Towards tuberculosis elimination: an action framework for low-incidence countries

Perspectives of Vietnamese, Sudanese and South Sudanese immigrants on targeting migrant communities for latent tuberculosis screening and treatment in low-incidence settings: A report on two Victorian community panels

BACKGROUND

Tuberculosis (TB) elimination strategies in Australia require a focus on groups who are at highest risk of TB infection, such as immigrants from high-burden settings. Understanding attitudes to different strategies for latent TB infection (LTBI) screening and treatment is an important element of justifiable elimination strategies.

METHOD

Two community panels were conducted in Melbourne with members of the Vietnamese (n = 11), Sudanese and South Sudanese communities (n = 9). Panellists were provided with expert information about LTBI and different screening and health communication strategies, then deliberated on how best to pursue TB elimination in Australia.

FINDINGS

Both panels unanimously preferred LTBI screening to occur pre-migration rather than in Australia. Participants were concerned that post-migration screening would reach fewer migrants, noted that conducting LTBI screening in Australia could stigmatize participants and that poor awareness of LTBI would hamper participation. If targeted screening was to occur in Australia, the Vietnamese panel preferred 'place-based' communication strategies, whereas the Sudanese and South Sudanese panel emphasized that community leaders should lead communication strategies to minimize stigma. Both groups emphasized the importance of maintaining community trust in Australian health service providers, and the need to ensure targeting did not undermine this trust.

CONCLUSION

Pre-migration screening was preferred. If post-migration screening is necessary, the potential for stigma should be reduced, benefit and risk profile clearly explained and culturally appropriate communication strategies employed. Cultural attitudes to health providers, personal health management and broader social vulnerabilities of targeted groups need to be considered in the design of screening programs.

Confronting structural racism in the prevention and control of tuberculosis in the United States

Tuberculosis incidence in the United States is declining, yet projections indicate that we will not eliminate tuberculosis in the 21 st century. Incidence rates in regions serving the rural and urban poor, including recent immigrants, are well above the national average. People experiencing incarceration and homelessness represent additional key populations. Better engagement of marginalized populations will not succeed without first addressing the structural racism that fuels continued transmission. Examples include: (1) systematic underfunding of contact tracing in health departments serving regions where Black, Indigenous, and People of Color (BIPOC) live; (2) poor access to affordable care in state governments that refuse to expand insurance coverage to low-income workers through the Affordable Care Act; (3) disproportionate incarceration of BIPOC into crowded prisons with low tuberculosis screening rates; and (4) fear-mongering among immigrants that discourages them from accessing preventive health services. To eliminate tuberculosis, we must first eliminate racist policies that limit essential health services in vulnerable communities.

Preventing tuberculosis in children: A global health emergency

It is estimated that 20 million children are exposed to tuberculosis (TB) each year, making TB a global paediatric health emergency. TB preventative efforts have long been overlooked. With the view of achieving "TB elimination" in "our lifetime", this paper explores challenges and potential solutions in the TB prevention cascade, including identifying children who have been exposed to TB; detecting TB infection in these children; identifying those at highest risk of progressing to disease; implementing treatment of TB infection; and mobilizing multiple stakeholders support to successfully prevent TB.

Tuberculosis among Newly Arrived Immigrants and Refugees in the United States

Rationale: U.S. health departments routinely conduct post-arrival evaluation of immigrants and refugees at risk for tuberculosis (TB), but this important intervention has not been thoroughly studied.Objectives: To assess outcomes of the post-arrival evaluation intervention.Methods: We categorized at-risk immigrants and refugees as having had recent completion of treatment for pulmonary TB disease overseas (including in Mexico and Canada); as having suspected TB disease (chest radiograph/clinical symptoms suggestive of TB) but negative culture results overseas; or as having latent TB infection (LTBI) diagnosed overseas. Among 2.1 million U.S.-bound immigrants and refugees screened for TB overseas during 2013-2016, 90,737 were identified as at risk for TB. We analyzed a national data set of these at-risk immigrants and refugees and calculated rates of TB disease for those who completed post-arrival evaluation.Results: Among 4,225 persons with recent completion of treatment for pulmonary TB disease overseas, 3,005 (71.1%) completed post-arrival evaluation within 1 year of arrival; of these, TB disease was diagnosed in 22 (732 cases/100,000 persons), including 4 sputum culture-positive cases (133 cases/100,000 persons), 13 sputum culture-negative cases (433 cases/100,000 persons), and 5 cases with no reported sputum-culture results (166 cases/100,000 persons). Among 55,938 with suspected TB disease but negative culture results overseas, 37,089 (66.3%) completed post-arrival evaluation; of these, TB disease was diagnosed in 597 (1,610 cases/100,000 persons), including 262 sputum culture-positive cases (706 cases/100,000 persons), 281 sputum culture-negative cases (758 cases/100,000 persons), and 54 cases with no reported sputum-culture results (146 cases/100,000 persons). Among 30,574 with LTBI diagnosed overseas, 18,466 (60.4%) completed post-arrival evaluation; of these, TB disease was diagnosed in 48 (260 cases/100,000 persons), including 11 sputum culture-positive cases (60 cases/100,000 persons), 22 sputum culture-negative cases (119 cases/100,000 persons), and 15 cases with no reported sputum-culture results (81 cases/100,000 persons). Of 21,714 persons for whom treatment for LTBI was recommended at post-arrival evaluation, 14,977 (69.0%) initiated treatment and 8,695 (40.0%) completed treatment.Conclusions: Post-arrival evaluation of at-risk immigrants and refugees can be highly effective. To optimize the yield and impact of this intervention, strategies are needed to improve completion rates of post-arrival evaluation and treatment for LTBI.

High yield from repeated testing for tuberculosis among high-risk citizens in Denmark

BACKGROUND

Screening for TB (tuberculosis) among socially marginalized citizens has been implemented in many urban areas in countries with a low incidence of TB, including Denmark. This study aims to describe the findings of the screening programs for TB and latent tuberculosis (LTBI) used in the western part of Denmark in the period 2014-2019.

METHODS

Data was collected retrospectively on test results from interferon-gamma release assays (IGRA), spot sputum tests and chest X-rays performed as part of TB and LTBI screening among 1024 socially marginalized citizens in urban areas of western Denmark in 2014-2019.

RESULTS

The overall TB incidence was 2148/100.000 and number needed to screen to find one TB case was 39. The incidence of LTBI in the group screened using IGRA was 17.500/100.000. TB incidence when using spot sputum test was 2.5, while TB incidence when using IGRA as the primary screening test was 2.7. In total, 38.9% of TB diagnoses were obtained after the second or third round of screening.

CONCLUSION

We demonstrated a high incidence of TB and LTBI among socially marginalized citizens in Denmark. Screening with spot sputum testing and IGRA generated comparable results in diagnosing TB in this setting.

Knowledge, attitudes, beliefs, and stigma related to latent tuberculosis infection: a qualitative study among Eritreans in the Netherlands

Background

Tailored and culturally appropriate latent tuberculosis (TB) infection screening and treatment programs, including interventions against TB stigma, are needed to reduce TB incidence in low TB incidence countries. However, we lack insights in stigma related to latent TB infection (LTBI) among target groups, such as asylum seekers and refugees. We therefore studied knowledge, attitudes, beliefs, and stigma associated with LTBI among Eritrean asylum seekers and refugees in the Netherlands.

