the use of an alternative smear stain, DMN-Trehalose, would improve diagnostic yield but noted no substantial increase.

Discussion

Collectively, our data show that while tongue swabs yield lower bacterial numbers for diagnostic testing, the use of growth supplementation may improve detection of TB particularly in HIV-positive people but this requires further interrogation in larger studies.

Facilitators and barriers to tuberculosis active case findings in low- and middle-income countries: a systematic review of qualitative research

BACKGROUND

Tuberculosis (TB) is an ancient infection and a major public health problem in many low- and middle-income countries (LMICs). Active case finding (ACF) programs have been established to effectively reduce TB in endemic global communities. However, there is little information about the evidence-based benefits of active case finding at both the individual and community levels. Accurately identifying the facilitators and barriers to TB-ACF provides information that can be used in planning and design as the world aims to end the global TB epidemic by 2035. Therefore, this study aimed to identify the facilitators and barriers to tuberculosis ACF in LMICs.

METHODS

A systematic search was performed using recognized databases such as PubMed, Google Scholar, SCOPUS, HINARI, and other reference databases. Relevant studies that assessed or reported the ACF of TB conducted in LMICs were included in this study. The Joanna Briggs Institute's (JBI) Critical Appraisal Tool was used to assess the quality of the selected studies. The Statement of Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) was used to strengthen the protocol for this systematic review. The Confidence of Evidence Review Quality (CERQual) approach was also used to assess the reliability of the review findings.

RESULTS

From 228 search results, a total of 23 studies were included in the final review. Tuberculosis ACF results were generated under two main themes: barriers and facilitators in LMICs, and two sub-themes of the barriers (healthcare-related and non-healthcare-related barriers). Finally, barriers to active TB case finding were found to be related to (1) the healthcare workers' experience, knowledge, and skills in detecting TB-ACF, (2) distance and time; (3) availability and workload of ACF healthcare workers; (4) barriers related to a lack of resources such as diagnostic equipment, reagents, and consumables at TB-ACF; (5) the stigma associated with TB-ACF detection; (6) the lack of training of existing and new healthcare professionals to detect TB-ACF; (7) communication strategies and language limitations associated with TB ACF; and (8) poor or no community awareness of tuberculosis. Stigma was the most patient-related obstacle to detecting active TB cases in LMICs.

CONCLUSION

This review found that surveillance, monitoring, health worker training, integration into health systems, and long-term funding of health facilities were key to the sustainability of ACF in LMICs. Understanding the elimination of the identified barriers is critical to ensuring a maximum tuberculosis control strategy through ACF.

Comparing Additionality of Tuberculosis Cases Using GeneXpert or Smear-Based Active TB Case-Finding Strategies among Social Contacts of Index Cases in Nepal

This study compares the yield and additionality of community-based active tuberculosis (TB) active case-finding strategies using either smear microscopy or GeneXpert as the TB diagnostic test. Active case-finding strategies screened social contacts of index cases and high-risk groups in four districts of Nepal in July 2017-2019. Two districts (Chitwan and Dhanusha) applied GeneXpert testing and two districts (Makwanpur and Mahotarri) used smear microscopy. Two control districts implemented standard national TB program activities. Districts implementing GeneXpert testing screened 23,657 people for TB, tested 17,114 and diagnosed 764 TB cases, producing a yield of 4.5%. Districts implementing smear microscopy screened 19,961 people for TB, tested 13,285 and diagnosed 437 cases, producing a yield of 3.3%. The screening numbers required were 31 for GeneXpert and 45.7 for smear districts. The test numbers required were 22.4 and 30.4 for GeneXpert and smear. Using the TB REACH additionality method, social contact tracing for TB through GeneXpert testing contributed to a 20% (3958/3322) increase in district-level TB notifications, smear microscopy 12.4% (3146/2798), and -0.5% (2553/2566) for control districts. Therefore, social contact tracing of TB index cases using GeneXpert testing should be implemented throughout Nepal within the TB FREE initiative to close the notification gap and accelerate progress toward END TB strategy targets.

Economic evaluation of a community health worker model for tuberculosis care in Ho Chi Minh City, Viet Nam: a mixed-methods Social Return on Investment Analysis

BACKGROUND

There is extensive evidence for the cost-effectiveness of programmatic and additional tuberculosis (TB) interventions, but no studies have employed the social return on investment (SROI) methodology. We conducted a SROI analysis to measure the benefits of a community health worker (CHW) model for active TB case finding and patient-centered care.

METHODS

This mixed-method study took place alongside a TB intervention implemented in Ho Chi Minh City, Viet Nam, between October-2017 - September-2019. The valuation encompassed beneficiary, health system and societal perspectives over a 5-year time-horizon. We conducted a rapid literature review, two focus group discussions and 14 in-depth interviews to identify and validate pertinent stakeholders and material value drivers. We compiled quantitative data from the TB program's and the intervention's surveillance systems, ecological databases, scientific publications, project accounts and 11 beneficiary surveys. We mapped, quantified and monetized value drivers to derive a crude financial benefit, which was adjusted for four counterfactuals. We calculated a SROI based on the net present value (NPV) of benefits and investments using a discounted cash flow model with a discount rate of 3.5%. A scenario analysis assessed SROI at varying discount rates of 0-10%.

RESULTS

The mathematical model yielded NPVs of US$235,511 in investments and US$8,497,183 in benefits. This suggested a return of US$36.08 for each dollar invested, ranging from US$31.66-US39.00 for varying discount rate scenarios.

CONCLUSIONS

The evaluated CHW-based TB intervention generated substantial individual and societal benefits. The SROI methodology may be an alternative for the economic evaluation of healthcare interventions.

High non-compliance rate among presumptive tuberculosis cases referred from peripheral health facilities in silti district of Southern Ethiopia: a mixed methods study

BACKGROUND

For presumptive Tuberculosis (TB) case referral to be effective, most of the referred cases need to present themselves to health facilities for assessment and testing. Otherwise, cases of TB could be missed, and these cases are at an increased risk of delayed diagnosis, complications and death. Further, their care incurs significantly higher costs. This study assessed referral compliance as well as factors attributable to compliance/non-compliance to referral of presumptive TB cases in Silti district, Southern Ethiopia.

METHOD

We applied a mixed design involving both quantitative and qualitative methods. A randomly selected sample of 384 presumptive TB cases referred between January, 2014 and July 2021 were included in this study from the records of 12 health posts. Purposefully selected presumptive TB cases and Health Extension Workers were also interviewed to get in-depth information on the reasons for compliance and non-compliance to referral. STATA version 14 was employed to model the data using logistic regression. Qualitative data were analyzed using thematic content analysis.

RESULTS

Of the 384 referred presumptive TB cases, close to 49% did not present themselves to the referral facilities. About 66% (n = 249) of the referred cases were women, and 62% (n = 119) of those who complied to referral were women. In multivariate analysis, cough [AOR = 3.4, 95%CI: 1.54-7.32], and chest pain [AOR = 2.7, 95%CI: 1.45-5.05] were independent predictors of compliance to referral. Nearly 5.5% (n = 21) of TB cases of all types were identified. The qualitative data analysis revealed that severe disease symptoms, HEW's recommendations, and social issues as reasons improving compliance while personal and social factors, financial problems, lack of awareness about TB and transportation were reasons impeding compliance to referral.

CONCLUSION

Our study showed a high level of non-compliance to referral among referred presumptive TB cases. We also found that more women were referred and also complied with the referral. Strengthening community awareness about the disease symptoms and the existence of free treatment, addressing misconceptions about TB, supporting the elderly and disabled, and checkup house visits after referral could improve compliance to referral.

Where are the missing people affected by tuberculosis? A programme review of patient-pathway and cascade of care to optimise tuberculosis case-finding, treatment and prevention in Cambodia

BACKGROUND

Cambodia has achieved great success in tuberculosis (TB) control in the past decade. Nevertheless, people with TB are missed by the health systems at different stages of the care pathway. This programme review corroborated the care-seeking behaviours of people with TB and TB services availability and estimated the number of people completing each step of the TB disease and TB preventive treatment (TPT) care cascade.

METHODS

Patient pathways and the care cascades for TB disease and TPT were constructed using data from the latest national TB prevalence survey, routine surveillance and programme, the global TB database and published studies. We also randomly selected TB survivors in the 2019 cohort to assess recurrence-free survival 1-year post-treatment. TPT care cascade was constructed for people living with HIV (PLHIV) and household contacts (children <5 years and all ages) of persons with bacteriologically-confirmed TB in 2019 and 2020.

