Cost-effectiveness of tuberculosis evaluation and treatment of newly-arrived immigrants

Tuberculosis in United States-Bound Follow-to-Join Asylees, 2014-2019

Persons may seek asylum in the United States or at a U.S. port of entry. Principal asylees are those who are granted asylum status. Their spouse and unmarried children under 21 years of age may be granted asylum if accompanying, or following to join, the principal asylees. U.S.-bound follow-to-join asylees must undergo an overseas medical examination that includes tuberculosis (TB) screening. Culture-based overseas TB screening in U.S.-bound follow-to-join asylees has not been evaluated. We evaluated data from overseas TB screening in 19,088 arrivals of follow-to-join asylees during 2014-2019 and assessed data from their postarrival evaluation, which is recommended for those at risk for TB. Of 19,088 arrivals of follow-to-join asylees, 29 (152 cases/100,000 persons) met criteria for class B0 TB (recent completion of TB treatment overseas) and 340 (1,781 cases/100,000 persons) met criteria for class B1 pulmonary TB (chest radiograph/clinical symptoms suggestive of TB but negative sputum cultures overseas). Of 6,847 persons aged 2 to 14 years from countries with a WHO-estimated TB incidence of ≥20 cases/100,000 population/year, 408 (6.0%) were classified as class B2 latent TB infection (LTBI). Postarrival evaluations were completed in 44.8%, 51.5%, and 40.4% of persons with class B0 TB, class B1 TB, and class B2 LTBI, respectively. In conclusion, culture-based overseas TB screening in U.S.-bound follow-to-join asylees is effective in identifying those with TB (class B0 TB) or those at risk for TB (class B1 TB and class B2 LTBI). Completion of postarrival evaluation for newly arrived follow-to-join asylees was less frequent than that reported for immigrants and refugees.

Cost-Effectiveness Analysis of Vedolizumab Compared With Infliximab in Anti-TNF-α-Naïve Patients With Moderate-to-Severe Ulcerative Colitis in China

Objective: To evaluate the cost effectiveness of vedolizumab vs. infliximab in the treatment of anti-tumor necrosis factor-alpha (TNF-α)-naïve patients with moderate-to-severe active ulcerative colitis (UC) in China. Methods: The costs and effectiveness of vedolizumab and infliximab in the treatment of anti-TNF-α naïve patients with moderate-to-severe active UC were compared using a hybrid decision tree model and a Markov model. From the perspective of the Chinese healthcare system, this study simulated the lifetime health benefits [quality-adjusted life-years (QALYs)] and costs (USD) for patients with UC from the induction phase to the maintenance phase, with an annual discount rate of 5%. The clinical efficacy and transition probability data were based on a previously published network meta-analysis. The health utility, surgical risk, biologic drug discontinuation rate, and mortality were derived from previous literature and the Chinese statistical yearbook. The cost data were based on China's drug purchase and biding platform and the results of a survey sent to clinicians in 18 tertiary hospitals. One-way and probabilistic sensitivity analyses (PSAs) were performed to validate the robustness of the models' assumptions and specific parameter estimates. Results: The results of the base-case analyses showed that compared with infliximab, vedolizumab led to a gain of 0.25 QALYs (9.56 vs. 9.31 QALYs) and was less expensive by $7,349 ($180,138 vs. 187,487), indicating that the use of vedolizumab was a dominant strategy. The results of one-way sensitivity analyses suggested that the annual discount rate and health-state costs had the greatest impact, but the results were otherwise consistent with those of the base-case analyses. The PSAs suggested that vedolizumab had a 98.6% probability of being effective at a threshold of 3 times the gross domestic product (GDP) per capita in China in 2020. Conclusion: Compared with infliximab, vedolizumab appears to be a more cost-effective option in the treatment of anti-TNF-α naïve adult patients with moderate-to-severe, active UC in China.

Cost-Effectiveness of Vedolizumab in the Treatment of Moderate-to-Severe Crohn's Disease in China

INTRODUCTION

To compare the cost-effectiveness of vedolizumab with that of conventional therapy in patients with moderate-to-severe active Crohn's disease (CD) in China.

METHODS

A decision tree and Markov model were built to predict the lifetime cost and health outcomes in the induction phase and maintenance phase of vedolizumab treatment and conventional therapy (a combination of corticosteroids, immunosuppressants, and aminosalicylates) in adult patients with moderate-to-severe active CD from the perspective of China's healthcare system. Clinical efficacy and health utility were derived from the GEMINI 2 and GEMINI 3 trials and published literature. Costs were mainly obtained from clinical physician surveys in China and are presented in 2020 US dollars. Health outcomes (quality-adjusted life years, QALYs) and costs were discounted at an annual rate of 5%. The incremental cost per QALY gained was used to compare the cost-effectiveness of the two treatments. One-way and probabilistic sensitivity analyses (PSAs) were performed to test the robustness of the model.

RESULTS

The model predicted more QALYs (9.92 vs 9.00 QALYs) and lower incurred costs ($288,284 vs $309,680) in vedolizumab than in conventional therapy in a mixed population (anti-TNF-naïve and anti-TNF-failure populations) over a lifetime horizon in the base-case analysis. Similar results were observed in the anti-TNF-naïve and anti-TNF-failure subgroups of patients with CD. One-way sensitivity analysis results suggested that health state cost was the most influential factor in the model. The PSA results supported the dominance of vedolizumab in the base-case analysis.