Methods

We used convenience sampling to interview adult Eritrean asylum seekers and refugees: 26 semi-structured group interviews following TB and LTBI related health education and LTBI screening, and 31 semi-structured individual interviews with Eritreans during or after completion of LTBI treatment (November 2016–May 2018). We used a thematic analysis to identify, analyse and report patterns in the data.

Results

Despite TB/LTBI education, misconceptions embedded in cultural beliefs about TB transmission and prevention persisted. Fear of getting infected with TB was the cause of reported enacted (isolation and gossip) and anticipated (concealment of treatment and self-isolation) stigma by participants on LTBI treatment.

Conclusion

The inability to differentiate LTBI from TB disease and consequent fear of getting infected by persons with LTBI led to enacted and anticipated stigma comparable to stigma related to TB disease among Eritreans. Additional to continuous culturally sensitive education activities, TB prevention programs should implement evidence-based interventions reducing stigma at all phases in the LTBI screening and treatment cascade.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12889-020-09697-z.

Small-area level socio-economic deprivation and tuberculosis rates in England: An ecological analysis of tuberculosis notifications between 2008 and 2012

Background

Tuberculosis (TB) rates in England are among the highest in high-income countries. Poverty and historic and current immigration from high TB incidence parts of the world are two major drivers of tuberculosis in England. However, little has been done in recent years to examine socio-economic trends in TB rates in England, and to disentangle the role of deprivation from that of place of birth in the current TB epidemiology.

Objectives

To assess the association between England’s 2008–2012 TB notification rates and small area-level deprivation, together and separately in the UK-born and foreign-born populations.

Methods

Ecological analysis of the association between quintiles of England’s 2010 Index of Multiple Deprivation (IMD) and TB rates at the Lower-layer Super Output Area (LSOA; average population ~1500) level, using negative binomial and zero-inflated negative binomial regression models, adjusting for age, sex, urban/rural area classification, and area-level percentage of non-White residents.

Results

There was a log-linear gradient between area-deprivation levels and TB rates, with overall TB rates in the most deprived quintile areas three times higher than the least deprived quintile after adjustment for age and sex (IRR = 3.35; 95%CI: 3.16 to 3.55). The association and gradient were stronger in the UK-born than the foreign-born population, with UK-born TB rates in the most deprived quintiles about two-and-a-half times higher than the least deprived quintile (IRR = 2.39; 95%CI: 2.19 to 2.61) after controlling for age, sex, urban/rural classification and percentage of non-White residents; whereas the comparable figure for foreign-born persons was 80% higher (IRR = 1.78; 95%CI: 1.66 to 1.91).

Conclusions

Socio-economic deprivation continues to play a substantial role in sustaining the TB epidemic in England, especially in the UK-born population. This supports the case for further investigations of the underlying social- determinants of TB.

Using Bayesian spatial models to map and to identify geographical hotspots of multidrug-resistant tuberculosis in Portugal between 2000 and 2016

Multidrug-resistant tuberculosis (MDR-TB) is a major threat to the eradication of tuberculosis. TB control strategies need to be adapted to the necessities of different countries and adjusted in high-risk areas. In this study, we analysed the spatial distribution of the MDR- and non-MDR-TB cases across municipalities in Continental Portugal between 2000 and 2016. We used Bayesian spatial models to estimate age-standardized notification rates and standardized notification ratios in each area, and to delimitate high- and low-risk areas, those whose standardized notification ratio is significantly above or below the country’s average, respectively. The spatial distribution of MDR- and non-MDR-TB was not homogeneous across the country. Age-standardized notification rates of MDR-TB ranged from 0.08 to 1.20 and of non-MDR-TB ranged from 7.73 to 83.03 notifications per 100,000 population across the municipalities. We identified 36 high-risk areas for non-MDR-TB and 8 high-risk areas for MDR-TB, which were simultaneously high-risk areas for non-MDR-TB. We found a moderate correlation (ρ = 0.653; 95% CI 0.457–0.728) between MDR- and non-MDR-TB standardized notification ratios. We found heterogeneity in the spatial distribution of MDR-TB across municipalities and we identified priority areas for intervention against TB. We recommend including geographical criteria in the application of molecular drug resistance to provide early MDR-TB diagnosis, in high-risk areas.

Incidence of and risk factors for tuberculosis among people with HIV on antiretroviral therapy in the United Kingdom

Objective:

The United Kingdom has a low tuberculosis incidence and earlier combination antiretroviral therapy (cART) is expected to have reduced incidence among people with HIV. Epidemiological patterns and risk factors for active tuberculosis were analysed over a 20-year period among people accessing HIV care at sites participating in the UK CHIC observational study.

Design:

Cohort analysis.

Methods:

Data were included for individuals over 15 years old attending for HIV care between 1996 and 2017 inclusive, with at least 3 months follow-up recorded. Incidence rates of new tuberculosis events were calculated and stratified by ethnicity (white/Black/other) as a proxy for tuberculosis exposure. Poisson regression models were used to determine the associations of calendar year, ethnicity and other potential risk factors after cART initiation.

Results:

Fifty-eight thousand seven hundred and seventy-six participants (26.3% women; 54.5% white, 32.0% Black, 13.5% other/unknown ethnicity; median (interquartile range) age 34 (29–42) years) were followed for 546 617 person-years. Seven hundred and four were treated for active tuberculosis [rate 1.3; 95% confidence interval (CI) 1.2–1.4/1000 person-years). Tuberculosis incidence decreased from 1.3 (1.2–1.5) to 0.6 (0.4–0.9)/1000 person-years from pre-2004 to 2011–2017. The decline among people of Black ethnicity was less steep than among those of white/other ethnicities, with incidence remaining high among Black participants in the latest period [2.1 (1.4–3.1)/1000 person-years]. Two hundred and eighty-three participants [191 (67%) Black African] had tuberculosis with viral load less than 50 copies/ml.

Conclusion:

Despite the known protective effect of cART against tuberculosis, a continuing disproportionately high incidence is seen among Black African people. Results support further interventions to prevent tuberculosis in this group.

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.

Management of Tuberculosis: Are the Practices Homogeneous in High-Income Countries?

Objectives: To evaluate and compare practices regarding the diagnosis, isolation measures, and treatment of tuberculosis (TB) in high-income countries and mainly in Europe.

Materials and Methods: A survey was conducted from November 2018 to April 2019 within the European Society of Clinical Microbiology and Infectious Diseases Study Group for Mycobacterial Infections (ESGMYC). The practices observed were compared to the main international guidelines.