RESULTS

Nationally, 54% of those who exhibited TB symptoms sought initial care in the private sector. Overall, 93% and 58% of people with presumptive TB did not access a facility with TB diagnostic and treatment services, respectively, at the first point of care-seeking. Approximately 56% (95% CI 52% to 57%) of the 47 000 (95% CI 31 000 to 68 000) estimated TB cases in 2019 achieved recurrence-free survival. Among the estimated PLHIV in Cambodia, <30% completed TPT. Among children <5 years, 53% (95% CI 29% to 65%) (2019) and 67% (95% CI 36% to 80%) (2020) of those eligible for TPT completed the regimen successfully. In 2019 and 2020, 23% (95% CI 22% to 25%) and 54% (95% CI 50% to 58%) of the estimated household contacts (all ages) eligible for TPT completed the regimen successfully.

CONCLUSION

There are significant gaps in care-seeking, coverage and access to TB services and TPT in Cambodia. Action plans to improve TB response have been co-developed with local stakeholders to address the gaps throughout the care cascades.

A spatial analysis of TB cases and abnormal X-rays detected through active case-finding in Karachi, Pakistan

Tuberculosis (TB) is the leading cause of avoidable deaths from an infectious disease globally and a large of number of people who develop TB each year remain undiagnosed. Active case-finding has been recommended by the World Health Organization to bridge the case-detection gap for TB in high burden countries. However, concerns remain regarding their yield and cost-effectiveness. Data from mobile chest X-ray (CXR) supported active case-finding community camps conducted in Karachi, Pakistan from July 2018 to March 2020 was retrospectively analyzed. Frequency analysis was carried out at the camp-level and outcomes of interest for the spatial analyses were mycobacterium TB positivity (MTB+) and X-ray abnormality rates. The Global Moran's I statistic was used to test for spatial autocorrelation for MTB+ and abnormal X-rays within Union Councils (UCs) in Karachi. A total of 1161 (78.1%) camps yielded no MTB+ cases, 246 (16.5%) camps yielded 1 MTB+, 52 (3.5%) camps yielded 2 MTB+ and 27 (1.8%) yielded 3 or more MTB+. A total of 79 (5.3%) camps accounted for 193 (44.0%) of MTB+ cases detected. Statistically significant clustering for MTB positivity (Global Moran's I: 0.09) and abnormal chest X-rays (Global Moran's I: 0.36) rates was identified within UCs in Karachi. Clustering of UCs with high MTB positivity were identified in Karachi West district. Statistically significant spatial variation was identified in yield of bacteriologically positive TB cases and in abnormal CXR through active case-finding in Karachi. Cost-effectiveness of active case-finding programs can be improved by identifying and focusing interventions in hotspots and avoiding locations with no known TB cases reported through routine surveillance.

Beyond patient delay, navigating structural health system barriers to timely care and treatment in a high burden TB setting in Papua New Guinea

Tuberculosis (TB) is a major public health issue in Papua New Guinea, with incidence rates particularly high in the South Fly District of Western Province. We present three case studies, along with additional vignettes, that were derived from interviews and focus groups carried out between July 2019 and July 2020 of people living in rural areas of the remote South Fly District depicting their challenges accessing timely TB diagnosis and care; most services within the district are only offered offshore on Daru Island. The findings detail that rather than 'patient delay' attributed to poor health seeking behaviours and inadequate knowledge of TB symptoms, many people were actively trying to navigate structural barriers hindering access to and utilisation of limited local TB services. The findings highlight a fragile and fragmented health system, a lack of attention given to primary health services, and undue financial burdens placed on people living in rural and remote areas associated with costly transportation to access functioning health services. We conclude that a person-centred and effective decentralised model of TB care as outlined in health policies is imperative for equitable access to essential health care services in Papua New Guinea.

A symptomatic approach to tuberculosis screening for high-risk groups in Malaysia: Cost-effectiveness and budget impact analysis

BACKGROUND

One of the crucial areas of eliminating TB is the early detection of cases through the screening programme. This study's focal point is to measure the relative cost-effectiveness and budget impact of the symptomatic approach compared to the existing approach of TB screening (consisted of both symptomatic and asymptomatic screening) among high-risk groups in Malaysia.

METHOD

The Cost-Effectiveness Analysis (CEA) was measured using a decision tree model and the outcome is presented in terms of cost per TB case detected and the ICER. Analysis was conducted using secondary data collected from the Disease Control Division, Sabah and Sarawak State Health Departments. The robustness of the model is determined by Deterministic and Probabilistic Sensitivity Analysis. Subsequently, Budget impact over 5 years period, from 2018 to 2022 was estimated for both approaches.

RESULTS

The symptomatic approach was more cost-effective than the existing approach with ICER of MYR 424.71. The cost of conducting Sputum for Acid Fast Bacilli (SAFB) was found as the key driver for ICER. Budget Impact Analysis showed that switching from the existing approach towards the symptomatic approach would result in a cost-saving of MYR 65.5 million over 5 years. However, this would lead to 4473 TB cases being undetected over the same duration.

CONCLUSION

This study suggests that the policymakers have to weigh the trade-off between cost-saving and TB case detection. This cost-saving can be channelled to new TB intervention programme with a higher chance of TB case detection. Nevertheless, any decision made must be in concordance to the objectives of the country's TB programme.

Molecular genetic tests GeneXpert MTB/RIF and Xpert MTB/RIF (Ultra) in the diagnosis of tuberculosis (review of literature)

In recent tuberculosis years is the main cause of morbidity and death among patients with HIV infection. Modern diagnostics of tuberculosis includes mass screening of the population: digital fluorography from the age of 15 and immunodiagnostics in children and adolescents. Detection of mycobacterium tuberculosis by microscopy occurs in forms of tuberculosis with the decay of lung tissue. Such patients represent a high epidemic risk. To improve the verification of diagnosis in the practice of a phthisiologist, molecular genetic methods for the search for mycobacteria are increasingly used, based on the identification of specific fragments of the DNA chain in the diagnostic material. The most widely used method is the polymerase chain reaction (PCR), which is based on directed DNA amplification. The latest innovation is fully automated systems using cartridge technology GeneXpert. The advantages of GeneXpert are high sensitivity, speed (result in 2 hours), real-time PCR detection, exclusion of sample contamination. The technique of cartridge technology is constantly being improved, various cartridges are used on its platform, which not only detect M. tuberculosis, but also determine the sensitivity to anti-tuberculosis drugs - rifampicin (MTB / RIF cartridge) or several anti-TB drugs (MTB / XDR). Cartridges have been developed that are able to detect Mycobacterium tuberculosis (MBT) at an even lower concentration in the test material - MTB / RIF (Ultra). GeneXpert technology can be used to diagnose extrapulmonary tuberculosis by examining various biological materials, which are more effective in detecting tuberculosis in children and adolescents, in HIV-positive individuals.

Health extension workers contribution on tuberculosis case notification in Tigray region, Northern Ethiopia: A concurrent mixed method study

Background

Despite the emphasis placed on Community Based Tuberculosis Care (CBTC) implementation by Health Extension Workers (HEWs) within the National Tuberculosis Program (NTP) in Ethiopia, there is little evidence on contribution of HEWs on TB case notification. Therefore, this study aimed to describe the contribution of HEWs on TB case notification and its associated factors in Tigray region, Northern Ethiopia.

Methods

A concurrent mixed method (quantitative and qualitative) cross-sectional study design was conducted in three randomly selected districts in Tigray region, Northern Ethiopia. Quantitative data were collected using a pre-tested semi-structured questionnaire. Qualitative data were collected using Focused Group Discussions (FGDs) and Key Informant Interviews (KIIs) to further describe the community participation and presumptive TB identification and referral system. For the quantitative data, binary logistic regression analysis was done and all variables with P-value of < 0.25 in bivariate analysis were included in the multi-variable model to see predictors of HEWs contribution to TB notification. The qualitative data were thematically analyzed using Atlas.ti version 7.

Results

In this study, a total of 68 HEWs were included. From March 1, 2017 to February 28, 2018, a total of 427 TB cases notified in the study areas and one-third (34%) of them were notified by the HEWs referral. Provision of Community Based-Directly Observed Treatment Short course (CB–DOTS) (Adjusted Odds Ratio (AOR) = 3.63, 95% Confidence Interval (CI) = 1.18–11.19) and involvement of community volunteers on CBTC (AOR = 3.31, 95% CI = 1.10–10.09) were significantly associated with the contribution of HEWs on TB case notification. The qualitative findings indicated that high workload of HEWs, inaccessibility of TB diagnostic services at nearby health facilities, and transportation and investigation costs were identified as factors affecting for presumptive TB referral by HEWs.

