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18 results
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Country-specific approaches to latent tuberculosis screening targeting migrants in EU/EEA* countries: A survey of national experts, September 2019 to February 2020
BackgroundMigrants in low tuberculosis (TB) incidence countries in the European Union (EU)/European Economic Area (EEA) are an at-risk group for latent tuberculosis infection (LTBI) and are increasingly included in LTBI screening programmes.
AimTo investigate current approaches and implement LTBI screening in recently arrived migrants in the EU/EEA and Switzerland.
MethodsAt least one TB expert working at a national level from the EU/EEA and one TB expert from Switzerland completed an electronic questionnaire. We used descriptive analyses to calculate percentages, and framework analysis to synthesise free-text responses.
ResultsExperts from 32 countries were invited to participate (30 countries responded): 15 experts reported an LTBI screening programme targeting migrants in their country; five reported plans to implement one in the near future; and 10 reported having no programme. LTBI screening was predominantly for asylum seekers (n = 12) and refugees (n = 11). Twelve countries use ‘country of origin’ as the main eligibility criteria. The countries took similar approaches to diagnosis and treatment but different approaches to follow-up. Six experts reported that drop-out rates in migrants were higher compared with non-migrant groups. Most of the experts (n = 22) called for a renewed focus on expanding efforts to screen for LTBI in migrants arriving in low-incidence countries.
ConclusionWe found a range of approaches to LTBI screening of migrants in the EU/EEA and Switzerland. Findings suggest a renewed focus is needed to expand and strengthen efforts to meaningfully include migrants in these programmes, in order to meet regional and global elimination targets for TB.
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Pregnancy and post-partum tuberculosis; a nationwide register-based case–control study, Denmark, 1990 to 2018
BackgroundPregnancy increases the risk of tuberculosis (TB), however, data on TB epidemiology in pregnant women are limited.
AimTo guide possible interventions, we analysed risk factors for TB in pregnant and post-partum women.
MethodsWe conducted a nationwide retrospective register-based case–control study from January 1990 to December 2018 in Denmark. Cases were women diagnosed with TB during their pregnancy or in the post-partum period. We selected two control groups: pregnant or post-partum women without TB, and non-pregnant women with TB. Differences were assessed by chi-squared or Fisher’s exact test. Risk factors for TB were identified through logistic regression and estimated by odds ratio (OR).
ResultsWe identified 392 cases, including 286 pregnant and 106 post-partum women. Most were migrants (n = 366; 93%) with a shorter median time spent in Denmark (2.74 years; interquartile range (IQR): 1.52–4.64) than non-pregnant TB controls (3.98 years; IQR: 1.43–8.51). Cases less likely had a Charlson comorbidity index ≥ 2compared with non-pregnant TB controls (p < 0.0001), and had no increased risk of severe disease (p = 0.847). Migrants from other World Health Organization regions than Europe, especially Africa (OR: 187; 95%CI: 125–281) had persistently higher odds of TB.
ConclusionsIn Denmark, the risk of TB in pregnant and post-partum women is increased in migrant women who have stayed in the country a median time of approximately 3 years. We recommend increased focus on TB risk during pregnancy and suggest evaluating targeted TB screening of selected at-risk pregnant women to promote early case finding and prevent TB among mothers and their newborn children.
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Recurrent tuberculosis in the Netherlands – a 24-year follow-up study, 1993 to 2016
More LessBackgroundNot all treated tuberculosis (TB) patients achieve long-term recovery and reactivation rates reflect effectiveness of TB treatment.
AimWe aimed to estimate rates and risk factors of TB reactivation and reinfection in patients treated in the Netherlands, after completed or interrupted treatment.
MethodsRetrospective cohort study of TB patients with available DNA fingerprint data, registered in the Netherlands Tuberculosis register (NTR) between 1993 and 2016. Reactivation was defined as an identical, and reinfection as a non-identical Mycobacterium tuberculosis strain in sequential episodes.