Results: Among 136 ESGMYC members, 64 (17 countries) responded to the questionnaire. In their practice, two (20.7%) or three sputum samples (79.3%) were collected for the diagnosis of pulmonary TB, alternatively induced sputum (n = 37, 67.2%), bronchoscopy (34, 58.6%), and gastric aspirates (15, 25.9%). Nucleic acid amplification tests (NAATs) were performed by 41 (64%) respondents whatever the smear result and by 47 (73%) in case of smear-positive specimens. NAAT and adenosine deaminase measurement were used for extrapulmonary TB diagnosis in 83.6 and 40.4% of cases, respectively. For isolation duration, 21 respondents (42.9%) were keeping isolation until smear negativity. An initial treatment without ethambutol was offered by 14% (n = 9) of respondents. Corticosteroid therapy, cerebrospinal fluid opening pressure testing, and repeated lumbar puncture were carried out for central nervous system TB by 79.6, 51.9, and 46.3% of the respondents, respectively. For patients with human immunodeficiency virus–TB coinfection, the preferred antiretroviral therapy included dolutegravir 50 mg twice a day (56.8%). Comparing with the recommendations of the main guidelines, the practices are not totally consistent.

Conclusion: This study shows heterogeneous practices, particularly for diagnosis, and isolation, although rapid molecular testing is implemented in most centers. More standardization might be needed.

Hospital inpatient care utilization among patients with tuberculosis, Republic of Ireland, 2015-2018

BACKGROUND

The Republic of Ireland (ROI) has a low incidence of TB. A reform of TB services in 2003 recommended that the delivery of care to patients with TB should primarily be in the outpatient setting, with limited indications for hospitalization. Three hospitals were designated as TB centres. Our aim was to describe the utilization of hospital inpatient care by patients with TB in the ROI.

METHODS

We searched public hospital coding data to identify discharges between 01/01/2015-31/12/18 where TB was the principal diagnosis. The cost of TB episodes of care was calculated using payment rules for public hospitals in the ROI.

RESULTS

We identified 1185 discharges with TB as the principal diagnosis. Of these, 68% (801/1185) were emergency episodes of care and 32% (384/1185) were elective. We estimate that 65.1% (818/1257) patients with TB notified in the ROI from 2015 to 2018 who had an episode of care in a public hospital was 65.1% (818/1257) and that 50.8% (639/1257) of those notified had an emergency episode of care. The estimated mean annual cost of TB inpatient care per year in the ROI from 2015 to 2018 was €2,638,828-2,955,047, with emergency episodes of care having a mean annual cost of €2,250,926-2,557,397 per year.

CONCLUSIONS

The burden of TB on hospital inpatient care in the Republic of Ireland is significant.

Latent Tuberculosis Infection Increases in Kidney Transplantation Recipients Compared With Transplantation Candidates: A Neglected Perspective in Tuberculosis Control

Background

The prevalence and incidence of latent tuberculosis infection (LTBI) in patients with kidney transplantation remain unclear.

Methods

In this prospective study, we enrolled kidney transplantation candidates (KTCs) and recipients (KTRs) from 2014 to 2018. We defined LTBI as a positive result of QuantiFERON-TB Gold In-tube (QFT). We analyzed the predictors for LTBI acquisition and followed up on QFT assay test for 2 years among those initially without LTBI.

Results

Of 425 patients enrolled, 305 (71.8%) patients belonged to the KTC group and 120 (28.2%) to the KTR group. The initial QFT showed positive results in 32 (10.5%) and 24 (20.0%) patients in the KTC and KTR groups, respectively (P = .009). The QFT response value in patients with LTBI was higher in the KTR group than in the KTC group (1.85 vs 1.06 IU/mL, P = .046). Multivariate logistic regression showed that old age, absence of bacillus Calmette–Guérin (BCG) scar, presence of donor-specific antibody, and KTR group were independent factors for positive LTBI. For participants with initial negative QFT, positive QFT conversion within a 2-year follow-up was higher after kidney transplantation (20%) than in KTCs (5.5%) (P = .034).

Conclusions

This study is the first cohort to follow up LTBI status in patients with kidney transplantation and shows its higher prevalence and incidence in KTRs. It indicates that surveillance of LTBI after renal transplantation is important. In addition to status of kidney transplantation, old age, no BCG vaccination, and positive donor-specific antibody are also positive predictors for LTBI.

Insights into culturally appropriate latent tuberculosis infection (LTBI) screening in NSW: perspectives of Indian and Pakistani migrants

OBJECTIVE

Latent tuberculosis (LTBI) case-finding and treatment are a focus of TB elimination in Australia. We sought the perspectives of migrants from two high-burden countries likely to be targeted by this strategy.

METHODS

To understand perceptions of migrant groups in Australia on LTBI screening, 28 in-depth interviews were conducted with Indian and Pakistani community members recruited purposively through local organisations in the Illawarra region, New South Wales. Drawing on local TB policy, data collected qualitatively was analysed using framework methodologies.

RESULTS

Australia's immigration system prioritises migrants of higher socioeconomic status. Participants supported elimination but perceived TB as a disease of the poor and not relevant to them. Lack of understanding of LTBI and sensitivity to being 'targeted' are further barriers to screening participation.

CONCLUSION

Information provision and targeting rationale are an essential preamble to LTBI screening. Migration appears to modify cultural attitudes to TB, but not significantly. Despite less stigma surrounding TB in Australian contexts, testing privacy and confidentiality, and limiting public identification of specific groups remain important to program acceptability. Implications for public health: Progress towards TB elimination can be enhanced by consulting with targeted communities, using existing networks for communication and service provision; emphasising prevention benefits.

Active Pulmonary Tuberculosis in Elderly Patients: A 2016-2019 Retrospective Analysis from an Italian Referral Hospital

Tuberculosis (TB) in the elderly (>65 years old) has increasingly become a global health problem. It has long been recognized that older people are vulnerable to developing tuberculosis. We retrospectively evaluated data from patients older than 65 years diagnosed with pulmonary TB admitted to the National Institute for Infectious Diseases L. Spallanzani, Rome, Italy, from 1 January 2016 to 31 December 2019. One hundred and six consecutive patients were diagnosed with pulmonary TB and 68% reported at least one comorbidity and 44% at least one of the TB risk-factors. Out of the 26 elderly patients who reported an adverse event, having risk factors for TB (O.R. (Odds Ratios) = 1.45; 95% CI 1.12-3.65) and the presence of cavities on Chest X-rays (O.R. = 1.42; 95% CI 1.08-2.73) resulted in being more likely to be associated with adverse events in elderly patients. Having weight loss (O.R. = 1.31; 95% CI 1.08-1.55) and dyspnea (O.R. = 1.23; 95% CI 1.13-1.41) resulted in being significant predictors of unsuccessful treatment outcome in elderly patients. Older people with TB represent a vulnerable group, with high mortality rate, with a challenging diagnosis. Hospitalizations in tertiary referral hospital with clinical expertise in TB management can be useful to improve the outcome of these fragile patients.

Health conditions of migrants landed in north-eastern Sicily and perception of health risks of the resident population

OBJECTIVES

In Italy, a recent irregular movement of people raised concerns among the host population on possible introduction of diseases that have long been controlled in the host countries. This study evaluates the health conditions of illegal immigrants landed on the north-eastern Sicilian territory, to provide information on the clinical and epidemiologic burden of infectious diseases among migrants and how the local population feel about these landings.