Conclusions

Provision of CB-DOTS and involvement of community volunteers in CBTC activities should be strengthened to improve the HEWs contribution on TB case notification. Additionally, HEWs should be empowered and further interventions of TB diagnostic services at diagnostic health facilities are needed to improve presumptive TB referral by HEWs.

Population-based sequencing of Mycobacterium tuberculosis reveals how current population dynamics are shaped by past epidemics

Transmission is a driver of tuberculosis (TB) epidemics in high-burden regions, with assumed negligible impact in low-burden areas. However, we still lack a full characterization of transmission dynamics in settings with similar and different burdens. Genomic epidemiology can greatly help to quantify transmission, but the lack of whole genome sequencing population-based studies has hampered its application. Here, we generate a population-based dataset from Valencia region and compare it with available datasets from different TB-burden settings to reveal transmission dynamics heterogeneity and its public health implications. We sequenced the whole genome of 785 Mycobacterium tuberculosis strains and linked genomes to patient epidemiological data. We use a pairwise distance clustering approach and phylodynamic methods to characterize transmission events over the last 150 years, in different TB-burden regions. Our results underscore significant differences in transmission between low-burden TB settings, i.e., clustering in Valencia region is higher (47.4%) than in Oxfordshire (27%), and similar to a high-burden area as Malawi (49.8%). By modeling times of the transmission links, we observed that settings with high transmission rate are associated with decades of uninterrupted transmission, irrespective of burden. Together, our results reveal that burden and transmission are not necessarily linked due to the role of past epidemics in the ongoing TB incidence, and highlight the need for in-depth characterization of transmission dynamics and specifically tailored TB control strategies.

Alert sign and symptoms for the early diagnosis of pulmonary tuberculosis: analysis of patients followed by a tertiary pediatric hospital

Background

Intercepting earlier suspected TB (Tuberculosis) cases clinically is necessary to reduce TB incidence, so we described signs and symptoms of retrospective cases of pulmonary TB and tried to evaluate which could be early warning signs.

Methods

We conducted a retrospective descriptive study of pulmonary TB cases in children in years 2005–2017; in years 2018–2020 we conducted a cohort prospective study enrolling patients < 18 years accessed to Emergency Department (ED) with signs/symptoms suggestive of pulmonary TB.

Results

In the retrospective analysis, 226 patients with pulmonary TB were studied. The most frequently described items were contact history (53.5%) and having parents from countries at risk (60.2%). Cough was referred in 49.5% of patients at onset, fever in 46%; these symptoms were persistent (lasting ≥ 10 days) in about 20%. Lymphadenopathy is described in 15.9%. The prospective study enrolled 85 patients of whom 14 (16.5%) were confirmed to be TB patients and 71 (83.5%) were non-TB cases. Lymphadenopathy and contact history were the most correlated variables. Fever and cough lasting ≥ 10 days were less frequently described in TB cases compared to non-TB patients (p < 0.05).

Conclusions

In low TB endemic countries, pulmonary TB at onset is characterized by different symptoms, i.e. persistent fever and cough are less described, while more relevant are contact history and lymphadenopathy. It was not possible to create a score because signs/symptoms usually suggestive of pulmonary TB (considered in the questionnaire) were not significant risk factors in our reality, a low TB country.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13052-022-01288-5.

Effectiveness of nationwide programmatic testing and treatment for latent tuberculosis infection in migrants in England: a retrospective, population-based cohort study

Background

In low-incidence countries, tuberculosis mainly affects migrants, mostly resulting from reactivation of latent tuberculosis infection (LTBI) acquired in high-incidence countries before migration. A nationwide primary care-based LTBI testing and treatment programme for migrants from high-incidence countries was therefore established in high tuberculosis incidence areas in England. We aimed to assess the effectiveness of this programme.

Methods

We did a retrospective, population-based cohort study of migrants who registered in primary care between Jan 1, 2011, and Dec 31, 2018, in 55 high-burden areas with programmatic LTBI testing and treatment. Eligible individuals were aged 16–35 years, born in a high-incidence country, and had entered England in the past 5 years. Individuals who tested interferon-γ release assay (IGRA)-negative were advised about symptoms of tuberculosis, whereas those who tested IGRA-positive were clinically assessed to rule out active tuberculosis and offered preventive therapy. The primary outcome was incident tuberculosis notified to the national Enhanced Tuberculosis Surveillance system.

Findings

Our cohort comprised 368 097 eligible individuals who had registered in primary care, of whom 37 268 (10·1%) were tested by the programme. 1446 incident cases of tuberculosis were identified: 166 cases in individuals who had IGRA testing (incidence 204 cases [95% CI 176–238] per 100 000 person-years) and 1280 in individuals without IGRA testing (82 cases [77–86] per 100 000 person-years). Overall, in our primary analysis including all diagnosed tuberculosis cases, a time-varying association was identified between LTBI testing and treatment and lower risk of incident tuberculosis (hazard ratio [HR] 0·76 [95% CI 0·63–0·91]) when compared with no testing. In stratified analysis by follow-up period, the intervention was associated with higher risk of tuberculosis diagnosis during the first 6 months of follow-up (9·93 [7·63–12·9) and a lower risk after 6 months (0·57 [0·41–0·79]). IGRA-positive individuals had higher risk of tuberculosis diagnosis than IGRA-negative individuals (31·9 [20·4–49·8]). Of 37 268 migrants who were tested, 6640 (17·8%) were IGRA-positive, of whom 1740 (26·2%) started preventive treatment. LTBI treatment lowered the risk of tuberculosis: of 135 incident cases in the IGRA-positive cohort, seven cases were diagnosed in the treated group (1·87 cases [95% CI 0·89–3·93] per 1000 person-years) and 128 cases were diagnosed in the untreated group (10·9 cases [9·16–12·9] per 1000 person-years; HR 0·14 [95% CI 0·06–0·32]).

Interpretation

A low proportion of eligible migrants were tested by the programme and a small proportion of those testing positive started treatment. Despite this, programmatic LTBI testing and treatment of individuals migrating to a low-incidence region is effective at diagnosing active tuberculosis earlier and lowers the long-term risk of progression to tuberculosis. Increasing programme participation and treatment rates for those testing positive could substantially impact national tuberculosis incidence.

Funding

National Institute for Health Research Health Protection Research Unit in Respiratory Infections.

XDR-TB Transmitted from Mother to 10-Month-Old Infant: Diagnostic and Therapeutic Problems

Drug-resistant TB (DR-TB) in children is a special epidemiological, clinical, and diagnostic problem, and its global incidence remains unknown. DR-TB in children is usually of a primary nature and is most often transmitted to the child from a household contact, so these cases reflect the prevalence of DR-TB in the population of adult patients. The risk of infection with Mycobacterium tuberculosis complex (MTBC) in children depends on age, duration of exposure, proximity of contact with the infected person, and the level of source virulence. Most cases of TB in children, especially in infants, are caused by household contacts, where the main sources of infection are parents, grandparents or older siblings. However, there are many documented cases of TB transmission outside the family. The most common source of infection is an adult who is profusely positive for mycobacteria, diagnosed too late, and inadequately treated. It has been estimated that a sputum-positive patient might infect 30–50% of their household members. For this reason, active epidemiological investigation and contact tracing in the environment of sputum-positive patients are the most appropriate methods of identifying infected family members. This paper presents a case report concerning the transmission of extensively drug-resistant TB, Beijing 265 genotype, from a mother to her 10-month-old daughter. It is the first case diagnosed in Poland, and one of very few described in the literature where treatment was effective in the mother and the infant recovered spontaneously.

Pooled testing of sputum with Xpert MTB/RIF and Xpert Ultra during tuberculosis active case finding campaigns in Lao People's Democratic Republic

INTRODUCTION

Active case finding (ACF) of individuals with tuberculosis (TB) is a key intervention to find the 30% of people missed every year. However, ACF requires screening large numbers of individuals who have a low probability of positive results, typically <5%, which makes using the recommended molecular tests expensive.

METHODS

We conducted two ACF surveys (in 2020 and 2021) in high TB burden areas of Lao PDR. Participants were screened for TB symptoms and received a chest X-ray. Sputum samples of four consecutive individuals were pooled and tested with Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) (Xpert-MTB/RIF) (2020) or Xpert-Ultra (2021). The agreement of the individual and pooled samples was compared and the reasons for discrepant results and potential cartridge savings were assessed.