CONCLUSION

Vedolizumab appears to be a cost-effective strategy option in the treatment of adult patients with moderate-to-severe active CD in China in both anti-TNF-naïve and anti-TNF-failure populations.

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.

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.

The effectiveness and cost-effectiveness of screening for latent tuberculosis among migrants in the EU/EEA: a systematic review

Migrants account for a large and growing proportion of tuberculosis (TB) cases in low-incidence countries in the European Union/European Economic Area (EU/EEA) which are primarily due to reactivation of latent TB infection (LTBI). Addressing LTBI among migrants will be critical to achieve TB elimination. Methods: We conducted a systematic review to determine effectiveness (performance of diagnostic tests, efficacy of treatment, uptake and completion of screening and treatment) and a second systematic review on cost-effectiveness of LTBI screening programmes for migrants living in the EU/EEA. Results: We identified seven systematic reviews and 16 individual studies that addressed our aims. Tuberculin skin tests and interferon gamma release assays had high sensitivity (79%) but when positive, both tests poorly predicted the development of active TB (incidence rate ratio: 2.07 and 2.40, respectively). Different LTBI treatment regimens had low to moderate efficacy but were equivalent in preventing active TB. Rifampicin-based regimens may be preferred because of lower hepatotoxicity (risk ratio = 0.15) and higher completion rates (82% vs 69%) compared with isoniazid. Only 14.3% of migrants eligible for screening completed treatment because of losses along all steps of the LTBI care cascade. Limited economic analyses suggest that the most cost-effective approach may be targeting young migrants from high TB incidence countries. Discussion: The effectiveness of LTBI programmes is limited by the large pool of migrants with LTBI, poorly predictive tests, long treatments and a weak care cascade. Targeted LTBI programmes that ensure high screening uptake and treatment completion will have greatest individual and public health benefit.

Cost-effectiveness of ustekinumab in moderate to severe Crohn's disease in Sweden

BACKGROUND

Human monoclonal antibody ustekinumab is a novel Crohn's disease (CD) treatment blocking pro-inflammatory cytokines interleukin-12 and 23. The study's objective was to assess cost-effectiveness of ustekinumab in moderate to severely active CD in Sweden.

METHODS

A cost-effectiveness model with an induction phase decision-tree structure and a maintenance phase Markov cohort structure was constructed. CD was represented by five health-states: remission, mild, moderate-severe, surgery and death. Ustekinumab was compared to adalimumab in patients who had failed conventional care, some of which had tried TNF-alpha-inhibitor(s) without experiencing treatment failure or side effects ("conventional care failure population") and to vedolizumab in patients previously failing TNF-alpha-inhibitor treatment. Discontinuation probabilities, utilities and ustekinumab induction efficacy were sourced from phase-III trials. Maintenance and comparator efficacy came from network-meta and treatment-sequence analyses. Resource use and unit costs were derived from literature and validated by clinical experts. The analysis had a societal perspective, a life-time time-horizon, and 2-year treatment duration. The results robustness was tested in univariate and probabilistic sensitivity analyses. Cost-effectiveness was estimated using quality-adjusted life-years (QALYs).

RESULTS

Ustekinumab dominated adalimumab in conventional care failure population (costs: - €6984, QALYs: + 0.232). In TNF-alpha-inhibitor failure population ustekinumab accrued 0.133 more QALYs than vedolizumab, yielding a €30,282 incremental cost-effectiveness ratio. Results were sensitive to decreasing the time horizon and increased treatment duration. At Swedish reference willingness-to-pay of €63,000 (SEK 600,000), ustekinumab had 94% probability of being cost-effective versus adalimumab, and 72% versus vedolizumab.

CONCLUSIONS

Results indicate ustekinumab dominates adalimumab in conventional care failure population, and is cost-effective versus vedolizumab in TNF-alpha-inhibitor failure population.

Disparities in model-based cost-effectiveness analyses of tuberculosis diagnosis: A systematic review

Background

Structural approach disparities were minimally addressed in past systematic reviews of model-based cost-effectiveness analyses addressing Tuberculosis management strategies. This review aimed to identify the structural approach disparities in model-based cost-effectiveness analysis studies addressing Tuberculosis diagnosis and describe potential hazards caused by those disparities.

Methods

A systematic search to identify studies published before October 2015 was performed in five electronic databases. After removal of duplication, studies’ titles and abstracts were screened based on predetermined criteria. The full texts of potentially relevant studies were subsequently screened and excluded when they did not address active pulmonary Tuberculosis diagnosis. Quality of the studies was assessed using the “Philips’ checklist.” Various data regarding general information, cost-effectiveness results, and disease modeling were extracted using standardized data extraction forms. Data pertaining to models’ structural approaches were compared and analyzed qualitatively for their applicability in various study settings, as well as their potential influence on main outcomes and cost-effectiveness conclusion.