STUDY DESIGN

The study design is a cross-sectional study.

METHODS

The study considered all migrants landed illegally in the city of Messina, Sicily, between January 2014 and July 2018. Analysing the data of hospital admissions and disease notifications, we calculated the frequency of infectious diseases among migrant population. Furthermore, through a survey conducted by a well-known online newspaper, we analysed the perception that the local population has about the health risk represented by migrants.

RESULTS

In the considered five-year period, 108 landings, for a total of 38,608 migrants occurred at the Messina port. The percentage of hospitalisation was rather low (3.5%), and it concerned mainly pregnant women. The notifications of infectious diseases were contained, with exception of scabies and tuberculosis. Finally, from the online survey, resulted that there is a large part of local population that considers migrants a potential danger to community health.

CONCLUSIONS

Our data show that the presence of migrants should not have to date any impact on the health conditions of the resident population. However, monitoring over time the health of migrants and screening for infectious diseases as soon as possible after landing are advantageous for both migrants and host country.

Tuberculosis treatment outcomes of non-citizen migrants: Israel compared to other high-income countries

BACKGROUND

In TB low incidence countries, the outcome of TB treatment among non-citizen migrants from endemic countries affects ability to eliminate TB. This study compares TB treatment outcomes among non-citizen migrants in select pre-elimination country based on their policies for non-citizen migrant TB patients in order to determine how policy affects TB outcomes.

METHODS

A literature review was conducted via PUBMED, MEDLINE (2000-2017) on TB policy among non-citizen migrants and treatment outcome. Treatment outcome among migrants diagnosed in Israel during 2000-2014 was analysed.

RESULTS

In total, 18 publications met the inclusion criteria. All the countries reviewed except the United States offered free TB treatment to undocumented migrants. Successful TB treatment outcome for non-citizen migrants in Israel was 87%, the Netherlands was 90.7%, the UK was 82.1%, and outcomes in the US and Australia were not published.

CONCLUSIONS

There is a need to standardize results based on international definitions of migrants, asylum seekers, and refugees in order to determine status-specific barriers and to facilitate international comparisons. Policies insuring free access to TB care for non-citizen migrants are an important element for TB elimination in low incidence countries.

Comparison of QuantiFERON-TB Gold Plus, QuantiFERON-TB Gold In-Tube, and T-SPOT.TB among patients with tuberculosis

OBJECTIVES

This study evaluated the efficacy of the following interferon (IFN)-γ release assays (IGRAs): QuantiFERON-TB Gold Plus (QFT-Plus), QFT-Gold In-Tube (QFT-GIT), and T-SPOT. TB (T-SPOT) with the quantitative values of IFN-γ response.

METHODS

Blood samples were collected from patients with active tuberculosis (TB), latent TB infection (LTBI), individuals with previous TB infection, and healthy volunteers enrolled between May 2017 and June 2018.

RESULTS

IGRAs results were analyzed in 175 subjects (76 had active TB, 14 had LTBI, 35 had prior TB infection, and 50 were healthy). QFT-Plus and QFT-GIT revealed equal efficacy for IFN-γ values, and the IFN-γ response in QFTs tended to increase with the spot counts in T-SPOT, with similar high sensitivities (approximately 90%) in the active TB group. The test concordance of two of three IGRAs was optimal among all subjects (κ coefficients: 0.82-0.96). Additionally, the median quantitative values of IFN-γ with QFT-Plus and QFT-GIT were higher in the active TB group than in the LTBI and previous TB groups.

CONCLUSION

Three IGRAs showed equivalent efficacy with high sensitivities and higher IFN-γ response in active TB group than that in non-active TB group.

Isoniazid (INH) mono-resistance and tuberculosis (TB) treatment success: analysis of European surveillance data, 2002 to 2014

Introduction: Isoniazid (INH) is an essential drug for tuberculosis (TB) treatment. Resistance to INH may increase the likelihood of negative treatment outcome.

Aim: We aimed to determine the impact of INH mono-resistance on TB treatment outcome in the European Union/European Economic Area and to identify risk factors for unsuccessful outcome in cases with INH mono-resistant TB.

Methods: In this observational study, we retrospectively analysed TB cases that were diagnosed in 2002–14 and included in the European Surveillance System (TESSy). Multilevel logistic regression models were applied to identify risk factors and correct for clustering of cases within countries.

Results: A total of 187,370 susceptible and 7,578 INH mono-resistant TB cases from 24 countries were included in the outcome analysis. Treatment was successful in 74.0% of INH mono-resistant and 77.4% of susceptible TB cases. In the final model, treatment success was lower among INH mono-resistant cases (Odds ratio (OR): 0.7; 95% confidence interval (CI): 0.6–0.9; adjusted absolute difference in treatment success: 5.3%). Among INH mono-resistant TB cases, unsuccessful treatment outcome was associated with age above median (OR: 1.3; 95% CI: 1.2–1.5), male sex (OR: 1.3; 95% CI: 1.1–1.4), positive smear microscopy (OR: 1.3; 95% CI: 1.1–1.4), positive HIV status (OR: 3.3; 95% CI: 1.6–6.5) and a prior TB history (OR: 1.8; 95% CI: 1.5–2.2).

Conclusions: This study provides evidence for an association between INH mono-resistance and a lower likelihood of TB treatment success. Increased attention should be paid to timely detection and management of INH mono-resistant TB.

The diagnosis of latent tuberculosis infection (LTBI): currently available tests, future developments, and perspectives to eliminate tuberculosis (TB)

INTRODUCTION

Despite great efforts, tuberculosis (TB) is still a major public health threat worldwide. For decades, TB control programs have focused almost exclusively on infectious TB active cases.  However, it is evident that this strategy alone cannot achieve TB elimination. To achieve this objective a comprehensive strategy directed toward integrated latent tuberculosis infection (LTBI) management is needed. Recently it has been recognized that LTBI is not a stable condition but rather a spectrum of infections (e.g., intermittent, transient or progressive) which may lead to incipient, then subclinical, and finally active TB disease.

AIM

Provide an overview of current available LTBI diagnostic test including updates, future developments and perspectives.

RESULTS

There is currently no test for the direct identification of live MT infection in humans. The diagnosis of LTBI is indirect and relies on the detection of an immune response against MT antigens, assuming that the immune response has developed after a contact with the biological agent. Tuberculin skin test (TST) and interferon gamma release assays (IGRAs) are the main diagnostic tools for LTBI, however, both present strengths and limitations. The most ancient diagnostic test (TST) can be associated with several technical errors, has limited positive predictive value, is being influenced by BCG vaccination and several conditions can reduce the skin reactivity. Notwithstanding these limitations, prompt identification of TST conversion, should orientate indications for preventive therapy of LTBI. IGRAs have superior specificity, are not affected by M. bovis, BCG vaccination and other environmental mycobacteria. However, they present some logistical and organisational constraints and are more expensive. Currently, the WHO guidelines recommend that either a TST or an IGRA can be used to detect LTBI in high-income and upper middle-income countries with estimated TB incidences less than 100 per 100,000 population. Two skin tests (C-TB and Diaskintest), using only two specific M. tuberculosis antigens (ESAT-6 and CFP-10) instead of the tuberculin solution, have recently been developed but, to date, none of these tests is available on the European market.