RESULTS

Each survey included 436 participants, which were tested in 109 pools. In the Xpert-MTB/RIF survey, 25 (sensitivity 89%, 95% CI 72.8% to 96.3%) of 28 pools containing MTB-positive samples tested positive and 81 pools containing only MTB-negative samples tested negative (specificity 100%, 95% CI 95.5% to 100%). In the Xpert-Ultra survey, all 32 (sensitivity 100%, 95% CI 89.3% to 100%) pools containing MTB-positive samples tested positive and all 77 (specificity 100%, 95% CI 95.3% to 100%) containing only MTB-negative samples tested negative. Pooling with Xpert-MTB/RIF and Xpert-Ultra saved 52% and 46% (227/436 and 199/436, respectively) of cartridge costs alone.

CONCLUSION

Testing single and pooled specimens had a high level of agreement, with complete concordance when using Xpert-Ultra. Pooling samples could generate significant cartridge savings during ACF campaigns.

Household contact investigation for the detection of active tuberculosis and latent tuberculosis: a comprehensive evaluation in two high-burden provinces in Iran

Background

Systematic evaluation of household contacts of persons with pulmonary tuberculosis (TB) in low- and middle-income countries is recommended by the World Health Organization (WHO). This study recruited adult household contacts of diagnosed TB patients in two high burden provinces of Iran to estimate the prevalence and incidence of active disease and latent TB infection (LTBI) among individuals exposed to TB cases.

Methods

We conducted a cohort study among adults in household contact with a pulmonary TB index case. All subjects were assessed for active disease through evaluation of symptoms. Tuberculin skin test (TST) and QuantiFERON®-TB Gold Plus (QFT-Plus) were used to define LTBI. These tests were performed at the time of the index TB case diagnosis and repeated if the previous result was negative, at three-, 12-, and 18-months post recruitment. In addition, interferon-γ-induced protein-10 (IP-10) concentrations were measured in QFT-Plus supernatants for all participants three months after diagnosing the index case.

Results

A total of 451 individuals who had close contact with 95 active TB patients were enrolled in this study. Five (1.1%) contacts were diagnosed with active TB and 285 (63.2%) were identified with LTBI during our study. The incidence rate of LTBI among adult household contacts of TB index cases was 0.44 per person per year.

Conclusion

The overall rate of LTBI was high. Systematic screening of all household contacts of pulmonary TB should be expanded in Iran to make the timely achievement of the global end TB strategy feasible.

Impact of early chest radiography on delay in pulmonary tuberculosis case notification in Ethiopia

Background:

One-third of tuberculosis (TB) cases are missed each year and delays in the diagnosis of TB are hampering the whole cascade of care. Early chest X-ray (CXR) in patients with cough irrespective of duration may reduce TB diagnostic and treatment delays and increase the number of TB patients put into TB care. We aimed to evaluate the impact of CXR on delay in the diagnosis of pulmonary tuberculosis (PTB) among people with cough of any duration.

Methods:

A facility-based cross-sectional study was conducted in four selected health facilities from two regions and two city administrations of Ethiopia. Patients who sought health care were screened for cough of any duration, and those with cough underwent CXR for PTB and their sputum specimens were tested for microbiological confirmation. Delays were followed up and calculated using median and inter-quartile range (IQR) to summarize (first onset of cough to first facility visit, ≥15 days), diagnosis delay (first facility visit to date of PTB diagnosis, >7 days), and total delay (first onset of cough to date of PTB diagnosis, >21 days). Kruskal–Wallis and Mann–Witney tests were used to compare the delays among independent variables.

Results:

A total of 309 PTB cases were consecutively diagnosed of 1853 presumptive TB cases recruited in the study that were identified from 2647 people who reported cough of any duration. The median (IQR) of patient delay, diagnosis delay, and the total delay was 30 (16–44), 1 (0–3), and 31 (19–48) days, respectively. Patients’ delay contributed a great role in the total delay, 201/209 (96.2%). Median diagnosis delay was higher among those that visited health center, diagnosed at a facility that had no Xpert mycobacterium tuberculosis (MTB)/RIF assay, radiologist, or CXR (P < 0.05). Factors associated with patients delay were history of previous TB treatment (adjusted prevalence ratio [aPR] = 0.79, 95% confidence interval [CI]: 0.63–0.99) and history of weight loss (aPR = 1.12; 95% CI: 1.0–1.25). Early CXR screening for cough of <2 weeks duration significantly reduced the patients’ delay and thus the total delay, but not diagnostic delay alone.

Conclusion:

Early screening using CXR minimized delays in the diagnosis of PTB among people with cough of any duration. Patients’ delay was largest and contributed great role in the delay of TB cases. Screening by cough of any duration and/or CXR among people seeking healthcare along with ensuring the availability of Xpert MTB/RIF assay and skilled human power at primary healthcare facilities are important to reduce patient and diagnostic delays of PTB in Ethiopia.

Economic Evaluation of Community Tuberculosis Active Case-Finding Approaches in Cambodia: A Quasi-Experimental Study

This study aimed to estimate the costs and incremental cost-effectiveness of two community-based tuberculosis (TB) active case-finding (ACF) strategies in Cambodia. We also assessed the number needed to screen and test to find one TB case. Program and national TB notification data from a quasi-experimental study of a cohort of people with TB in 12 intervention operational districts (ODs) and 12 control ODs between November 2018 and December 2019 were analyzed. Two ACF interventions (ACF seed-and-recruit (ACF SAR) model and one-off roving (one-off) ACF) were implemented concurrently. The matched control sites included PCF only. We estimated costs using the program and published data in Cambodia. The primary outcome was disability-adjusted life years (DALY) averted over 14 months. We considered the gross domestic product per capita of Cambodia in 2018 as the cost-effectiveness threshold. ACF SAR needed to test 7.7 people with presumptive TB to identify one all-forms TB, while one-off ACF needed to test 22.4. The costs to diagnose one all-forms TB were USD 458 (ACF SAR) and USD 191 (one-off ACF). The incremental cost per DALY averted was USD 257 for ACF SAR and USD 204 for one-off ACF. Community-based ACF interventions that targeted key populations for TB in Cambodia were highly cost-effective.

Active Case Finding for Tuberculosis in India: A Syntheses of Activities and Outcomes Reported by the National Tuberculosis Elimination Programme

India launched a national community-based active TB case finding (ACF) campaign in 2017 as part of the strategic plan of the National Tuberculosis Elimination Programme (NTEP). This review evaluated the outcomes for the components of the ACF campaign against the NTEP’s minimum indicators and elicited the challenges faced in implementation. We supplemented data from completed pretested data proformas returned by ACF programme managers from nine states and two union territories (for 2017–2019) and five implementing partner agencies (2013–2020), with summary national data on the state-wise ACF outcomes for 2018–2020 published in annual reports by the NTEP. The data revealed variations in the strategies used to map and screen vulnerable populations and the diagnostic algorithms used across the states and union territories. National data were unavailable to assess whether the NTEP indicators for the minimum proportions identified with presumptive TB among those screened (5%), those with presumptive TB undergoing diagnostic tests (>95%), the minimum sputum smear positivity rate (2% to 3%), those with negative sputum smears tested with chest X-rays or CBNAAT (>95%) and those diagnosed through ACF initiated on anti-TB treatment (>95%) were fulfilled. Only 30% (10/33) of the states in 2018, 23% (7/31) in 2019 and 21% (7/34) in 2020 met the NTEP expectation that 5% of those tested through ACF would be diagnosed with TB (all forms). The number needed to screen to diagnose one person with TB (NNS) was not included among the NTEP’s programme indicators. This rough indicator of the efficiency of ACF varied considerably across the states and union territories. The median NNS in 2018 was 2080 (interquartile range or IQR 517–4068). In 2019, the NNS was 2468 (IQR 1050–7924), and in 2020, the NNS was 906 (IQR 108–6550). The data consistently revealed that the states that tested a greater proportion of those screened during ACF and used chest X-rays or CBNAAT (or both) to diagnose TB had a higher diagnostic yield with a lower NNS. Many implementation challenges, related to health systems, healthcare provision and difficulties experienced by patients, were elicited. We suggest a series of strategic interventions addressing the implementation challenges and the six gaps identified in ACF outcomes and the expected indicators that could potentially improve the efficacy and effectiveness of community-based ACF in India.

The impact of active case finding on transmission dynamics of tuberculosis: A modelling study

Background

In the last decade, active case finding (ACF) strategies for tuberculosis (TB) have been implemented in many diverse settings, with some showing large increases in case detection and reporting at the sub-national level. There have also been several studies which seek to provide evidence for the benefits of ACF to individuals and communities in the broader context. However, there remains no quantification of the impact of ACF with regards to reducing the burden of transmission. We sought to address this knowledge gap and quantify the potential impact of active case finding on reducing transmission of TB at the national scale and further, to determine the intensification of intervention efforts required to bring the reproduction number (R₀) below 1 for TB.