Results

A total of 27 studies were included in the review. Most studies utilized a static model, which could underestimate the cost-effectiveness of the diagnostic tools strategies, due to the omission of indirect diagnosis effects, i.e. transmission reduction. A few structural assumption disparities were found in the dynamic models. Extensive disparities were found in the static models, consisting of varying structural assumptions regarding treatment outcomes, clinical diagnosis and empirical treatment, inpatient discharge decision, and re-diagnosis of false negative patients.

Conclusion

In cost-effectiveness analysis studies addressing active pulmonary Tuberculosis diagnosis, models showed numerous disparities in their structural approaches. Several structural approaches could be inapplicable in certain settings. Furthermore, they could contribute to under- or overestimation of the cost-effectiveness of the diagnosis tools or strategies. They could thus lead to ambiguities and difficulties when interpreting a study result. A set of recommendations is proposed to manage issues related to these structural disparities.

Economic analysis of CDC's culture- and smear-based tuberculosis instructions for Filipino immigrants

SETTING

In 2007, the US Centers for Disease Control and Prevention (CDC) revised its tuberculosis (TB) technical instructions for panel physicians who administer mandatory medical examinations among US-bound immigrants. Many US-bound immigrants come from the Philippines, a high TB prevalence country.

OBJECTIVE

To quantify economic and health impacts of smear- vs. culture-based TB screening.

DESIGN

Decision tree modeling was used to compare three Filipino screening programs: 1) no screening, 2) smear-based screening, and 3) culture-based screening. The model incorporated pre-departure TB screening results from Filipino panel physicians and CDC databases with post-arrival follow-up outcomes. Costs (2013 $US) were examined from societal, immigrant, US Public Health Department and hospitalization perspectives.

RESULTS

With no screening, an annual cohort of 35 722 Filipino immigrants would include an estimated 450 TB patients with 264 hospitalizations, at a societal cost of US$9.90 million. Culture-based vs. smear-based screening would result in fewer imported cases (80.9 vs. 310.5), hospitalizations (19.7 vs. 68.1), and treatment costs (US$1.57 million vs. US$4.28 million). Societal screening costs, including US follow-up, were greater for culture-based screening (US$5.98 million) than for smear-based screening (US$3.38 million). Culture-based screening requirements increased immigrant costs by 61% (US$1.7 million), but reduced costs for the US Public Health Department (22%, US$750 000) and of hospitalization (70%, US$1 020 000).

CONCLUSION

Culture-based screening reduced imported TB and US costs among Filipino immigrants.

Cost-effectiveness of vedolizumab compared with infliximab, adalimumab, and golimumab in patients with ulcerative colitis in the United Kingdom

OBJECTIVE

To examine the clinical and economic impact of vedolizumab compared with infliximab, adalimumab, and golimumab in the treatment of moderately to severely active ulcerative colitis (UC) in the United Kingdom (UK).

METHODS

A decision analytic model in Microsoft Excel was used to compare vedolizumab with other biologic treatments (infliximab, adalimumab, and golimumab) for the treatment of biologic-naïve patients with UC in the UK. Efficacy data were obtained from a network meta-analysis using placebo as the common comparator. Other inputs (e.g., unit costs, adverse-event disutilities, probability of surgery, mortality) were obtained from published literature. Costs were presented in 2012/2013 British pounds. Outcomes included quality-adjusted life-years (QALYs). Costs and outcomes were discounted by 3.5% per year. Incremental cost-effectiveness ratios were presented for vedolizumab compared with other biologics. Univariate and multivariate probabilistic sensitivity analyses were conducted to assess model robustness to parameter uncertainty.

RESULTS

The model predicted that anti-tumour necrosis factor-naïve patients on vedolizumab would accrue more QALY than patients on other biologics. The incremental results suggest that vedolizumab is a cost-effective treatment compared with adalimumab (incremental cost-effectiveness ratio of £22,735/QALY) and dominant compared with infliximab and golimumab. Sensitivity analyses suggest that results are most sensitive to treatment response and transition probabilities. However, vedolizumab is cost-effective irrespective of variation in any of the input parameters.

CONCLUSIONS

Our model predicted that treatment with vedolizumab improves QALY, increases time in remission and response, and is a cost-effective treatment option compared with all other biologics for biologic-naïve patients with moderately to severely active UC.

Cost-effectiveness of vedolizumab compared with conventional therapy for ulcerative colitis patients in the UK

Objective

To examine the clinical and economic impact of vedolizumab compared with conventional therapy in the treatment of moderately-to-severely active ulcerative colitis (UC) in the UK based on results of the GEMINI I trial.

Methods

A decision-analytic model in Microsoft Excel was used to compare vedolizumab with conventional therapy (aminosalicylates, corticosteroids, immunomodulators) for the treatment of patients with UC in the UK. We considered the following three populations: the overall intent-to-treat population from the GEMINI I trial, patients naïve to anti-TNF therapy, and those who had failed anti-TNF-therapy. Population characteristics and efficacy data were obtained from the GEMINI I trial. Other inputs (eg, unit costs, probability of surgery, mortality) were obtained from published literature. Time horizon was a lifetime horizon, with costs and outcomes discounted by 3.5% per year. One-way and probabilistic sensitivity analyses were conducted to measure the impact of parameter uncertainty.

