Estimation of subnational tuberculosis burden: generation and application of a new tool in Indonesia

Clinical and economic burden of drug-susceptible tuberculosis in Indonesia: national trends 2017-19

BACKGROUND

The global incidence of tuberculosis is decreasing, yet it remains high in Indonesia. The Indonesian National Tuberculosis Program facilitates mandatory notification, which enables early detection and treatment, minimises complications, prevents transmission, and decreases deaths. This study aimed to assess the characteristics, trends, and economic burden of notified drug-susceptible tuberculosis cases registered in this system from 2017 to 2019.

METHODS

We performed a multiyear cross-sectional study focusing on drug-susceptible tuberculosis notified cases, incidence, geographical tuberculosis case distribution, treatment outcomes, and costs in Indonesia using data from Sistem Informasi Tuberkulosis (2017-19). The settings were Indonesian health-care facilities that provide tuberculosis control programmes and services. Eligible patients were those who were diagnosed with drug-susceptible tuberculosis and notified to Sistem Informasi Tuberkulosis.

FINDINGS

Between 2017 and 2019, notified cases increased from 429 219 to 523 614 individuals, corresponding to an increase in incidence from 167 cases per 100 000 to 196 cases per 100 000. In 2019, more than 250 cases per 100 000 inhabitants were notified in Jakarta, North Sulawesi, Gorontalo, and Papua. Treatment success rate increased from 363 098 (84·60%) of 429 219 in 2017 to 452 966 (86·51%) of 523 614 in 2019, with a relatively stable mortality, changing from 3·15% to 3·05%. HIV status was increasingly confirmed, with unknown status decreasing from 66·21% to 43·68%. The costs of visits and monitoring and drug regimens were relatively stable, with total direct medical costs slightly increasing from US$39·40 to $40·40 per case.

INTERPRETATION

Progress was made on drug-susceptible tuberculosis management in Indonesia. However, further intensified efforts, including case-finding, optimising diagnosis, and cost-effective tuberculosis management are required if Indonesia is to achieve the 2025 WHO End Tuberculosis Strategy target incidence of fewer than 55 cases per 100 000 people. These data are an important starting point for understanding drug-susceptible tuberculosis dynamics in Indonesia and optimising its management.

FUNDING

Directorate General of Higher Education; Ministry of Education, Culture, Research, and Technology of the Republic of Indonesia.

The prevalence and risk factors for tuberculosis among healthcare workers in Yogyakarta, Indonesia

Healthcare workers (HCWs) are at risk of contracting TB, particularly when in high tuberculosis (TB) burden settings. Routine surveillance data and evidence are limited on the burden of TB amongst HCWs in Indonesia. We aimed to measure the prevalence of TB infection (TBI) and disease among HCWs in four healthcare facilities in Yogyakarta province in Indonesia, and explore risk factors for TBI. A cross-sectional TB screening study targeted all HCWs from four pre-selected facilities (1 hospital, 3 primary care) in Yogyakarta, Indonesia. Voluntary screening included symptom assessment, Chest X-ray (CXR), Xpert MTB/RIF (if indicated) and tuberculin skin test (TST). Analyses were descriptive and included multivariable logistic regression. Of 792 HCWs, 681 consented (86%) to the screening; 59% (n = 401) were female, 62% were medical staff (n = 421), 77% worked in the one participating hospital (n = 524), and the median time working in the health sector was 13 years (IQR: 6-25 years). Nearly half had provided services for people with TB (46%, n = 316) and 9% reported ever having TB (n = 60). Among participants with presumptive TB (15%, n = 99/662), none were diagnosed microbiologically or clinically with active TB disease. TBI was detected in 25% (95% CI: 22-30; n = 112/441) of eligible HCWs with a TST result. A significant association was found between TB infection and being male (adjusted Odds Ratio (aOR) 2.02 (95%CI: 1.29-3.17)), currently working in the participating hospital compared to primary care (aOR 3.15 (95%CI: 1.75-5.66)), and older age (1.05 OR increase per year of life between 19-73 years (95%CI: 1.02-1.06)). This study supports prioritisation of HCWs as a high-risk group for TB infection and disease, and the need for comprehensive prevention and control programs in Indonesia. Further, it identifies characteristics of HCWs in Yogyakarta at higher risk of TBI, who could be prioritised in screening programs if universal coverage of prevention and control measures cannot be achieved.