Methods

We adopt a dynamic transmission model that incorporates heterogeneity in risk to TB to assess the impact of an ACF programme (IMPACT TB) on reducing TB incidence in Vietnam and Nepal. We fit the models to country-level incidence data using a Bayesian Markov Chain Monte Carlo approach. We assess the impact of ACF using a parameter in our model, which we term the treatment success rate. Using programmatic data, we estimate how much this parameter has increased as a result of IMPACT TB in the implementation districts of Vietnam and Nepal and quantify additional efforts needed to eliminate transmission of TB in these countries by 2035.

Results

Extending the IMPACT TB programme to national coverage would lead to moderate decreases in TB incidence and would not be enough to interrupt transmission by 2035. Decreasing transmission sufficiently to bring the reproduction number (R0) below 1, would require a further intensification of current efforts, even at the sub-national level.

Conclusions

Active case finding programmes are effective in reducing TB in the short term. However, interruption of transmission in high-burden countries, like Vietnam and Nepal, will require comprehensive incremental efforts. Complementary measures to reduce progression from infection to disease, and reactivation of latent infection, are needed to meet the WHO End TB incidence targets.

Pattern of abnormalities amongst chest X-rays of adults undergoing computer-assisted digital chest X-ray screening for tuberculosis in Peri-Urban Blantyre, Malawi: A cross-sectional study

BACKGROUND

The prevalence of diseases other than tuberculosis (TB) detected during chest X-ray screening is poorly described in sub-Saharan Africa. Computer-assisted digital chest X-ray technology is available for TB screening and has the potential to be a screening tool for non-communicable diseases as well. Low- and middle-income countries are in a transition period where the burden of non-communicable diseases is increasing, but health systems are mainly focused on addressing infectious diseases.

METHODS

Participants were adults undergoing computer-assisted chest X-ray screening for tuberculosis in a community-wide tuberculosis prevalence survey in Blantyre, Malawi. Adults with abnormal radiographs by field radiographer interpretation were evaluated by a physician in a community-based clinic. X-ray classifications were compared to classifications of a random sample of normal chest X-rays by radiographer interpretation. Radiographic features were classified using WHO Integrated Management for Adult Illnesses (IMAI) guidelines. All radiographs taken at the screening tent were analysed by the Qure.ai qXR v2.0 software.

RESULTS

5% (648/13,490) of adults who underwent chest radiography were identified to have an abnormal chest X-ray by the radiographer. 387 (59.7%) of the participants attended the X-ray clinic, and another 387 randomly sampled normal X-rays were available for comparison. Participants who were referred to the community clinic had a significantly higher HIV prevalence than those who had been identified to have a normal CXR by the field radiographer (90 [23.3%] vs. 43 [11.1%] p-value < 0.001). The commonest radiographic finding was cardiomegaly (20.7%, 95% CI 18.0-23.7). One in five (81/387) chest X-rays were misclassified by the radiographer. The overall mean Qure.ai qXR v2.0 score for all reviewed X-rays was 0.23 (SD 0.20). There was a high concordance of cardiomegaly classification between the physician and the computer-assisted software (109/118, 92.4%).

CONCLUSION

There is a high burden of cardiomegaly on a chest X-ray at a community level, much of which is in patients with diabetes, heart disease and high blood pressure. Cardiomegaly on chest X-ray may be a potential tool for screening for cardiovascular NCDs at the primary care level as well as in the community.

Adherence of HIV clinics to guidelines for the delivery of TB screening among people living with HIV/AIDS in Ghana

Background

Tuberculosis screening of people living with HIV (PLHIV) – an intervention to reduce the burden of TB among PLHIV – is being implemented at HIV clinics in Ghana since 2007, but TB screening coverage remains low. Facility adherence to intervention guidelines may be a factor but is missing in implementation science literature. This study assesses the level of HIV clinic adherence to the guidelines and related facility characteristics in selected district hospitals in Ghana.

Methods

This cross-sectional study was conducted in all 27 district hospitals with HIV clinics, X-ray and geneXpert machines in Ghana. These hospitals are in 27 districts representing about 27% of the 100 district hospitals with HIV clinics in Ghana. A data collection tool with 18-items (maximum score of 29) was developed from the TB/HIV collaborative guidelines to assess facility adherence to four interrelated components of the TB screening programme as stated in the guidelines: intensive TB case-finding among PLHIV (ITCF), Isoniazid preventive therapy initiation (IPT), TB infection control (TIC), and programme review meetings (PRM). Data were collected through record review and interviews with 27 key informants from each hospital. Adherence scores per component were summed to determine an overall adherence score per facility and summarized using medians and converted to proportions. Facility characteristics were assessed and compared across facilities with high (above median) versus low (below median) overall adherence scores, using nonparametric test statistics.

Results

From the 27 key interviews and facility records reviewed, the median adherence scores for ITCF, IPT, TIC, and PRM components were 85.7% (IQR: 85.5–100.0), 0% (IQR: 0–66.7), 33.3% (IQR: 33.3–50.0), and 90.0% (IQR: 70.0–90.0), respectively. The overall median adherence score was 62.1% (IQR: 58.6–65.1), and 17 clinics (63%) with overall adherence score above the median were categorized as high adherence. Compared to low adherence facilities, high adherence facilities had statistically significant lower PLHIV clinic attendees per month (256 (IQR: 60–904) vs. 900 (IQR: 609–2622); p = 0.042), and lower HIV provider workloads (28.6 (IQR: 8.6–113) vs. 90 (IQR: 66.7–263.5); p = 0.046), and most had screening guidelines (76%, p < 0.01) and questionnaire (80%, p < 0.01) available on-site.

Conclusion

PRM had highest score while the IPT component had the lowest score. Almost a third of the facilities implemented the TB screening programme activities with a high level of adherence to the guidelines. We suggest to ensure adherence to all four components, reducing staff workloads and making TB screening questionnaires and guidelines available on-site would increase facility adherence to the intervention and ultimately achieve intervention targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07121-9.

Does tuberculosis screening improve individual outcomes? A systematic review

BACKGROUND

To determine if tuberculosis (TB) screening improves patient outcomes, we conducted two systematic reviews to investigate the effect of TB screening on diagnosis, treatment outcomes, deaths (clinical review assessing 23 outcome indicators); and patient costs (economic review).

METHODS

Pubmed, EMBASE, Scopus and the Cochrane Library were searched between 1/1/1980-13/4/2020 (clinical review) and 1/1/2010-14/8/2020 (economic review). As studies were heterogeneous, data synthesis was narrative.

FINDINGS

Clinical review: of 27,270 articles, 18 (n=3 trials) were eligible. Nine involved general populations. Compared to passive case finding (PCF), studies showed lower smear grade (n=2/3) and time to diagnosis (n=2/3); higher pre-treatment losses to follow-up (screened 23% and 29% vs PCF 15% and 14%; n=2/2); and similar treatment success (range 68-81%; n=4) and case fatality (range 3-11%; n=5) in the screened group. Nine reported on risk groups. Compared to PCF, studies showed lower smear positivity among those culture-confirmed (n=3/4) and time to diagnosis (n=2/2); and similar (range 80-90%; n=2/2) treatment success in the screened group. Case fatality was lower in n=2/3 observational studies; both reported on established screening programmes. A neonatal trial and post-hoc analysis of a household contacts trial found screening was associated with lower all-cause mortality. Economic review: From 2841 articles, six observational studies were eligible. Total costs (n=6) and catastrophic cost prevalence (n=4; range screened 9-45% vs PCF 12-61%) was lower among those screened.

INTERPRETATION

We found very limited patient outcome data. Collecting and reporting this data must be prioritised to inform policy and practice.

FUNDING

WHO and EDCTP.

Comparison of yield and relative costs of different screening algorithms for tuberculosis in active case-finding: a cross-section study

Background

Part of tuberculosis (TB) patients were missed if symptomatic screening was based on the main TB likely symptoms. This study conducted to compare the yield and relative costs of different TB screening algorithms in active case-finding in the whole population in China.

Methods

The study population was screened based on the TB likely symptoms through a face-to-face interview in selected 27 communities from 10 counties of 10 provinces in China. If the individuals had any of the enhanced TB likely symptoms, both chest X-ray and sputum tests were carried out for them furtherly. We used the McNemar test to analyze the difference in TB detection among four algorithms in active case-finding. Of four algorithms, two were from WHO recommendations including 1a/1c, one from China National Tuberculosis Program, and one from this study with the enhanced TB likely symptoms. Furthermore, a two-way ANOVA analysis was performed to analyze the cost difference in the performance of active case-finding adjusted by different demographic and health characteristics among different algorithms.