Results

Vedolizumab had incremental cost-effectiveness ratios of £4,095/quality-adjusted life-year (QALY), £4,423/QALY, and £5,972/QALY compared with conventional therapy in the intent-to-treat, anti-TNF-naïve, and anti-TNF-failure populations, respectively. Patients on vedolizumab accrued more QALYs while incurring more costs than patients on conventional therapy. The sensitivity analyses showed that the results were most sensitive to induction response and transition probabilities for each treatment.

Conclusion

The results suggest that vedolizumab results in more QALYs and may be a cost-effective treatment option compared with conventional therapy for both anti-TNF-naïve and anti-TNF-failure patients with moderately-to-severely active UC.

Factors That Influence Treatment Completion for Latent Tuberculosis Infection

INTRODUCTION

The aim of this study is to describe factors associated with noncompletion of latent tuberculosis infection (LTBI) therapy.

METHODS

We conducted a retrospective cohort study of adults who initiated LTBI treatment with isoniazid, rifampin, or isoniazid-rifapentine at 5 clinics. Demographic, treatment, and monitoring characteristics were abstracted. We estimated descriptive statistics and compared differences between completers and noncompleters using t tests and χ2 tests.

RESULTS

The rate of completion across LTBI regimens was 66% (n = 393). A greater proportion of noncompleters were unmarried, used tobacco and/or alcohol, and had more medical problems than completers (all P < .05). A larger proportion of noncompleters received charity care compared with completers (P < .001). The most common reason for treatment discontinuation was loss to follow-up; the majority of these participants were treated with the longest isoniazid-only regimen.

CONCLUSIONS

Patients at risk of progression to active tuberculosis with factors associated with noncompletion may benefit from interventions that enhance adherence to LTBI therapy. These interventions could include enhanced outreach, incentive programs, or home visits.

Treatment completion for latent tuberculosis infection: a retrospective cohort study comparing 9 months of isoniazid, 4 months of rifampin and 3 months of isoniazid and rifapentine

BACKGROUND

The U.S. Centers for Disease Control and Prevention (CDC) recommended a new regimen for treatment of latent tuberculosis (three months of weekly isoniazid and rifapentine) in late 2011. While completion rates of this regimen were reported to be higher than nine months of isoniazid, little is known about the completion rates of three months of isoniazid and rifapentine compared to nine months of isoniazid or four months of rifampin in actual use scenarios.

METHODS

We conducted a retrospective cohort study comparing treatment completion for latent tuberculosis (TB) infection in patients treated with nine months of isoniazid, three months of isoniazid and rifapentine or four months of rifampin in outpatient clinics and a public health TB clinic in Seattle, Washington. The primary outcome of treatment completion was defined as 270 doses of isoniazid within 12 months, 120 doses of rifampin within six months and 12 doses of isoniazid and rifapentine within four months.

RESULTS

Three hundred ninety-three patients were included in the study. Patients were equally likely to complete three months of weekly isoniazid and rifapentine or four months of rifampin (85% completion rate of both regimens), as compared to 52% in the nine months of isoniazid group (p < 0.001). These associations remained statistically significant even after adjusting for clinic location and type of monitoring. Monitoring type (weekly versus monthly versus less often than monthly) had less impact on treatment completion than the type of treatment offered.

CONCLUSIONS

Patients were equally as likely to complete the three months of isoniazid and rifapentine as four months of rifampin. Four months of rifampin is similar in efficacy compared to placebo as isoniazid and rifapentine but does not require directly observed therapy (DOT), and is less expensive compared to combination therapy with isoniazid and rifapentine, and thus can be the optimal treatment regimen to achieve the maximal efficacy in a community setting.

Getting to Zero: Tuberculosis Elimination in California

This review of tuberculosis epidemiology is intended to provide a historical perspective on the public health approach to tuberculosis (TB) control in California. This historical context offers a lens through which to view current epidemiologic trends and insight into how new therapeutic tools can be applied. Since 1993, the year detailed case reporting was instituted, California has had a decrease in recent TB transmission as evidenced by a reduction in pediatric cases and an increased percentage of cases attributable to progression of latent infection to TB disease in the foreign-born population. Overall, there has been a dramatic decline in the annual TB case count, but the speed of the decline has slowed over the last several years. At the current pace and case count of 2137 in 2015, California will not achieve TB elimination (<1 TB case per one million population) for at least 100 years. There are an estimated 2.1 million persons in California with latent TB infection. Modeling suggests that LTBI detection and treatment are important in reaching TB elimination. For this reason, a coalition of stakeholders in California is exploring novel approaches to accelerate the case decline in order to prevent unnecessary disease and death.

The impact of migration on tuberculosis epidemiology and control in high-income countries: a review

Tuberculosis (TB) causes significant morbidity and mortality in high-income countries with foreign-born individuals bearing a disproportionate burden of the overall TB case burden in these countries. In this review of tuberculosis and migration we discuss the impact of migration on the epidemiology of TB in low burden countries, describe the various screening strategies to address this issue, review the yield and cost-effectiveness of these programs and describe the gaps in knowledge as well as possible future solutions.The reasons for the TB burden in the migrant population are likely to be the reactivation of remotely-acquired latent tuberculosis infection (LTBI) following migration from low/intermediate-income high TB burden settings to high-income, low TB burden countries.TB control in high-income countries has historically focused on the early identification and treatment of active TB with accompanying contact-tracing. In the face of the TB case-load in migrant populations, however, there is ongoing discussion about how best to identify TB in migrant populations. In general, countries have generally focused on two methods: identification of active TB (either at/post-arrival or increasingly pre-arrival in countries of origin) and secondly, conditionally supported by WHO guidance, through identifying LTBI in migrants from high TB burden countries. Although health-economic analyses have shown that TB control in high income settings would benefit from providing targeted LTBI screening and treatment to certain migrants from high TB burden countries, implementation issues and barriers such as sub-optimal treatment completion will need to be addressed to ensure program efficacy.