ResultsReactivation rate was 55/100,000 person-years (py) for patients who completed, and 318/100,000 py for patients who interrupted treatment. The risk of reactivation was highest in the first 5 years after treatment in both groups. The incidence rate of reactivation was 228/100,000 py in the first 2 years and 57/100,000 py 2–5 years after completed treatment. The overall rate of reinfection was 16/100,000 py. Among those who completed treatment, patients with male sex, mono or poly rifampicin-resistant TB and a previous TB episode had significantly higher risk of reactivation. Extrapulmonary TB was associated with a lower risk. Among patients who interrupted treatment, directly observed treatment (DOT) and being an undocumented migrant or people experiencing homelessness were associated with a higher risk of reactivation.
ConclusionsBoth patients who completed or interrupted TB treatment should be considered as risk groups for reactivation for at least 2–5 years after treatment. They patients should be monitored and guidelines should be in place to enhance early detection of recurrent TB.
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Tuberculosis contact investigation following the stone-in-the-pond principle in the Netherlands – Did adjusted guidelines improve efficiency?
More LessBackgroundIn low tuberculosis (TB) incidence countries, contact investigation (CI) requires not missing contacts with TB infection or disease without unnecessarily evaluating non-infected contacts.
AimWe assessed whether updated guidelines for the stone-in-the-pond principle and their promotion improved CI practices.
MethodsThis retrospective study used surveillance data to compare CI outcomes before (2011–2013) and after (2014–2016) the guideline update and promotion. Using negative binomial regression and logistic regression models, we compared the number of contacts invited for CI per index patient, the number of CI scaled-up according to the stone-in-the-pond principle, the TB and latent TB infection (LTBI) testing coverage, and yield.
ResultsPre and post update, 1,703 and 1,489 index patients were reported, 27,187 and 21,056 contacts were eligible for CI, 86% and 89% were tested for TB, and 0.70% and 0.73% were identified with active TB, respectively. Post update, the number of casual contacts invited per index patient decreased statistically significantly (RR = 0.88; 95% CI: 0.79–0.98), TB testing coverage increased (OR = 1.4; 95% CI: 1.2–1.7), and TB yield increased (OR = 2.0; 95% CI: 1.0–3.9). The total LTBI yield increased from 8.8% to 9.8%, with statistically significant increases for casual (OR = 1.2; 95% CI: 1.0–1.5) and community contacts (OR = 2.0; 95% CI: 1.6–3.2). The proportion of CIs appropriately scaled-up to community contacts increased statistically significantly (RR = 1.8; 95% CI: 1.3–2.6).
ConclusionThis study shows that promoting evidence-based CI guidelines strengthen the efficiency of CIs without jeopardising effectiveness. These findings support CI is an effective TB elimination intervention.
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Early COVID-19 pandemic’s toll on tuberculosis services, WHO European Region, January to June 2020
BackgroundEssential health services, including for tuberculosis (TB), are being affected by public health and social measures (PHSM) introduced to control COVID-19. In many settings, TB resources, facilities and equipment are being redirected towards COVID-19 response.
AimWe sought to assess the COVID-19 pandemic’s impact on TB services in the World Health Organization (WHO) European Region.
MethodsThe fifty-three European Region Member States were asked to report qualitative and quantitative data in quarter one and two (Q1 and Q2) 2020. TB notifications were triangulated with the severity score on domestic movement restrictions to assess how they may have influenced TB detection.
ResultsTwenty-nine countries reported monthly TB notifications for the first half of 2019 and 2020. TB notifications decreased by 35.5% during Q2 2020 compared with Q2 2019, which is six-fold more than the average annual decrease of 5.1% documented during 2015–2019. The number of patients enrolled in rifampicin-resistant/multidrug-resistant TB treatment also decreased dramatically in Q2 2020, by 33.5%. The highest movement restriction severity score was observed between April and May 2020, which coincided with the highest observed decrease in TB notifications.