Results

Algorithm with the enhanced TB likely symptoms defined in this study could increase the yield of TB detection in active case-finding, compared with algorithms recommended by WHO (p < 0.01, Kappa 95% CI: 0. 93–0.99) and China NTP (p = 0.03, Kappa 95% CI: 0.96–1.00). There was a significant difference in the total costs among different three algorithms WHO 1c/2/3 (F = 59.13, p < 0.01). No significant difference in the average costs for one active TB case screened and diagnosed through the process among Algorithms 1c/2/3 was evident (F = 2.78, p = 0.07). The average costs for one bacteriological positive case through algorithm WHO 1a was about two times as much as the costs for one active TB case through algorithms WHO 1c/2/3.

Conclusions

Active case-finding based on the enhanced symptom screening is meaningful for TB case-finding and it could identify more active TB cases in time. The findings indicated that this enhanced screening approach cost more compared to algorithms recommend by WHO and China NTP, but the increased yield resulted in comparative costs per patient. And it cost much more that only smear/bacteriological-positive TB cases are screened in active case-finding.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06486-w.

Effectiveness of spatially targeted interventions for control of HIV, tuberculosis, leprosy and malaria: a systematic review

BACKGROUND

As infectious diseases approach global elimination targets, spatial targeting is increasingly important to identify community hotspots of transmission and effectively target interventions. We aimed to synthesise relevant evidence to define best practice approaches and identify policy and research gaps.

OBJECTIVE

To systematically appraise evidence for the effectiveness of spatially targeted community public health interventions for HIV, tuberculosis (TB), leprosy and malaria.

DESIGN

Systematic review.

DATA SOURCES

We searched Medline, Embase, Global Health, Web of Science and Cochrane Database of Systematic Reviews between 1 January 1993 and 22 March 2021.

STUDY SELECTION

The studies had to include HIV or TB or leprosy or malaria and spatial hotspot definition, and community interventions.

DATA EXTRACTION AND SYNTHESIS

A data extraction tool was used. For each study, we summarised approaches to identifying hotpots, intervention design and effectiveness of the intervention.

RESULTS

Ten studies, including one cluster randomised trial and nine with alternative designs (before-after, comparator area), satisfied our inclusion criteria. Spatially targeted interventions for HIV (one USA study), TB (three USA) and leprosy (two Brazil, one Federated States of Micronesia) each used household location and disease density to define hotspots followed by community-based screening. Malaria studies (one each from India, Indonesia and Kenya) used household location and disease density for hotspot identification followed by complex interventions typically combining community screening, larviciding of stagnant water bodies, indoor residual spraying and mass drug administration. Evidence of effect was mixed.

CONCLUSIONS

Studies investigating spatially targeted interventions were few in number, and mostly underpowered or otherwise limited methodologically, affecting interpretation of intervention impact. Applying advanced epidemiological methodologies supporting more robust hotspot identification and larger or more intensive interventions would strengthen the evidence-base for this increasingly important approach.

PROSPERO REGISTRATION NUMBER

CRD42019130133.

Challenges in delivery of tuberculosis Services in Ethiopian Pastoralist Settings: clues for reforming service models and organizational structures

Background

The End-TB strategy aims to see a world free of tuberculosis (TB) by the coming decade through detecting and treating all cases irrespective of socioeconomic inequalities. However, case detections and treatment outcomes have not been as they should be in Somali pastoral settings of Ethiopia. Hence, this study aimed to explore the challenges that hinder the delivery and utilization of TB services in pastoral areas.

Methods

A qualitative study was conducted between December 2017 and October 2018 among pastoralist patients with delay of ≥2 months in seeking healthcare, healthcare providers and programme managers. Data were collected from different sources using 41 in-depth interviews, observations of facilities and a review meeting of providers from 50 health facilities. The data were transcribed, coded and analyzed to identify pre-defined and emerging sub-themes. ATLAS.ti version 7.0 was used for coding data, categorizing codes, and visualizing networks.

Results

Poor knowledge of TB and its services, limited accessibility (unreachability, unavailability and unacceptability), pastoralism, and initial healthcare-seeking at informal drug vendors that provide improper medications were the key barriers hindering the uptake of TB medical services. Inadequate infrastructure, shortage of trained and enthused providers, interruptions of drugs and laboratory supplies, scarce equipment, programme management gaps, lack of tailored approach, low private engagement, and cross-border movement were the major challenges affecting the provision of TB services for pastoral communities. The root factors were limited potential healthcare coverage, lack of zonal and district TB units, mobility and drought, strategy and funding gaps, and poor development infrastructure.

Conclusion

In pastoral settings of Ethiopia, the major challenges of TB services are limited access, illicit medication practices, inadequate resources, structural deficits, and lack of tailored approaches. Hence, for the pastoral TB control to be successful, mobile screening and treatment modalities and engaging rural drug vendors will be instrumental in enhancing case findings and treatment compliance; whereas, service expansion and management decentralization will be essential to create responsive structures for overcoming challenges.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06662-3.

The effectiveness of contact investigation among contacts of tuberculosis patients: a systematic review and meta-analysis

BACKGROUND

We aimed to evaluate the effectiveness of contact investigation in comparison to passive case-detection alone and estimated the yield of co-prevalent and incident tuberculosis (TB), and latent tuberculosis infection (LTBI) among contacts of patients with TB.

METHODS

A systematic search was undertaken of studies published between January 1, 2011 and October 1, 2019 in the English language. The proportion of contacts diagnosed with co-prevalent TB, incident TB and/or LTBI was estimated. Evaluation of the effectiveness of contact investigation included randomised trials, while the yield of contact investigation (co-prevalent and incident TB and LTBI) was assessed in non-randomised studies.

RESULTS

Data were extracted from 244 studies, of which 187 studies measured the proportion of contacts diagnosed with TB disease and 135 studies measured LTBI prevalence. Individual randomised trials demonstrated that contact investigation increased TB case notification (RR 2.5 [95% CI: 2.0-3.2]), TB case detection (OR 1.34 [95% CI: 0.43-4.24]) and decreased mortality (RR 0.6 [95% CI: 0.4-0.8]) and population TB prevalence (risk ratio 0.82 [95% CI: 0.64-1.04]).The overall pooled prevalence of TB was 3.6% (95% CI: 3.3-4.0%; I²=98.9%, 181 studies). The pooled prevalence of microbiologically-confirmed TB was 3.2% (95% CI: 2.6-3.7%; I²=99.5%, 106 studies). The pooled incidence of TB was highest in the first year after exposure to index patients (2.0%, 95% CI: 1.1-3.3%; I²=96.2%, 14 studies) and substantially lower five years after exposure to index patient (0.5%, 95% CI: 0.3-0.9%; 1 study). The pooled prevalence of LTBI among contacts was 42.4% (95% CI: 38.5-46.4%; I²=99.8%, 135 studies).

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis found that contact investigation was effective in high-burden settings. The higher pooled prevalence estimates of microbiologically-confirmed TB compared to previous reviews suggests newer rapid molecular diagnostics contribute to increased case detection.

Increasing smear positive tuberculosis detection using a clinical score - A stepped wedge multicenter trial from Africa

BACKGROUND

The Bandim TBscore is a clinical score that predicts treatment outcome in Tuberculosis (TB) patients and proved useful as an indicator of which healthcare-seeking adults to refer for sputum smear microcopy. We aimed to test in a randomized trial if the TBscore could be used to enhance the detection of smear positive (SP) TB.

METHODS

We carried out a stepped wedge cluster-randomized trial at six health centers in Bissau, Guinea-Bissau, and Gondar, Ethiopia. The primary outcome was diagnostic yield for SP TB. Secondary outcomes were successful treatment and effect on overall 12 months mortality. The study was registered at the Pan African Clinical Trials Registry (PACTR201611001838365).

RESULTS

We included 3571 adults. Overall, there was no effect of the intervention on SP PTB detected (OR 1.39 (95%CI 0.75 - 2.56). Analysis stratified by country, showed that the TBscore increased case detection in Gondar (OR 4.05 (95%CI 1.67 - 9.85)) but no effect was found in Bissau (OR 0.47 (95%CI 0.22 - 1.05)) where take-up was much lower. Overall mortality decreased during the intervention (HR 0.31 (95%CI 0.13-0.72)).

CONCLUSION

Using the TBscore for triage before smear microscopy may improve case detection and decrease mortality if there is sufficient laboratory capacity to increase sputum smears.