High Discordance Between Pre-US and Post-US Entry Tuberculosis Test Results Among Immigrant Children: Is it Time to Adopt Interferon Gamma Release Assay for Preentry Tuberculosis Screening?

BACKGROUND

Since 2007, immigration applicants 2-14 years old with a tuberculin skin test (TST) ≥10 mm and an otherwise negative evaluation for tuberculosis (TB) are assigned a classification for TB infection and instructed to seek domestic evaluation upon arrival in the US in accordance with Centers for Disease Control and Prevention instructions. We examined the characteristics and outcome of domestic evaluation of immigrant children who arrived in California with a positive TST on preimmigration examination to inform the preimmigration TB screening process.

METHODS

Retrospective analysis of the characteristics and results of domestic evaluation of immigrants 2-14 years old who arrived in California with a classification for TB infection during October 1, 2008-September 30, 2013 was performed. TB disease was determined by matching preimmigration records with the California TB registry.

RESULTS

Among a total of 12,544 immigrant children included, 7786 (62%) were evaluated for TB postentry. Of these, 5243 (67%) were tested with TST or interferon gamma release assay (IGRA), and 2371 (45%) had a positive test. Of those tested with IGRA (n = 4035), 914 (23%) were positive. The proportion with positive IGRA increased significantly with age (years): 2-4 (11%), 5-9 (19%), 10-14 (28%), P < 0.0001; was lowest among arrivers from China (6%) and highest among arrivers from Mexico (48%). Nine children (0.07%) had TB disease within 5 years after arrival.

CONCLUSIONS

The majority of immigrant children with a positive preimmigration TST tested negative for TB infection on domestic evaluation using TST or IGRA. Inclusion of IGRA in preimmigration TB screening is likely to reduce subsequent testing, treatment and cost of evaluations among immigrant children to the US.

Health status and quality of life in tuberculosis

Tuberculosis (TB) is a leading cause of global morbidity, yet there is limited information regarding its impact on quality of life and health status. This is surprising given the implications for patient care, the evaluation of novel treatments or preventative strategies, and also health policy. Furthermore, there is no validated TB-specific instrument that measures health status, and thus a wide and non-standardized range of assessment tools have been employed. The studies to date have chosen a number of different comparator populations, and in many TB endemic areas there is a lack of normative data regarding the health status of the general population. Systematic evaluations of quality of life are urgently needed in specific groups, including those with extrapulmonary TB, drug-resistant disease, HIV co-infection, and latent TB infection, and in children with TB; the assessment of post-treatment disability is also required.

A scoping review of cost-effectiveness of screening and treatment for latent tubercolosis infection in migrants from high-incidence countries

Background

In low-incidence countries, most tuberculosis (TB) cases occur among migrants and are caused by reactivation of latent tuberculosis infection (LTBI) acquired in the country of origin. Diagnosis and treatment of LTBI are rarely implemented to reduce the burden of TB in immigrants, partly because the cost-effectiveness profile of this intervention is uncertain.

The objective of this research is to perform a review of the literature to assess the cost-effectiveness of LTBI diagnosis and treatment strategies in migrants.

Methods

Scoping review of economic evaluations on LTBI screening strategies for migrants was carried out in Medline.

Results

Nine studies met the inclusion criteria. LTBI screening was cost-effective according to seven studies. Findings of four studies support interferon gamma release assay as the most cost-effective test for LTBI screening in migrants. Two studies found that LTBI screening is cost-effective only if carried out in immigrants who are contacts of active TB cases.

Discussion and Conclusions

Our findings support the cost-effectiveness of LTBI diagnostic and treatment strategies in migrants especially if they are focused on young subjects from high incidence countries. These strategies could represent and adjunctive and synergistic tool to achieve the ambitious aim of TB elimination.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-015-1045-3) contains supplementary material, which is available to authorized users.

Cost Resulting from Anti-Tuberculosis Drug Shortages in the United States: A Hypothetical Cohort Study

Background

From 2012 through 2014, the United States experienced acute shortages and price escalations of several first-line anti-tuberculosis (TB) medications. Because secondary TB drug regimens are longer and adverse events occur more frequently with them, we sought to conservatively estimate the cost, to patients and the health care system, of TB treatment and medication adverse events from alternative regimens during drug shortages.

Methods

We assessed the cost of treatment for TB disease in the absence of isoniazid (INH), rifampin (RIF), or pyrazinamide (PZA), or both INH and RIF. We simulated adverse events based on published probabilities using a monthly discrete-time stochastic model. For total costs, we summed costs of medications, routine testing, and treatment of adverse events using procedural terminology codes. We report average cost ratios of TB treatment during drug shortages to standard TB treatment.

