A cost-effectiveness evaluation of latent tuberculosis infection screening of a migrant population in Malaysia.

To estimate the costs and benefits of screening for latent tuberculosis infection (LTBI) in a migrant population in Malaysia. An economic model was developed from a Malaysian healthcare perspective to compare QuantiFERON-TB Gold Plus (QuantiFERON) with the tuberculin skin test (TST). A decision tree was used to capture outcomes relating to LTBI screening followed by a Markov model that simulated the lifetime costs and benefits of the patient cohort. The Markov model did not capture the impact of secondary infections. The model included an R shiny interactive interface to allow adaptation to other scenarios and settings. QuantiFERON is both more effective and less costly than TST (dominant). Compared with QuantiFERON, the lifetime risk of developing active TB increases by approximately 40% for TST due to missed LTBI cases during screening (i.e. a higher number of false negative cases for TST). For a migrant population in Malaysia, QuantiFERON is cost-effective when compared with TST. Further research should consider targeted LTBI screening for migrants in Malaysia based on common risk factors.

A systematic review of cost-utility analyses of screening methods in latent tuberculosis infection in high-risk populations.

BACKGROUND: The World Health Organisation (WHO) recommends that testing and treatment for latent tuberculosis infection (LTBI) should be undertaken in high-risk groups using either interferon gamma release assays (IGRAs) or a tuberculin skin test (TST). As IGRAs are more expensive than TST, an assessment of the cost-effectiveness of IGRAs can guide decision makers on the most appropriate choice of test for different high-risk populations. This current review aimed to provide the most up to date evidence on the cost-effectiveness evidence on LTBI testing in high-risk groups-specifically evidence reporting the costs per QALY of different testing strategies. METHODS: A comprehensive search of databases including MEDLINE, EMBASE and NHS-EED was undertaken from 2011 up to March 2021. Studies were screened and extracted by two independent reviewers. The study quality was assessed using the Bias in Economic Evaluation Checklist (ECOBIAS). A narrative synthesis of the included studies was undertaken. RESULTS: Thirty-two studies reported in thirty-three documents were included in this review. Quality of included studies was generally high, although there was a weakness across all studies referencing sources correctly and/or justifying choices of parameter values chosen or assumptions where parameter values were not available. Inclusions of IGRAs in testing strategies was consistently found across studies to be cost-effective but this result was sensitive to underlying LTBI prevalence rates. CONCLUSION: While some concerns remain about uncertainty in parameter values used across included studies, the evidence base since 2010 has grown with modelling approaches addressing the weakness pointed out in previous reviews but still reaching the same conclusion that IGRAs are likely to be cost-effective in high-income countries for high-risk populations. Evidence is also required on the cost-effectiveness of different strategies in low to middle income countries and countries with high TB burden.

Accuracy of interferon gamma release assays for the COVID-19 immunity assessment.

Emerging evidence suggests that T-cells play a significant role in COVID-19 immunity both in the context of natural infection and vaccination. Easy to use IGRA assays including QFN SARS are considered attractive alternatives to more "traditional" but laborious methods for detection of SARS-CoV-2-specific T-cell responses. In our Letter we are proposing explanations to an apparently lower than expected T-cell responses (44 % reactive individuals) reported by Krüttgen et al in a small cohort of healthy double vaccinated individuals. These results could have been affected by reporting raw optical density values instead of calculated Interferon-É£ concentrations which is supported by unexpectedly low mitogen responses in healthy individuals. This study highlights an importance of adhering to good laboratory practice principles as well as overall importance of accurate T-cell immunity assessment using IGRA assays.

Social determinants of tuberculosis in Europe: a prospective ecological study.

Tuberculosis (TB) is considered to be a disease of poverty, since its incidence is exacerbated by socioeconomic factors, inconsistent or partial treatment practices, and immigration from endemic countries. A prospective country level study, using a comprehensive dataset of TB incidence and prevalence taken from countries within the World Health Organization (WHO) European region, was conducted. We employed quintile regression to investigate the prospective association between baseline (measured in 2000) and a nation's wealth, level of egalitarianism, migration rate, health-related lifestyle and social capital with TB incidence and prevalence over a 10-yr period (2000-2009). We found that ∼50% of TB variation is accounted for by a nation's wealth and level of egalitarianism. We observed a negative prospective association between logged gross domestic product and TB rates, and a positive prospective association between income inequality and TB. National income levels per capita and income inequality are important predictors for TB incidence and prevalence in the WHO European region. They account for 50% of country-level variation, indicating the importance of a combined absolute and relative socioeconomic disadvantage in the development of TB. These findings also provide a tool for forecasting potential fluctuations in the level of TB epidemics in the WHO European region, with respect to socioeconomic changes.

Wealth inequality and tuberculosis elimination in Europe.

In Europe, wealth inequality is directly related to tuberculosis (TB) notification (R2 = 0.69), while in countries with lower TB rates, higher proportions of TB cases occur in foreign-born persons. Particularly during times of financial upheaval, efforts to eliminate TB must address social inequality.