'A double-edged sword': Perceived benefits and harms of active case-finding for people with presumptive tuberculosis and communities-A qualitative study based on expert interviews

BACKGROUND

Active case-finding (ACF), also referred to as community-based tuberculosis screening, is a component of the World Health Organization's End TB Strategy. ACF has potential benefits but also harms, which need to be carefully assessed when developing and implementing ACF policies. While empirical evidence on the benefits of ACF is still weak, evidence on the harms is even weaker. This study aimed to explore experts' views on the benefits and harms of ACF for people with presumptive TB and communities.

METHODS

This was an exploratory study. Semi-structured interviews were conducted with a purposive sample of 39 experts from international, non-governmental/non-profit organizations, funders, government institutions, international societies, think tanks, universities and research institutions worldwide. Framework analysis was applied.

RESULTS

Findings elaborated perceived benefits of ACF, including reaching vulnerable populations, reducing patient costs, helping raise awareness for tuberculosis among individuals and engaging communities, and reducing tuberculosis transmission. Perceived harms included increasing stigma and discrimination, causing false-positive diagnoses, as well as triggering other unintended consequences related to screening for tuberculosis patients, such as deportation of migrants once confirmed to have tuberculosis. Most of the perceived benefits of ACF could be linked to its objective of finding and treating persons with tuberculosis early (theme 1), while ACF was also perceived as a "double-edged sword" and could cause harms, if inappropriately designed and implemented (theme 2). The analysis underlined the importance of considering the benefits and harms of ACF throughout the screening pathway. The study provides new insights into the perceived benefits and harms of ACF from the perspectives of experts in the field.

CONCLUSION

This study highlights gaps in the evidence base surrounding ACF and can stimulate further research, debate and analysis regarding the benefits and harms of ACF to inform contextual optimization of design and implementation of ACF strategies.

Protective impacts of household-based tuberculosis contact tracing are robust across endemic incidence levels and community contact patterns

There is an emerging consensus that achieving global tuberculosis control targets will require more proactive case finding approaches than are currently used in high-incidence settings. Household contact tracing (HHCT), for which households of newly diagnosed cases are actively screened for additional infected individuals is a potentially efficient approach to finding new cases of tuberculosis, however randomized trials assessing the population-level effects of such interventions in settings with sustained community transmission have shown mixed results. One potential explanation for this is that household transmission is responsible for a variable proportion of population-level tuberculosis burden between settings. For example, transmission is more likely to occur in households in settings with a lower tuberculosis burden and where individuals mix preferentially in local areas, compared with settings with higher disease burden and more dispersed mixing. To better understand the relationship between endemic incidence levels, social mixing, and the impact of HHCT, we developed a spatially explicit model of coupled household and community transmission. We found that the impact of HHCT was robust across settings of varied incidence and community contact patterns. In contrast, we found that the effects of community contact tracing interventions were sensitive to community contact patterns. Our results suggest that the protective benefits of HHCT are robust and the benefits of this intervention are likely to be maintained across epidemiological settings.

Extending contact screening within a 50-m radius of an index tuberculosis patient using Xpert MTB/RIF in urban Pakistan: Did it impact treatment outcomes?

BACKGROUND

Pakistan implemented initiatives to detect tuberculosis (TB) patients through extended contact screening (ECS); it improved case detection but treatment outcomes need assessment.

OBJECTIVES

To compare treatment outcomes of pulmonary TB (PTB) patients detected by ECS with those detected by routine passive case finding (PCF).

METHODS

A cohort study using secondary program data conducted in Lahore, Faisalabad and Rawalpindi districts and Islamabad in 2013-15. We used log binomial regression models to assess if ECS was associated with unfavorable treatment outcomes (death, loss-to-follow-up, failure, not evaluated) after adjusting for potential confounders.

RESULTS

We included 79,431 people with PTB; 4604 (5.8%) were detected by ECS with 4052 (88%) bacteriologically confirmed. In all PTB patients the proportion with unfavorable outcomes was not significantly different in ECS group (9.6%) compared to PCF (9.9%), however, among bacteriologically confirmed patients unfavorable outcomes were significantly lower in ECS (9.9%) than PCF group (11.6%, P = 0.001). ECS was associated with a lower risk of unfavorable outcomes (adjusted relative risk (aRR) 0.90; 95% CI 0.82-0.99) among 'all PTB' patients and bacteriologically confirmed PTB patients (aRR 0.91; 95% CI 0.82-1.00).

CONCLUSION

In PTB patients detected by ECS the treatment outcomes were not inferior to those detected by PCF.

"I got tested at home, the help came to me": acceptability and feasibility of home-based TB testing of household contacts using portable molecular diagnostics in South Africa

OBJECTIVE

The effectiveness of household contact investigations is limited by low referral uptake for clinic-based TB testing by symptomatic household contacts. We qualitatively investigated the acceptability and perceived benefits of home-based TB testing using a portable GeneXpert-I instrument (GX-I) in an urban South African township.

METHODS

In-depth interviews were conducted with household contacts tested and those that observed testing. Semi-structured interviews explored household contact's understanding of TB, perceptions of the GX-I device and testing procedures, confidentiality, willingness to refer others, and views on home- vs. clinic-based testing. Focus group discussions with home-based TB testing implementing staff assessed operational considerations for scale-up. Data were analysed using a constant comparison approach to qualitatively evaluate the acceptability and feasibility of home-based TB testing.

RESULTS

Thirty in-depth interviews and two focus group discussions were conducted. Observing one's own sputum being tested resulted in an emergent trust in home-based TB testing, the GX-I device and one's test results. Home-based TB testing was considered convenient, helped to overcome apathy towards testing and mitigated barriers to clinic-based testing. Perceptions that home-based TB testing contributes to improved household and community health resulted in an emergent theme of alleviation of health insecurities. Operational concerns regarding inadvertent disclosure of one's diagnosis to household members and time spent in people's homes were identified.

CONCLUSIONS

Home-based TB testing was acceptable and feasible. Individuals expressed belief in the machine by being able to witness the testing process. Though most themes mirrored qualitative studies of home-based HIV testing, the alleviation of health insecurities theme is unique to home-based TB testing. Future research must evaluate the impact of home-based TB testing on case finding yield, time-to-treatment initiation and household outcomes.

The TB REACH Initiative: Supporting TB Elimination Efforts in the Asia-Pacific

After many years of TB 'control' and incremental progress, the TB community is talking about ending the disease, yet this will only be possible with a shift in the way we approach the TB response. While the Asia-Pacific region has the highest TB burden worldwide, it also has the opportunity to lead the quest to end TB by embracing the four areas laid out in this series: using data to target hotspots, initiating active case finding, provisioning preventive TB treatment, and employing a biosocial approach. The Stop TB Partnership's TB REACH initiative provides a platform to support partners in the development, evaluation and scale-up of new and innovative technologies and approaches to advance TB programs. We present several approaches TB REACH is taking to support its partners in the Asia-Pacific and globally to advance our collective response to end TB.

Islands of Tuberculosis Elimination: An Evaluation of Community-Based Active Case Finding in North Sumatra, Indonesia

Community-based active case finding (ACF) is needed to reach key/vulnerable populations with limited access to tuberculosis (TB) care. Published reports of ACF interventions in Indonesia are scarce. We conducted an evaluation of a multicomponent community-based ACF intervention as it scaled from one district to nine in Nias and mainland North Sumatra. Community and health system support measures including laboratory strengthening, political advocacy, sputum transport, and community awareness were instituted. ACF was conducted in three phases: pilot (18 months, 1 district), intervention (12 months, 4 districts) and scale-up (9 months, 9 districts). The pilot phase identified 215 individuals with bacteriologically positive (B+) TB, representing 42% of B+ TB notifications. The intervention phase yielded 509, representing 54% of B+ notifications and the scale-up phase identified 1345 individuals with B+ TB (56% of notifications). We observed large increases in B+ notifications on Nias, but no overall change on the mainland despite district variation. Overall, community health workers screened 377,304 individuals of whom 1547 tested positive, and 95% were initiated on treatment. Our evaluation shows that multicomponent community-based ACF can reduce the number of people missed by TB programs. Community-based organizations are best placed for accessing and engaging hard to reach populations and providing integrated support which can have a large positive effect on TB notifications.

Excess Risk of Tuberculous Infection among Extra-Household Contacts of Tuberculosis Cases in an African City

RATIONALE

Although households of tuberculosis cases represent a setting for intense transmission of M. tuberculosis, household exposure accounts for less than 20% of transmission within a community.

OBJECTIVES

To estimate excess risk of M. tuberculosis infection among household and extra-household contacts of index cases.

METHODS

We performed a cross-sectional study in Kampala, Uganda, to delineate social networks of tuberculosis cases and matched controls without tuberculosis. We estimated the age-stratified prevalence difference of tuberculous infection between case and control networks, partitioned as household and extra-household contacts.