Finding gaps in routine TB surveillance activities in Bangladesh

BACKGROUND :

TB was the leading cause of death from a single infectious pathogen globally between 2014 and 2019. Fine-scale estimates of TB prevalence and case notifications can be combined to guide priority-setting for strengthening routine surveillance activities in high-burden countries. We produce policy-relevant estimates of the TB epidemic at the second administrative unit in Bangladesh.

METHODS :

We used a Bayesian spatial framework and the cross-sectional National TB Prevalence Survey from 2015–2016 in Bangladesh to estimate prevalence by district. We used case notifications to calculate prevalence-to-notification ratio, a key metric of under-diagnosis and under-reporting.

RESULTS :

TB prevalence rates were highest in the north-eastern districts and ranged from 160 cases per 100,000 (95% uncertainty interval [UI] 80–310) in Jashore to 840 (UI 690–1020) in Sunamganj. Despite moderate prevalence rates, the Rajshahi and Dhaka Divisions presented the highest prevalence-to-notification ratios due to low case notifications. Resolving subnational disparities in case detection could lead to 26,500 additional TB cases (UI 8,500–79,400) notified every year.

CONCLUSION :

This study is the first to produce and map subnational estimates of TB prevalence and prevalence-to-notification ratios, which are essential to target prevention and treatment efforts in high-burden settings. Reaching TB cases currently missing from care will be key to ending the TB epidemic.

A spatial-mechanistic model to estimate subnational tuberculosis burden with routinely collected data: An application in Brazilian municipalities

Reliable subnational estimates of TB incidence would allow national policy makers to focus disease control resources in areas of highest need. We developed an approach for generating small area estimates of TB incidence, and the fraction of individuals missed by routine case detection, based on available notification and mortality data. We demonstrate the feasibility of this approach by creating municipality-level burden estimates for Brazil. We developed a mathematical model describing the relationship between TB incidence and TB case notifications and deaths, allowing for known biases in each of these data sources. We embedded this model in a regression framework with spatial dependencies between local areas, and fitted the model to municipality-level case notifications and death records for Brazil during 2016-2018. We estimated outcomes for 5568 municipalities. Incidence rate ranged from 8.6 to 57.2 per 100,000 persons/year for 90% of municipalities, compared to 44.8 (95% UI: 43.3, 46.8) per 100,000 persons/year nationally. Incidence was concentrated geographically, with 1% of municipalities accounting for 50% of incident TB. The estimated fraction of incident TB cases receiving diagnosis and treatment ranged from 0.73 to 0.95 across municipalities (compared to 0.86 (0.82, 0.89) nationally), and the rate of untreated TB ranged from 0.8 to 72 cases per 100,000 persons/year (compared to 6.3 (4.8, 8.3) per 100,000 persons/year nationally). Granular disease burden estimates can be generated using routine data. These results reveal substantial subnational differences in disease burden and other metrics useful for designing high-impact TB control strategies.