Results

The cost ratio of TB treatment without INH, RIF, or PZA to standard treatment was 1.7 (Range: 1.2, 2.3), 4.9 (Range: 3.2, 7.3), and 1.1 (Range: 0.7, 1.7) times higher, respectively. Without both INH and RIF, the cost ratio was 18.6 (Range: 10.0, 39.0) times higher. When the prices for INH, RIF and PZA were increased, the cost for standard treatment increased by a factor of 2.7 (Range: 1.9, 3.0). The percentage of patients experiencing at least one adverse event while taking standard therapy was 3.9% (Range: 1.3%, 11.8%). This percentage increased to 51.5% (Range: 20.1%, 83.8%) when RIF was unavailable, and increased to 82.5% (Range: 41.2%, 98.5%) when both INH and RIF were unavailable.

Conclusions

Our conservative model illustrates that an interruption in first-line anti-TB medications leads to appreciable additional costs and adverse events for patients. The availability of these drugs in the United States should be ensured. Models that incorporate the effectiveness of alternative regimens, delays in treatment initiation, and TB transmission can provide broader perspectives on the impact of drug shortages.

Cost Effectiveness of Preventive Treatment for Tuberculosis in Special High-Risk Populations

OBJECTIVE

In view of the goal of eliminating tuberculosis (TB) by 2050, economic evaluations of interventions against the development of TB are increasingly requested. Little research has been published on the incremental cost effectiveness of preventative therapy (PT) in groups at high risk for progression from latent TB infection (LTBI) with Mycobacterium TB (MTB) to active disease. A systematic review of studies with a primary focus on model-driving inputs and methodological differences was conducted.

METHODS

A search of MEDLINE, the Cochrane Library and EMBASE to July 2014 was undertaken, and reference lists of eligible articles and relevant reviews were examined.

RESULTS

A total of 876 citations were retrieved, with a total of 24 studies being eligible for inclusion, addressing six high-risk groups other than contact persons. Results varied considerably between studies and countries, and also over time. Although the selected studies generally demonstrated cost effectiveness for PT in HIV-infected subjects and healthcare workers (HCWs), the outcome of these analyses can be questioned in light of recent epidemiologic data. For immigrants from high TB-burden countries, patients with end-stage renal disease, and the immunosuppressed, now defined as further vulnerable groups, no consistent recommendation can be taken from the literature with respect to cost effectiveness of screening and treating LTBI. When the concept of a fixed willingness-to-pay (WTP) threshold as a prerequisite for final categorization was used, the sums ranged between 'no specification' and US$100,000 per quality-adjusted life-year.

CONCLUSIONS

To date, incremental cost-effectiveness analyses on PT in groups at high risk for TB progression, other than contacts, are surprisingly scarce. The variation found between studies likely reflects variations in the major epidemiologic factors, particularly in the estimates on the accuracy of the tuberculin skin test (TST) and interferon-gamma release assays (IGRA) as screening methods used before considering PT. Further research, including explicit evaluation of local epidemiological conditions, test accuracy, and methodology of WTP thresholds, is needed.

Cost-Effectiveness of Screening and Treating Foreign-Born Students for Tuberculosis before Entering the United States

Introduction

The Centers for Disease Control and Prevention is considering implementation of overseas medical screening of student-visa applicants to reduce the numbers of active tuberculosis cases entering the United States.

Objective

To evaluate the costs, cases averted, and cost-effectiveness of screening for, and treating, tuberculosis in United States-bound students from countries with varying tuberculosis prevalence.

Methods

Costs and benefits were evaluated from two perspectives, combined and United States only. The combined perspective totaled overseas and United States costs and benefits from a societal perspective. The United States only perspective was a domestic measure of costs and benefits. A decision tree was developed to determine the cost-effectiveness of tuberculosis screening and treatment from the combined perspective.

Results

From the United States only perspective, overseas screening programs of Chinese and Indian students would prevent the importation of 157 tuberculosis cases annually, and result in $2.7 million in savings. From the combined perspective, screening programs for Chinese students would cost more than $2.8 million annually and screening programs for Indian students nearly $440,000 annually. From the combined perspective, the incremental cost for each tuberculosis case averted by screening Chinese and Indian students was $22,187 and $15,063, respectively. Implementing screening programs for German students would prevent no cases in most years, and would result in increased costs both overseas and in the United States. The domestic costs would occur because public health departments would need to follow up on students identified overseas as having an elevated risk of tuberculosis.

Conclusions

Tuberculosis screening and treatment programs for students seeking long term visas to attend United States schools would reduce the number of tuberculosis cases imported. Implementing screening in high-incidence countries could save the United States millions of dollars annually; however there would be increased costs incurred overseas for students and their families.