ConclusionA decrease in TB detection and enrolment to treatment may cause increases in TB burden and threatens the Region’s ability to reach the TB targets of the 2030 Sustainable Development Goals, still this might be mitigated with rapid restoration of TB services and the implementation of targeted interventions during periods with severe PHSM in place, such as those introduced in response to the COVID-19 pandemic.
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Impact of the COVID-19 pandemic on tuberculosis national reference laboratory services in the WHO European Region, March to November 2020
We assessed the impact of COVID-19 on diagnostic services for tuberculosis (TB) by national reference laboratories in the WHO European Region. Of 35 laboratories, 30 reported declines in TB sample numbers, amounting up to > 50% of the pre-COVID-19 volumes. Sixteen reported reagent or consumable shortages. Nineteen reallocated ressources to SARS-CoV-2 testing, resulting in an overall increase in workload, largely without a concomitant increase in personnel (n = 14). This poses a risk to meeting the 2025 milestones of the End TB Strategy.
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Improving tuberculosis surveillance by detecting international transmission using publicly available whole genome sequencing data
IntroductionImproving the surveillance of tuberculosis (TB) is especially important for multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. The large amount of publicly available whole genome sequencing (WGS) data for TB gives us the chance to re-use data and to perform additional analyses at a large scale.
AimWe assessed the usefulness of raw WGS data of global MDR/XDR Mycobacterium tuberculosis isolates available from public repositories to improve TB surveillance.
MethodsWe extracted raw WGS data and the related metadata of M. tuberculosis isolates available from the Sequence Read Archive. We compared this public dataset with WGS data and metadata of 131 MDR- and XDR M. tuberculosis isolates from Germany in 2012 and 2013.
ResultsWe aggregated a dataset that included 1,081 MDR and 250 XDR isolates among which we identified 133 molecular clusters. In 16 clusters, the isolates were from at least two different countries. For example, Cluster 2 included 56 MDR/XDR isolates from Moldova, Georgia and Germany. When comparing the WGS data from Germany with the public dataset, we found that 11 clusters contained at least one isolate from Germany and at least one isolate from another country. We could, therefore, connect TB cases despite missing epidemiological information.
ConclusionWe demonstrated the added value of using WGS raw data from public repositories to contribute to TB surveillance. Comparing the German with the public dataset, we identified potential international transmission events. Thus, using this approach might support the interpretation of national surveillance results in an international context.
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Completeness of tuberculosis (TB) notification: inventory studies and capture-recapture analyses, six European Union countries, 2014 to 2016
BackgroundProgress towards the World Health Organization’s End TB Strategy is monitored by assessing tuberculosis (TB) incidence, often derived from TB notification, assuming complete case detection and reporting. This assumption is unlikely to hold in many settings, including European Union (EU) countries.
AimWe aimed to assess observed and estimated completeness of TB notification through inventory studies and capture–recapture (CRC) methodology in six EU countries: Croatia, Denmark, Finland, the Netherlands, Portugal Slovenia.
MethodsWe performed record linkage, case ascertainment and CRC analyses of data collected retrospectively from at least three national TB-related registers in each country between 2014 and 2016.
ResultsObserved completeness of TB notification by inventory studies was 73.9% in Croatia, 98.7% in Denmark, 83.6% in Finland, 81.6% in the Netherlands, 85.8% in Portugal and 100% in Slovenia. Subsequent CRC analysis estimated completeness of TB notification to be 98.4% in Denmark, 76.5% in Finland and 77.0% in Portugal. In Croatia, CRC analyses produced implausible results while in the Netherlands and Slovenia, it was methodologically considered not meaningful.
ConclusionInventory studies and CRC methodology suggest a TB notification completeness between 73.9% and 100% in the six EU countries. Mandatory reporting by clinicians and laboratories, and cross-checking of registers, strongly contributes to accurate notification rates, but hospital episode registers likely contain a considerable proportion of false-positive TB records and are thus less useful. Further strengthening routine surveillance to count TB cases, i.e. incidence, accurately by employing record-linkage of high-quality TB registers should make CRC studies obsolete in EU countries.