CONCLUSION

Early identification and treatment of individuals with LTBI is an important priority for TB control in specific groups at risk within the population: this is of crucial meaning in recently infected cases both at the community level and in some occupational settings. Currently there is no gold standard test for LTBI: an improved understanding of the available tests is needed to develop better tools for diagnosing LTBI and predicting progression to clinical active disease.

Celebrating World Tuberculosis Day at the time of COVID-19

March 24th, the tuberculosis (TB) day, is the global call to raise awareness, celebrate successes and remind the world that TB is still the N°1 killer among the infectious causes of death [1]. TB is preventable and curable disease, and its control is a highly cost-effective health intervention. However, diagnostic delay and inadequate treatment contribute to the severity and mortality of the disease as well as the risk of transmission and development of drug resistance. Despite the fact that TB disproportionately impacts low- and middle- income countries, it does not spare any country in the world including those in the European Union/European Economic Area where more than 4000 of people still die for the disease every year [2]. Moreover, the high number of multidrug-resistant (MDR)-TB cases in some countries of the World Health Organization (WHO) European Region poses a growing public health threat. Despite the sheer numbers, TB has for too long been overshadowed by HIV and malaria, and currently by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the coronavirus disease 2019 (COVID-19) epidemic.

The annual risk of tuberculosis infection in newly hired researchers and healthcare workers using interferon-gamma release assay in Japan

The tuberculosis (TB) notification rate in Japan is gradually decreasing but has not yet achieved "pre-elimination," defined by the World Health Organization. To effectively tackle, control, and eliminate TB, estimating and monitoring the annual risk of TB infection (ARI) using tuberculin skin testing (TST) to understand the dynamics of TB epidemiology are significantly important. However, studies estimating ARIs using TST are few considering that Bacillus Calmette-Guérin vaccination coverage is high in Japan. This was a single-center, cross-sectional study conducted between January 2011 and December 2018 in Tokyo area where interferon-gamma release assays (IGRAs) were performed in newly hired researchers of Keio University School of Medicine and healthcare workers of Keio University Hospital to determine TB infection. We estimated the prevalence of TB infection and ARI based on their IGRA results. Among the 3908 subjects, 83 (2.124%) had positive IGRA results. Multiple logistic regression analysis revealed that age was a significant risk factor for positive IGRA result (adjusted odds ratio, 1.046). The ARIs were 0.049%-0.156% between 1986 and 2004, midyears of TB infection, but have not significantly decreased over approximately two decades. To decrease the risk of TB infection, advanced strategies to control and eliminate TB in Tokyo area are significantly required.

Post-Tuberculosis (TB) Treatment: The Role of Surgery and Rehabilitation

Even though the majority of tuberculosis (TB) programmes consider their work completed when a patient is ‘successfully’ cured, patients often continue to suffer with post-treatment or surgical sequelae. This review focuses on describing the available evidence with regard to the diagnosis and management of post-treatment and surgical sequelae (pulmonary rehabilitation). We carried out a non-systematic literature review based on a PubMed search using specific key-words, including various combinations of ‘TB’, ‘MDR-TB’, ‘XDR-TB’, ‘surgery’, ‘functional evaluation’, ‘sequelae’ and ‘pulmonary rehabilitation’. References of the most important papers were retrieved to improve the search accuracy. We identified the main areas of interest to describe the topic as follows: 1) ‘Surgery’, described through observational studies and reviews, systematic reviews and meta-analyses, IPD (individual data meta-analyses), and official guidelines (GRADE (Grading of Recommendations Assessment, Development and Evaluation) or not GRADE-based); 2) Post-TB treatment functional evaluation; and 3) Pulmonary rehabilitation interventions. We also highlighted the priority areas for research for the three main areas of interest. The collection of high-quality standardized variables would allow advances in the understanding of the need for, and effectiveness of, pulmonary rehabilitation at both the individual and the programmatic level. The initial evidence supports the importance of the adequate functional evaluation of these patients, which is necessary to identify those who will benefit from pulmonary rehabilitation.

Recent Highlights in Anti-infective Medicinal Chemistry from South Africa

Global advancements in biological technologies have vastly increased the variety of and accessibility to bioassay platforms, while simultaneously improving our understanding of druggable chemical space. In the South African context, this has resulted in a rapid expansion in the number of medicinal chemistry programmes currently operating, particularly on university campuses. Furthermore, the modern medicinal chemist has the advantage of being able to incorporate data from numerous related disciplines into the medicinal chemistry process, allowing for informed molecular design to play a far greater role than previously possible. Accordingly, this review focusses on recent highlights in drug-discovery programmes, in which South African medicinal chemistry groups have played a substantive role in the design and optimisation of biologically active compounds which contribute to the search for promising agents for infectious disease.

Treatment of Latent Tuberculosis Infection-An Update

Treatment of latent tuberculosis infection (LTBI) is an important component of TB control and elimination. LTBI treatment regimens include once-weekly isoniazid plus rifapentine for 3 months, daily rifampin for 4 months, daily isoniazid plus rifampin for 3-4 months, and daily isoniazid for 6-9 months. Isoniazid monotherapy is efficacious in preventing TB disease, but the rifampin- and rifapentine-containing regimens are shorter and have similar efficacy, adequate safety, and higher treatment completion rates. Novel vaccine strategies, host immunity-directed therapies and ultrashort antimicrobial regimens for TB prevention, such as daily isoniazid plus rifapentine for 1 month, are under evaluation.

Drug misuse, tobacco smoking, alcohol and other social determinants of tuberculosis in UK-born adults in England: a community-based case-control study

Addressing social determinants of tuberculosis (TB) is essential to achieve elimination, including in low-incidence settings. We measured the association between socio-economic status and intermediate social determinants of health (SDHs, including drug misuse, tobacco smoking and alcohol), and TB, taking into account their clustering in individuals. We conducted a case-control study in 23–38 years old UK-born White adults with first tuberculosis episode, and randomly selected age and sex frequency-matched community controls. Data was collected on education, household overcrowding, tobacco smoking, alcohol and drugs use, and history of homelessness and prison. Analyses were done using logistic regression models, informed by a formal theoretical causal framework (Directed Acyclic Graph). 681 TB cases and 1183 controls were recruited. Tuberculosis odds were four times higher in subjects with education below GCSE O-levels, compared to higher education (OR = 3.94; 95%CI: 2.74, 5.67), after adjusting for other TB risk factors (age, sex, BCG-vaccination and stays ≥3 months in Africa/Asia). When simultaneously accounting for respective SDHs, higher tuberculosis risk was independently associated with tobacco smoking, drugs use (especially injectable drugs OR = 5.67; 95%CI: 2.68, 11.98), homelessness and area-level deprivation. Population Attributable Fraction estimates suggested that tobacco and class-A drug use were, respectively, responsible for 18% and 15% of TB cases in this group. Our findings suggest that socio-economic deprivation remains a driver of tuberculosis in England, including through drugs misuse, tobacco smoking, and homelessness. These findings further support the integration of health and social services in high-risk young adults to improve TB control efforts.