Cost-effectiveness analysis of interventions for tuberculosis control: DALYs versus QALYs

The emergence of multi-drug-resistant tuberculosis (MDR-TB) in the European region and the high costs (nearly <euro>536 million) generated by the nearly 72,000 notified TB cases in the EU are the factors driving the need for development and implementation of new tools against TB. In this context, cost-effectiveness analyses applying quality-adjusted life-years (QALYs) or disability-adjusted life-years (DALYs) as outcome measures for economic evaluation of improved approaches to TB control are increasingly important. While the methodology applied to derive the effectiveness data is commonly reported, less information is given regarding the derivation of utility weights in the calculation of QALYs for TB treatment. To date, despite the particular complexities of the disease, TB health effects have not been fully measured and there is no agreement on how disutility of TB disease should be accounted for. Consequently, disutility values in published studies vary considerably, and often appear to lack empirical evidence. As the need for a solid heath-economics rationale for investment in new tools against TB grows, adequate and comprehensive methods for assessing the impairments caused by different types of TB must be developed. Focusing on the assessment of DALYs as a measure of outcome in economic evaluation, we have built an exemplary model calculation applying the original TB data for Germany as reported to the Robert Koch Institute. Our work demonstrates that the use of standard equations provided in the scientific literature probably results in an underestimation of lost DALYs compared with probabilistic techniques. Providing distributions around epidemiological averages, coupled with Monte Carlo simulation to address uncertainty, may result in more realistic values. In line with a previous recommendation by the World Health Organization, it appears worthwhile to consider this more intricate approach to providing healthcare resource allocation decisions, particularly for TB.

Editorial Comment: Cost-Effectiveness Analysis for Prioritization of Limited Public Health Resources - Tuberculosis Interventions in Texas

Public health departments have limited evidence to understand and analyze the costs and benefits of different health programs, including tuberculosis control and prevention programs. The study by Miller et. al addresses this challenge to estimate costs and benefits of tuberculosis prevention programs in Texas and identify cost-effective diagnostic and treatment combinations, thereby improving the evidence-based decision making power of the public health departments.

Effect of the one-child policy on influenza transmission in China: a stochastic transmission model

BACKGROUND

China's one-child-per-couple policy, introduced in 1979, led to profound demographic changes for nearly a quarter of the world's population. Several decades later, the consequences include decreased fertility rates, population aging, decreased household sizes, changes in family structure, and imbalanced sex ratios. The epidemiology of communicable diseases may have been affected by these changes since the transmission dynamics of infectious diseases depend on demographic characteristics of the population. Of particular interest is influenza because China and Southeast Asia lie at the center of a global transmission network of influenza. Moreover, changes in household structure may affect influenza transmission. Is it possible that the pronounced demographic changes that have occurred in China have affected influenza transmission?

METHODS AND FINDINGS

To address this question, we developed a continuous-time, stochastic, individual-based simulation model for influenza transmission. With this model, we simulated 30 years of influenza transmission and compared influenza transmission rates in populations with and without the one-child policy control. We found that the average annual attack rate is reduced by 6.08% (SD 2.21%) in the presence of the one-child policy compared to a population in which no demographic changes occurred. There was no discernible difference in the secondary attack rate, -0.15% (SD 1.85%), between the populations with and without a one-child policy. We also forecasted influenza transmission over a ten-year time period in a population with a two-child policy under a hypothesis that a two-child-per-couple policy will be carried out in 2015, and found a negligible difference in the average annual attack rate compared to the population with the one-child policy.

CONCLUSIONS

This study found that the average annual attack rate is slightly lowered in a population with a one-child policy, which may have resulted from a decrease in household size and the proportion of children in the population.

The effect of a cultural intervention on adherence to latent tuberculosis infection therapy in Latino immigrants

OBJECTIVE

The purpose of this study was to examine the effect of a cultural intervention (CI) on increasing adherence to latent tuberculosis infection (LTBI) therapy among Latino immigrants.

DESIGN AND SAMPLE

This clinical study used a preexperimental design. A nonprobability sample of 86 Latino immigrant clients who were starting LTBI therapy were enrolled in the intervention. The comparison group was an historical sample of 131 clients' records randomly selected from the previous year.

INTERVENTION

The CI, designed by the principal investigator, was delivered by 2 Spanish-speaking interventionist nurses at each of 9 clinic visits. The intervention was based on Latino cultural values and included 5 components.

MEASURES

The patients' adherence was measured by a self-report of the number of pills taken.

RESULTS

The findings of this study were that clients in the CI group took a significantly greater number of doses of INH than those in the historical sample.

CONCLUSIONS

Using a CI to increase adherence to LTBI therapy shows promise for public health nursing practice.

Tuberculosis in Saudi Arabia: can we change the way we deal with the disease?

Infection from Mycobacterium tuberculosis results in the death of three million people worldwide per annum of which an estimated one thousand are in Saudi Arabia. The WHO has set a target for successful treatment of 85% but Saudi Arabia is currently not meeting that target. We believe that the first step in improving the control of tuberculosis in Saudi Arabia is to improve and unify the standards of diagnostic services and laboratories responsible for tuberculosis. This paper reviews the current status and suggests possible improvements.

Direct and indirect costs of tuberculosis among immigrant patients in the Netherlands

BACKGROUND

In low tuberculosis (TB) incidence countries TB affects mostly immigrants in the productive age group. Little empirical information is available about direct and indirect TB-related costs that patients face in these high-income countries. We assessed the direct and indirect costs of immigrants with TB in the Netherlands.