Global Tuberculosis Report 2020 - Reflections on the Global TB burden, treatment and prevention efforts

The October 2020 Global TB report reviews TB control strategies and United Nations (UN) targets set in the political declaration at the September 2018 UN General Assembly high-level meeting on TB held in New York. Progress in TB care and prevention has been very slow. In 2019, TB remained the most common cause of death from a single infectious pathogen. Globally, an estimated 10.0 million people developed TB disease in 2019, and there were an estimated 1.2 million TB deaths among HIV-negative people and an additional 208, 000 deaths among people living with HIV. Adults accounted for 88% and children for 12% of people with TB. The WHO regions of South-East Asia (44%), Africa (25%), and the Western Pacific (18%) had the most people with TB. Eight countries accounted for two thirds of the global total: India (26%), Indonesia (8.5%), China (8.4%), the Philippines (6.0%), Pakistan (5.7%), Nigeria (4.4%), Bangladesh (3.6%) and South Africa (3.6%). Only 30% of the 3.5 million five-year target for children treated for TB was met. Major advances have been development of new all oral regimens for MDRTB and new regimens for preventive therapy. In 2020, the COVID-19 pandemic dislodged TB from the top infectious disease cause of mortality globally. Notably, global TB control efforts were not on track even before the advent of the COVID-19 pandemic. Many challenges remain to improve sub-optimal TB treatment and prevention services. Tuberculosis screening and diagnostic test services need to be ramped up. The major drivers of TB remain undernutrition, poverty, diabetes, tobacco smoking, and household air pollution and these need be addressed to achieve the WHO 2035 TB care and prevention targets. National programs need to include interventions for post-tuberculosis holistic wellbeing. From first detection of COVID-19 global coordination and political will with huge financial investments have led to the development of effective vaccines against SARS-CoV2 infection. The world now needs to similarly focus on development of new vaccines for TB utilizing new technological methods.

Variation of tuberculosis prevalence across diagnostic approaches and geographical areas of Indonesia

Background

Tuberculosis (TB) has contributed to a significant disease burden and economic loss worldwide. Given no gold standard for diagnosis, early identification of TB infection has been challenging. This study aimed to comparatively investigate the prevalence of TB across diagnostic approaches (sputum AFB, sputum culture, sputum genetic test, and chest x-ray) and geographical areas of Indonesia.

Methods

Participant demographic variables and TB screening test results were obtained from the Tuberculosis Unit, Health Research and Development Agency, Ministry of Health (HRDA-MoH). The prevalence of pulmonary TB in populations aged 15 years and over was calculated using TB cases as a numerator and populations aged 15 years and over as a denominator. Variations across geographical areas and diagnostic approaches were expressed as prevalence and 95% confidence interval (CI).

Results

A total of 67,944 records were reviewed. Based on bacteriological evidence, the prevalence of TB per 100,000 in Indonesia was 759 (95% CI: 589.7–960.8) with variations across areas: 913 (95% CI 696.7–1,176.7; Sumatra), 593 (95% CI 447.2–770.6; Java-Bali), and 842 (95% CI 634.7–1,091.8; other islands). Also, the prevalence of TB varied across diagnostic approaches: 256.5 (sputum AFB), 545 (sputum culture), 752.2 (chest x-ray), and 894.9 (sputum genetic test). Based on sputum AFB, the TB prevalence varied from 216.6 (95% CI 146.5–286.8; Java-Bali), 259.9 (95% CI 184.2–335.6; other islands) to 307.4 (95% CI 208.3–406.5; Sumatra). Based on sputum culture, the TB prevalence ranged from 487.9 (95% CI 433.6–548.6; Java-Bali), 635.9 (95% CI 564.9–715.1; Sumatra), to 2,129.8 (95% CI 1,664.0–2,735.6; other islands). Based on chest x-ray, the TB prevalence varied from 152.1 (95% CI 147.9–156.3; Java-Bali), 159.2 (95% CI 154.1–164.3; Sumatra), to 864 (95% CI 809–921.4; other islands). Based on sputum genetic test, the TB prevalence ranged from 838.7 (95% CI 748.4–900.8; Java-Bali), 875 (95% CI 775.4–934.2; Sumatra), to 941.2 (95% CI 663.6–992.3; other islands).

Conclusions

The variation of TB prevalence across geographical regions could be confounded by the diagnostic approaches.

Trial registration

This study was approved by the Institutional Review Board of Chulalongkorn University (IRB No. 684/63).