Treatment with isoniazid or rifampin for latent tuberculosis infection: population-based study of hepatotoxicity, completion and costs

Clinical trials suggest less hepatotoxicity and better adherence with 4 months rifampin (4R) versus 9 months isoniazid (9H) for treating latent tuberculosis infection (LTBI). Our objectives were to compare frequencies of severe hepatic adverse events and treatment completion, and direct health system costs of LTBI regimens 4R and 9H, in the general population of the province of Quebec, Canada, using provincial health administrative data.Our retrospective cohort included all patients starting rifampin or isoniazid regimens between 2003 and 2007. We estimated hepatotoxicity from hospitalisation records, treatment completion from community pharmacy records and direct costs from billing records and fee schedules. We compared rifampin to isoniazid using logistic (hepatotoxicity), log-binomial (completion), and gamma (costs) regression, with adjustment for age, co-morbidities and other confounders.10 559 individuals started LTBI treatment (9684 isoniazid; 875 rifampin). Rifampin patients were older with more baseline co-morbidities. Severe hepatotoxicity risk was higher with isoniazid (n=15) than rifampin (n=1), adjusted OR=2.3 (95% CI: 0.3-16.1); there were two liver transplants and one death with isoniazid and none with rifampin. Overall, patients without co-morbidities had lower hepatotoxicity risk (0.1% versus 1.0%). 4R completion (53.5%) was higher than 9H (36.9%), adjusted RR=1.5 (95% CI: 1.3-1.7). Mean costs per patient were lower for rifampin than isoniazid: adjusted cost ratio=0.7 (95% CI: 0.5-0.9).Risk of severe hepatotoxicity and direct costs were lower, and completion was higher, for 4R than 9H, after adjustment for age and co-morbidities. Severe hepatotoxicity resulted in death or liver transplant in three patients receiving 9H, compared with no patients receiving 4R.

QuantiFERON-TB Gold PLUS versus QuantiFERON- TB Gold In-Tube test for diagnosing tuberculosis infection

BACKGROUND/AIMS

QuantiFERON-TB Gold PLUS (QFT-PLUS) was developed as a new version of the interferon-γ (IFN-γ) release assay that contains an extra antigen tube to elicit a CD8+ T-cell response in addition to a CD4+ T-cell response. This study aimed to evaluate the performances of QFT-PLUS versus QuantiFERON-TB Gold In-Tube (QFT-GIT) for detecting tuberculosis (TB) infection.

METHODS

Between October, 2016 and May, 2018, 137 participants were prospectively recruited and subjected to QFT-GIT and QFT-PLUS testing. The concordance between tests and performance based on different immune states and/or TB infection risk were evaluated.

RESULTS

The 137 participants were classified as follows: active TB (n = 14), TB contact (n = 14), screening before biologic therapy (n = 85) and other disease (n = 24). The positive results for either test were 100% (n = 14/14), 42.9% (n = 6/14), 15.3% (n = 13/85), and 62.5% (n = 15/24) in each four groups, respectively. The QFT-GIT and QFT-PLUS test results showed good concordance with 91.2% agreement and a Cohen's κ of 0.807. The good concordance between two tests was also observed in 64 immunocompromised subjects (agreement of 90.6% and a Cohen's κ of 0.711). The intra-class correlation coefficient for each antigen tube of the QFT-PLUS showed a good correlation with the IFN-γ release of the QFT-GIT (TB1 = 0.912, p < 0.001; TB2 = 0.918, p < 0.001).

CONCLUSION

QFT-PLUS showed highly comparable results to those of QFT-GIT for diagnosing TB infection in South Korea as well as in immunocompromised subjects.

Tools to implement the World Health Organization End TB Strategy: Addressing common challenges in high and low endemic countries

AIM

The purpose of this viewpoint is to summarize the advantages and constraints of the tools and strategies available for reducing the annual incidence of tuberculosis (TB) by implementing the World Health Organization (WHO) End TB Strategy and the linked WHO TB Elimination Framework, with special reference to Oman.

METHODS

The case-study was built based on the presentations and discussions at an international workshop on TB elimination in low incidence countries organized by the Ministry of Health, Oman, which took place from September 5 to September 7, 2019, and supported by the WHO and European Society of Clinical Microbiology and Infectious Diseases (ESCMID).

RESULTS

Existing tools were reviewed, including the screening of migrants for latent TB infection (LTBI) with interferon-gamma release assays, clinical examination for active pulmonary TB (APTB) including chest X-rays, organization of laboratory services, and the existing centres for mandatory health examination of pre-arrival or arriving migrants, including examination for APTB. The need for public-private partnerships to handle the burden of screening arriving migrants for active TB was discussed at length and different models for financing were reviewed.

CONCLUSIONS

In a country with a high proportion of migrants from high endemic countries, screening for LTBI is of high priority. Molecular typing and the development of public-private partnerships are needed.

New perspectives on difficult-to-treat tuberculosis based on old therapeutic approaches

Tuberculosis (TB) is an important clinical and public health issue worldwide. Despite improved treatment success rates following the introduction of antibiotics in daily clinical practice, the expected decline in incidence has been hampered by HIV epidemics and multi- and extensively drug-resistant TB. During the pre-antibiotic era, TB therapies were mainly based on improving hygiene conditions, strengthening the immune system, and targeting the rest of the affected lungs with invasive techniques. Detailed knowledge of old non-pharmacological therapies might support physicians and researchers in the identification of new solutions for difficult-to-treat patients. We performed a narrative literature review on the main old therapeutic options prescribed for patients with TB. The main recommendations and contraindications of sanatorium therapies (i.e., bed rest, fresh air, sunlight) and pulmonary collapse techniques are reviewed, evaluating their physiological basis and their impact on patient outcomes. We report studies describing new interventional pulmonary and surgical techniques and assess new perspectives based on old medical and surgical treatments, whose potential implementation could help complicated patients.

The impact on incident tuberculosis by kidney function impairment status: analysis of severity relationship

Background

The risk of tuberculosis (TB) in patients with impaired kidney function remains unclear by different stages of renal function impairment.

Methods

We retrospectively recruited all patients with kidney function in a tertiary-care referral center from January 2008 to December 2013 and followed them till December 2016. We defined the primary outcome as active TB development and analyzed the impact of kidney function impairment.

Results

During the study period, a total of 289,579 patients were enrolled for analysis, and of them, 1012 patients had active TB events in an average of 4.13 years of follow-up. According to kidney function impairment, the incidence rate of TB was similar in patients with no chronic kidney disease (CKD) or stage 1 and stage 2, and it increased apparently at stage 3a (167.68 per 100,000 person-years) to stage 3b, stage 4 and stage 5 (229.25, 304.95 and 349.29 per 100,000 person-years, respectively). In a Cox proportional hazard regression model, the dose response of TB risk among different stages of kidney function impairment increased significantly from CKD stage 3a to stage 5. Patients with long-term dialysis had a hazard ratio of 2.041 (1.092–3.815, p = 0.0254), which is similar to that of stage 4 CKD but lower than that of stage 5.