METHODS

A cross-sectional survey at 14 municipal health services and 2 specialized TB hospitals was conducted. Interviews were administered to first or second generation immigrants, 18 years or older, with pulmonary or extrapulmonary TB, who were on treatment for 1-6 months. Out of pocket expenditures and time loss, related to TB, was assessed for different phases of the current TB illness.

RESULTS

In total 60 patients were interviewed. Average direct costs spent by households with a TB patient amounted euro353. Most costs were spent when being hospitalized. Time loss (mean 81 days) was mainly due to hospitalization (19 days) and additional work days lost (60 days), and corresponded with a cost estimation of euro2603.

CONCLUSION

Even in a country with a good health insurance system that covers medication and consultation costs, patients do have substantial extra expenditures. Furthermore, our patients lost on average 2.7 months of productive days. TB patients are economically vulnerable.

The Australasian Society for Infectious Diseases guidelines for the diagnosis, management and prevention of infections in recently arrived refugees: an abridged outline

About 13,000 refugees are currently accepted for migration into Australia each year, many of whom have spent protracted periods living in extremely disadvantaged circumstances. As a result, medical practitioners are increasingly managing recently arrived refugees with acute and chronic infectious diseases. The Australasian Society for Infectious Diseases has formulated guidelines for the diagnosis, management and prevention of infection in newly arrived refugees. This article is an abridged version of the guidelines, which are available in full at <http://www.asid.net.au>. All refugees should be offered a comprehensive health assessment, ideally within 1 month of arrival in Australia, that includes screening for and treatment of tuberculosis, malaria, blood-borne viral infections, schistosomiasis, helminth infection, sexually transmitted infections, and other infections (eg, Helicobacter pylori) as indicated by clinical assessment; and assessment of immunisation status, and catch-up immunisations where appropriate. The assessment can be undertaken by a general practitioner or within a multidisciplinary refugee health clinic, with use of an appropriate interpreter when required. The initial assessment should take place over at least two visits: the first for initial assessment and investigation and the second for review of results and treatment or referral.

Screening for latent tuberculosis infection among undocumented immigrants in Swiss healthcare centres; a descriptive exploratory study

Background

Migration is one of the major causes of tuberculosis in developed countries. Undocumented patients are usually not screened at the border and are not covered by a health insurance increasing their risk of developing the disease unnoticed. Urban health centres could help identify this population at risk. The objective of this study is to assess the prevalence of latent tuberculosis infection (LTBI) and adherence to preventive treatment in a population of undocumented immigrant patients.

Methods

All consecutive undocumented patients that visited two urban healthcare centres for vulnerable populations in Lausanne, Switzerland for the first time were offered tuberculosis screening with an interferon-γ assay. Preventive treatment was offered if indicated. Adherence to treatment was evaluated monthly over a nine month period.

Results

Of the 161 participants, 131 (81.4%) agreed to screening and 125 had complete examinations. Twenty-four of the 125 patients (19.2%; CI95% 12.7;27.2) had positive interferon-γ assay results, two of which had active tuberculosis. Only five patients with LTBI completed full preventive treatments. Five others initiated the treatment but did not follow through.

Conclusion

Screening for tuberculosis infection in this hard-to-reach population is feasible in dedicated urban clinics, and the prevalence of LTBI is high in this vulnerable population. However, the low adherence to treatment is an important public health concern, and new strategies are needed to address this problem.

Cost-effectiveness of Interferon-γ Release Assay Screening for Latent Tuberculosis Infection Treatment in Germany

OBJECTIVES

To assess the cost-effectiveness of the new QuantiFERON-TB Gold In-Tube (QFT-G) [Cellestis; Carnegie, VIC, Australia] assay for screening and treating of persons who have had close contact with tuberculosis (TB) patients and are suspected of having latent tuberculosis infection (LTBI) [hereafter called close-contacts] in Germany.

METHODS

The health and economic outcomes of isoniazid treatment of 20-year-old close-contacts were compared in a Markov model over a period of 20 years, using two different cutoff values for the tuberculin skin test (TST), the QFT-G assay alone, or the QFT-G assay as a confirmatory test for the TST results.

RESULTS

QFT-G assay-based treatment led to cost savings of $542.9 and 3.8 life-days gained per LTBI case. TST-based treatment at a 10-mm induration size cutoff gained $177.4 and 2.0 life-days gained per test-positive contact. When the cutoff induration size for the TST was reduced to 5 mm, the incremental cost-effectiveness ratio fell below the willingness-to-pay threshold ($30,170 per life-years gained) but resulted in unnecessary treatment of 77% of contacts owing to false-positive TST results. Combination with the 5-mm induration size TST cutoff value compared to the results of the QFT-G assay alone reduced the total costs per 1,000 contacts by 1.8% to $222,869. The number treated to prevent 1 TB case was 22 for the two QFT-G assay-based procedures, 40 for the TST at a cutoff induration size of 10 mm, and 96 for the TST at a cutoff induration size of 5 mm. When the sensitivity rates of the TST and the QFT-G assay were compounded, the QFT-G assay strategy alone was slightly less costly (0.6%) than the two-step approach.

CONCLUSIONS

Using the QFT-G assay, but especially combining the QFT-G assay following the TST screening of close-contacts at a cutoff induration size of 5 mm before LTBI treatment is highly cost-effective in reducing the disease burden of TB.