RESULTS

We enrolled 123 index cases, 124 index controls, and 2415 first-degree network contacts. The prevalence of infection was highest among household contacts of cases (61.5%), lowest among household contacts of controls (25.2%), and intermediary among extra-household tuberculosis contacts (44.9%) and extra-household control contacts (41.2%). The age-adjusted prevalence difference between extra-household contacts of cases and their controls was 5.4%. The prevalence of infection was similar among the majority of extra-household case contacts and corresponding controls (47%).

CONCLUSIONS

Most first-degree social network members of tuberculosis cases do not have adequate contact with the index case to experience additional risk for infection but appear instead to acquire infection through unrecognized exposures with infectious cases in the community.

Tuberculosis in migrants - screening, surveillance and ethics

Tuberculosis (TB) is the leading infectious cause of human mortality and is responsible for nearly 2 million deaths every year. It is often regarded as a 'silent killer' because it predominantly affects the poor and marginalized, and disease outbreaks occur in 'slow motion' compared to Ebola or coronavirus 2 (COVID-19). In low incidence countries, TB is predominantly an imported disease and TB control in migrants is pivotal for countries to progress towards TB elimination in accordance with the World Health Organisations (WHO's) End TB strategy. This review provides a brief overview of the different screening approaches and surveillance processes that are in place in low TB incidence countries. It also includes a detailed discussion of the ethical issues related to TB screening of migrants in these settings and the different interests that need to be balanced. Given recognition that a holistic approach that recognizes and respects basic human rights is required to end TB, the review considers the complexities that require consideration in low-incidence countries that are aiming for TB elimination.

Estimating the yield of tuberculosis from key populations to inform targeted interventions in South Africa: a scoping review

Introduction

Tuberculosis (TB) case finding strategies are recommended to increase yield for TB in key populations. Several key populations are identified in the literature, but techniques for estimating yield and prioritising interventions are needed.

Methods

We conducted a scoping review of existing evidence on TB burden to assess contribution of key populations to the TB epidemic in South Africa. Reports, articles and conference abstracts from January 2000 to December 2016 were reviewed to determine TB incidence, prevalence and size of key populations in South Africa. Meta-analysis summarised prevalence and incidence rates of TB in selected key populations assessed for heterogeneity. TB risk was calculated for each key population. Number needed to screen (NNS) to diagnose one case of TB disease was computed. Population attributable fraction estimated the potential impact of interventions on TB cases per population.

Results

The search yielded 140 citations, of which 49 were included in the review and a final 32 were included in the meta-analysis. A high prevalence of TB disease was observed in HIV-infected patients with an estimated effect size (ES=0.25, 95% CI 0.20 to 0.30). Heterogeneity was high in this population (I²=94.8%, p value=0.000). The highest incidence rate of TB disease was observed in the HIV-infected population (ES=6.07, 95% CI 4.90 to 7.51). The risk of TB disease in South Africa was high in informal settlements (RR=5.8), HIV-infected (RR=5.4) and inmates (RR=5.0). Most cases of TB would be found in inmates (NNS=26) and household contacts of patients with TB (NNS=25). A larger impact would be observed if interventions are directed towards inmates (31%), people living with HIV (PLHIV (37%) and informal settlements (43%).

Conclusions

Our findings illustrate the of value using available epidemiological evidence to inform targeted TB interventions. This review suggests that targeting interventions towards inmates, PLHIV and informal settlements would have a bigger impact on TB burden in South Africa.

Longer Delays in Diagnosis and Treatment of Pulmonary Tuberculosis in Pastoralist Setting, Eastern Ethiopia

Purpose

This study aimed to assess the extent of patient, health system and total delays in diagnosis and treatment of pulmonary tuberculosis (TB) in Somali pastoralist setting, Ethiopia.

Patients and Methods

A cross-sectional study among 444 confirmed new pulmonary TB patients aged ≥15 years in 5 TB care units was conducted between December 2017 and October 2018. Data were collected using a structured questionnaire and record review. We measured delays from symptom onset to provider visit, provider visit to diagnosis and diagnosis to treatment initiation. Delays were summarized using median days. Mann–Whitney and Kruskal–Wallis tests were used to compare delays between categories of explanatory variables. The Log-binomial regression model was used to reveal factors associated with health system delay ≥15 days, presented in adjusted prevalence ratio (APR) with 95% confidence interval (CI).

Results

The median age of patients was 30 years, ranged from 15 to 82. The majority (62.4%) were male, and nearly half (46.4%) were pastoralists. The median patient, health system and total delays were 30 (19–48.5), 14 (4.5–29.5) and 50 (35–73.5) days, respectively. The median patient delay (35.5 days) and total delay (58.5 days) among pastoralists were substantially higher than the equivalent delays among non-pastoralists [p<0.001]. Of all, 3.8% of patients (16 of 18 were pastoralists) delayed longer than 6 months without initiating treatment. Factors associated with health system delay ≥15 days were mild symptoms [APR (95% CI) = 1.4 (1.1–1.7)], smear-negativity [APR (95% CI) = 1.2 (1.01–1.5)], first visit to health centers [APR (95% CI) = 1.6 (1.3–2.0)] and multiple provider contacts [APR (95% CI) = 5.8 (3.5–9.6)].

Conclusion

Delay in diagnosis and treatment remains a major challenge of tuberculosis control targets in pastoralist settings of Ethiopia. Efforts to expand services tailored to transhumance patterns and diagnostic capacity of primary healthcare units need to be prioritized.

Household contact investigation for the detection of tuberculosis in Vietnam: economic evaluation of a cluster-randomised trial

BACKGROUND

Active case finding is recommended as an important strategy to control tuberculosis, particularly in low-income and middle-income countries with a high prevalence of the disease. However, the costs and cost-effectiveness of active case finding are unclear due to the absence of evidence from randomised trials. We assessed the costs and cost-effectiveness of an active case finding strategy in Vietnam, where there is a high prevalence of tuberculosis.

METHODS

We conducted an economic evaluation alongside the Active Case Finding in Tuberculosis (ACT2) trial-a pragmatic cluster-randomised controlled trial in 70 districts across eight provinces of Vietnam. Patients aged 15 years and older with smear-positive pulmonary tuberculosis were recruited to the trial if they lived with one or more other household members. Household contacts were verbally invited to the clinic by the index patient with tuberculosis. ACT2 compared a combination of active and passive case finding with usual care (passive case finding) of household contacts of patients with tuberculosis from a health system perspective. Clustering occurred at the district and household level. Districts were the unit of randomisation, and we used minimisation to ensure balance of intervention and control districts within each province. In the intervention group, participants were invited to attend screening at baseline, 6 months, 12 months, and 24 months. We determined health-care costs with a standardised national costing survey and reported results in 2017 $US. The primary outcome of our study was disability-adjusted life years (DALYs) averted over a 24-month period. ACT2 was registered prospectively with the Australian and New Zealand Clinical Trials Registry, number ACTRN126.100.00600044.

FINDINGS

Between Aug 11, 2010, and Aug 11, 2015, 10 964 index patients and 25 707 household contacts completed the ACT2 study. There were 10 069 household contacts in the intervention group and 15 638 household contacts in the control group. The incremental cost-effectiveness ratio per DALY averted was $544 (330-1375).

INTERPRETATION

Active case finding was shown to be highly cost-effective in a setting with a high prevalence of tuberculosis. Investment in the wide-scale implementation of this programme in Vietnam should be strongly supported.

FUNDING

Australian National Health and Medical Research Council.

Tuberculosis in children: screening, diagnosis and management

PURPOSE OF REVIEW

The present review focuses on recent advances and current challenges in screening, diagnosis and management of tuberculosis (TB) in children, encompassing TB infection and TB disease, and public health priorities for screening and family engagement.

RECENT FINDINGS

Although awareness has improved in recent years that children in TB endemic areas suffer a huge disease burden, translation into better prevention and care remains challenging. Recent WHO guidelines have incorporated screening of all household contacts of pulmonary TB cases, but implementation in high incidence settings remains limited. Improved tests using noninvasive samples, such as the lateral flow urinary lipoarabinomannan assay and the new Xpert Ultra assay applied to induced sputum or stool in young children, are showing promise and further assessment is eagerly awaited. From a treatment perspective, child-friendly dispersible fixed dose combination tablets are now widely available with excellent acceptability and tolerance reported in young children.

SUMMARY

High-level government commitment to TB control as a public health priority and feasible strategies to achieve this are required to contain the global epidemic, whereas strong engagement of local TB clinics and affected families in TB prevention is essential to limit secondary cases and protect exposed children.