Conclusion

In patients with impaired kidney function, the risk of TB increases from CKD stage 3, and in stage 5, the risk is even higher than that of those receiving dialysis. Further strategies of TB control need to consider this high-risk group.

Demanding an end to tuberculosis: treatment of tuberculosis infection among persons living with and without HIV

PURPOSE OF REVIEW

More than two billion people are infected with Mycobacterium tuberculosis and few of them are ever offered therapy in spite of such treatment being associated with reduced rates of morbidity and mortality. This article reviews the current recommendations on the diagnosis and treatment of TB infection (or what is commonly referred to as 'prophylaxis' or 'preventive therapy' of latent TB) and discusses barriers to implementation that have led to low demand for this life-saving therapeutic intervention.

RECENT FINDINGS

Treatment of infection for both TB and drug-resistant TB is well tolerated and effective, and several new, shorter regimens - including rfiapenitine-based regimens of 1 month and 12 weeks duration - have been shown to be effective. Not all persons infected with TB go on to develop disease and the risk is the highest in the first 2 years after infection. Given this, additional work is needed to better identify those at the highest risk of developing active TB.

SUMMARY

Practitioners should offer newer, shorter regimens to persons who are infected with TB and at high risk of developing disease, including people living with HIV and household contacts of people living with TB who are age 5 years and under. This includes individuals who have been exposed to drug-resistant forms of disease. Socioeconomic risk factors may play a key role in the development of TB disease and should also be addressed.

Can Interferon-γ Release Assays Be Useful for Monitoring the Response to Anti-tuberculosis Treatment?: A Systematic Review and Meta-analysis

The number of studies which evaluated interferon-gamma release assays (IGRAs) results after anti-tuberculosis (TB) treatment has been rapidly increasing. The aim of this study was to investigate the potential use of IGRAs (QFT-GIT, T-SPOT.TB, QFT-Plus) in assessing the response to anti-TB treatment. We searched all studies in English language published from 1 October 2011 to 18 November 2018 in PubMed, Web of Science, and Scopus. Our search included the term "tuberculosis treatment AND interferon-γ release assay". We included studies evaluating the performance of commercial IGRAs (including QFT-GIT, T-SPOT.TB and QFT-Plus) before and after the anti-TB treatment. We performed subgroup analysis based on the age (children, adults), type of TB (active, latent, active and latent, and contacts exposed to MDR defined as MDR LTBI), type of IGRAs (QFT-GIT and T-SPOT.TB), and follow-up interval (2, 3, 4, 6, 9 months). Of the 18 included studies, 12 used QFT-GIT for assessment of IGRA performance after therapy, 1 used T-SPOT.TB, and 3 used both QFT-GIT and T-SPOT.TB. Since then, only two studies have assessed the QFT-Plus performance during therapy. According to the results of the meta-analysis, the pooled rate of positive IGRAs (QFT-GIT and T-SPOT.TB) following anti-TB therapy was estimated at 76% [95% CI 70-81%] and no difference was found compared to the pooled positive rate of IGRAs before initiation of therapy which was 76% [95% CI 60-89%]. The subgroup analysis showed that the pooled rate of positive IGRAs (QFT-GIT and T-SPOT.TB) after anti-TB therapy was significantly higher in monitoring active TB subjects [80% (95% CI 74-88%)] than LTBI [71% (95% CI 70-81%)]. Available data are now sufficient to suggest that monitoring changes in the IGRAs (QFT-GIT and T-SPOT.TB) response during anti-TB treatment may have limited use in evaluating the effectiveness of treatment, while the monitoring changes in QFT-Plus during anti-tubercular treatment are recommended to determine treatment efficacy or for treatment monitoring. Further research is needed to establish the efficacy of this new assay as marker on a larger scale for treatment monitoring.

Incidence of latent tuberculosis infection among health science students during clinical training

BACKGROUND:

The prevalence of latent tuberculosis infection (LTBI) has been found to be high among students undergoing clinical training. The aim of this study is to determine the incidence of LTBI among undergraduate health science students after their clinical training and to compare the risk between different college specialties.

METHODS:

This is a retrospective cohort study of students who completed their clinical training from 2010 to 2017. The risk of LTBI was defined based on the conversion of tuberculin skin test (TST) results from negative at the start of training to positive after the completion of training.

RESULTS:

A total of 2000 students were evaluated, of whom 1997 were included in this analysis. Six percent tested positive in the first TST of the initial screening. Ten percent of students with a normal baseline TST converted to positive on the follow-up TST. Clinical training in the college of medicine increased the risk of LTBI by 76% (odds ratio: 1.76; 95% confidence interval: 1.04– 2.96; P = 0.03) compared to clinical training in other medical colleges.

CONCLUSIONS:

The risk of acquiring LTBI during clinical training in health science colleges is 10%. Students in the college of medicine are at significantly higher risk of LTBI than students of other health science specialties.

Tuberculosis recurrences and predictive factors in a vulnerable population in Catalonia

BACKGROUND

Patients with a history of tuberculosis (TB) have a high probability of recurrence because long-term cure is not always maintained in successfully treated patients. The aim of this study was to identify the probability of TB recurrence and its predictive factors in a cohort of socially vulnerable patients who completed treatment in the TB referral center in Catalonia, which acts as the center for patients with social and health problems.

METHODS

This retrospective open cohort study included all patients diagnosed with TB who were admitted and successfully treated in Serveis Clínics between 2000 and 2016 and who remained disease-free for a minimum of 1 year after treatment completion. We calculated the incidence density of TB recurrences per person-years of follow-up. We also estimated the cumulative incidence of TB recurrence at 1, 2, 5, and 10 years of follow-up. Bivariate analysis was conducted using Kaplan-Meier curves. Multivariate analysis was conducted using Cox regression. Hazard ratios (HR) were calculated with their 95% confidence intervals (95%CI).

RESULTS

There were 839 patients and 24 recurrences (2.9%), representing 0.49 per 100 person-years. The probability of a recurrence was 0.63% at 1 year of follow-up, 1.35% at 2 years, and 3.69% at 5 years. The multivariate analysis showed that the predictive factors of recurrence were age older than 34 years (aHR = 3.90; CI = 1.06-14.34 at age 35-45 years and aHR = 3.88; CI = 1.02-14.80 at age >45 years) and resistance to at least one anti-TB drug (aHR = 2.91; CI = 1.11-7.65).

CONCLUSIONS

Attention should be paid to socially vulnerable persons older than 34 years with a previous episode of resistant TB. Surveillance resources should be directed toward adequately treated patients who nevertheless have a high risk of recurrence.

Cost-effectiveness of 3 months of weekly rifapentine and isoniazid compared with other standard treatment regimens for latent tuberculosis infection: a decision analysis study

Background

Latent tuberculosis infection (LTBI) is a critical driver of the global burden of active TB, and therefore LTBI treatment is key for TB elimination. Treatment regimens for LTBI include self-administered daily isoniazid for 6 (6H) or 9 (9H) months, self-administered daily rifampicin plus isoniazid for 3 months (3RH), self-administered daily rifampicin for 4 months (4R) and weekly rifapentine plus isoniazid for 3 months self-administered (3HP-SAT) or administered by a healthcare worker as directly observed therapy (3HP-DOT). Data on the relative cost-effectiveness of these regimens are needed to assist policymakers and clinicians in selecting an LTBI regimen.

Objectives

To evaluate the cost-effectiveness of all regimens for treating LTBI.

Methods

We developed a Markov model to investigate the cost-effectiveness of 3HP-DOT, 3HP-SAT, 4R, 3RH, 9H and 6H for LTBI treatment in a cohort of 10000 adults with LTBI. Cost-effectiveness was evaluated from a health system perspective over a 20 year time horizon.

Results

Compared with no preventive treatment, 3HP-DOT, 3HP-SAT, 4R, 3RH, 9H and 6H prevented 496, 470, 442, 418, 370 and 276 additional cases of active TB per 10000 patients, respectively. All regimens reduced costs and increased QALYs compared with no preventive treatment. 3HP was more cost-effective under DOT than under SAT at a cost of US$27948 per QALY gained.

Conclusions

Three months of weekly rifapentine plus isoniazid is more cost-effective than other regimens. Greater recognition of the benefits of short-course regimens can contribute to the scale-up of prevention and achieving the 'End TB' targets.

Identifying gaps in the quality of latent tuberculosis infection care

Latent tuberculosis infection (LTBI) occurs after transmission and acquisition of infection, when the tuberculosis (TB) bacteria lie dormant in a person. Nearly one-quarter of the world's population is estimated to have LTBI, yet few studies have been published assessing the quality of LTBI services globally. This paper reviews issues to providing patient-centered LTBI services and offers an example framework to formally assess the quality of LTBI patient care. By applying the LTBI cascade of care model, TB programmes can evaluate the gaps and barriers to high-quality care and develop locally-driven solutions to improve LTBI services. Quality care for LTBI must address some of the key challenges to services including: (1) low prioritization of LTBI; (2) gaps in healthcare provider knowledge about testing and treatment; and (3) patient concerns about side effects of preventive treatment regimens. TB programmes need to ensure that these issues are addressed in a patient-centered manner, with clear communication and ongoing evaluation of the quality of LTBI services. Quality LTBI care must be a central focus, particularly identifying and engaging more household contacts in preventive treatment, in order to halt the progression to active disease thereby stopping TB transmission globally.

Diagnosing Tuberculosis Using Deep Convolutional Neural Network

One of the global topmost causes of death is Tuberculosis (TB) which is caused by mycobacterium bacillus. The increase rate of infected people and the recorded deaths from TB disease is as a result of its transmissibility, lack of early diagnosis, and inadequate professional radiologist in developing regions where TB is more prevalent. Tuberculosis is unquestionably curable but needs to be detected early for necessary treatment to be effective. Many screening techniques are available, but chest radiograph has proven to be valuable for screening pulmonary diseases but hugely dependent on the interpretational skill of an expert radiologist. We propose a Computer-Aided Detection model using Deep Convolutional Neural Networks to automatically detect TB from Montgomery County (MC) Tuberculosis radiographs. Our proposed model performed at 87.1% validation accuracy and evaluated using confusion matrix and accuracy as metrics.

PURL: A better approach to preventing active TB?

Nine months of isoniazid prevents active TB in those with latent disease. But is there a shorter, less toxic option?

Tuberculosis Transmission in a Primary School and a Private Language School. An Estimation of Infectivity

Introduction: Belgium is a country with low incidence of tuberculosis (TB) and a very low number of TB cases in children. Children in contact with an adult smear-positive TB case are at high risk of transmission. Early diagnosis is important as young children have a significant predisposition of developing TB disease. In this paper, we describe two outbreaks after exposure to, respectively, two teachers with smear-positive pulmonary TB: one in a primary school, a nursery teacher, and another in a private language school. Methods: An exposure investigation was carried out in both index cases household and school, according to the stone-in-the-pond principle. The tuberculin skin test (TST) was used a screening tool. The time elapsed between TB diagnosis in the index case and contact investigation was, respectively, 1 and 3 weeks. If this initial test was negative, it was repeated after a "window period" of ≥8 weeks. Results: Index cases showed a transmission rate of, respectively, 13 and 40% in their classes at school, defined as casual contacts. The proximity of contact increased the risk of infection. TB disease was observed in, respectively, 4 and 11% of all the casual contacts; all of them were children younger than 5 years old. TB-infected and children with active TB disease had good compliance with recommended treatment. Uptake of chemoprophylaxis during the "window period" was poor, respectively, only 32-42%, in children under 5 years with an initially negative TST. Discussion: The World Health Organization recommends to screen all young children (<5 years old) who have close contact with a person affected by pulmonary TB and to initiate Latent tuberculosis infection treatment even before infection can be demonstrated, after ruling out active TB disease. Despite this knowledge, a small percentage of the children younger than 5 years with no proof of infection was treated with the proposed chemoprophylactic treatment, in both cases. Conclusion: This exposure investigation of two teachers detects high transmission among family contacts and school casual contacts. Recommendations for chemoprophylactic treatment in children <5 years showed low compliance, reflecting the difficulty of communication to staff, parents, and children in a school outbreak. It is essential to develop a new approach for this vulnerable group of patients. This approach could be improved, applied, and evaluated by National TB Control Programs, involving public and private health services. Public health authorities play a role in raising public awareness about the risks of TB for young children.

Latent tuberculosis infection screening in persons newly-diagnosed with HIV infection in Italy: A multicentre study promoted by the Italian Society of Infectious and Tropical Diseases

BACKGROUND

The Italian Society of Infectious and Tropical Diseases performed a survey on the application of guidelines for the management of persons living with HIV (PLWH), to evaluate current practice and the yield of screening for latent tuberculosis infection (LTBI) in newly-diagnosed PLWH; in addition, the offer of preventive therapy to LTBI individuals and the completion rate were analysed.

MATERIALS AND METHODS

Newly-diagnosed PLWH in nine centres were evaluated retrospectively (2016/2017) using binary and multinomial logistic regression to identify factors associated with LTBI diagnostic screening and QuantiFERON (QFT) results.

RESULTS

Of 801 patients evaluated, 774 were studied after excluding active TB. LTBI tests were performed in 65.5%. Prescription of an LTBI test was associated with being foreign-born (odds ratio (OR) 3.19, p < 0.001), older (for 10-year increments, OR 1.22, p = 0.034), and having a CD4 count <100 cells/mm³ vs ≥500 cells/mm³ (OR 2.30, p = 0.044). LTBI was diagnosed in 6.5% of 495 patients evaluated by QFT. Positive results were associated with being foreign-born (relative risk ratio (RRR) 30.82, p < 0.001), older (for 10-year increments, RRR 1.78, p = 0.003), and having a high CD4 count (for 100 cells/mm³ increments, RRR 1.26, p < 0.003). Sixteen LTBI individuals started TB preventive therapy and eight completed it.

CONCLUSIONS

LTBI screening is inconsistently performed in newly-diagnosed PLWH. Furthermore, TB preventive therapy is not offered to all LTBI individuals and compliance is poor.