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Tuberculosis treatment outcomes of notified cases: trends and determinants of potential unfavourable outcome, France, 2008 to 2014
More LessBackgroundSurveillance of tuberculosis (TB) treatment outcome, for which reporting has been mandatory in France since 2007, is a key component of TB control.
AimWe aimed to present surveillance data for non-multidrug-resistant (MDR) cases reported between 2008 and 2014, and identify factors associated with potentially unfavourable treatment outcome.
MethodsPatients were classified according to their treatment outcome 12 months after beginning treatment. Poisson regression with a robust error variance was used to investigate factors associated with potentially unfavourable treatment outcome. Missing data were handled using multiple imputation.
ResultsA total of 22,526 cases were analysed for treatment outcome. Information available on treatment outcome increased between 2008 (60%) and 2014 (71%) (p < 0.001). During this period, 74.1% of cases completed treatment, increasing from 73.0% in 2008 to 76.9% in 2014 (p < 0.001). This proportion was 74.0% in culture-positive pulmonary cases. Overall, 19.8% of cases had a potentially unfavourable outcome, including lost-to-follow-up, transferred out, still on treatment, death related to TB and interrupted treatment. Potentially unfavourable outcome was significantly associated with TB severity, residing in congregate settings, homelessness, being a smear-positive pulmonary case, being born abroad and residing in France for < 2 years, history of previous anti-TB treatment and age > 85 years.
ConclusionMonitoring of treatment outcome is improving over time. The increase in treatment completion over time suggests improved case management. However, treatment outcome monitoring needs to be strengthened in cases belonging to population groups where the percentage of unfavourable outcome is the highest and in cases where surveillance data shows poorer documented follow-up.
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Trends in tuberculosis notification and mortality and factors associated with treatment outcomes in Serbia, 2005 to 2015
BackgroundPreviously a country with medium tuberculosis (TB) burden, Serbia almost reached a low TB burden during the period 2005 to 2015.
AimThe aim of this study was to analyse the trends in notification rates and treatment success rates as well as to identify predictors of treatment outcomes.
MethodsWe performed a trend analysis and logistic regression analysis of 17,441 TB cases registered from 2005 to 2015 in all health facilities in Serbia, to identify predictors of treatment success, loss to follow-up and mortality.
ResultsFrom 2005 to 2015, TB notification rate and mortality in Serbia decreased but treatment success remained below the global target. Loss to follow-up was associated with retreatment (odds ratio (OR) = 2.38; 95% confidence interval (CI): 2.08–2.77), male sex (OR = 1.57; 95% CI: 1.39–1.79), age younger than 65 years (OR = 1.37; 95% CI: 1.20–1.51), lower education level (OR = 2.57; 95% CI: 1.74–3.80) and pulmonary TB (OR = 1.28; 95% CI: 1.06–1.56). Deaths were more frequent in retreatment cases (OR = 1.39; 95% CI: 1.12–1.61), male patients (OR = 1.34; 95% CI: 1.19–1.52), those 65 years and older (OR = 4.34; 95% CI: 4.00–5.00), those with lower education level (OR = 1.63; 95% CI: 1.14–2.33) and pulmonary TB (OR = 2.24; 95% CI: 1.78–2.83).
ConclusionsSpecial interventions should be implemented to address groups at risk of poor treatment outcome.
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Towards standardisation: comparison of five whole genome sequencing (WGS) analysis pipelines for detection of epidemiologically linked tuberculosis cases
BackgroundWhole genome sequencing (WGS) is a reliable tool for studying tuberculosis (TB) transmission. WGS data are usually processed by custom-built analysis pipelines with little standardisation between them.
AimTo compare the impact of variability of several WGS analysis pipelines used internationally to detect epidemiologically linked TB cases.
MethodsFrom the Netherlands, 535 Mycobacterium tuberculosis complex (MTBC) strains from 2016 were included. Epidemiological information obtained from municipal health services was available for all mycobacterial interspersed repeat unit-variable number of tandem repeat (MIRU-VNTR) clustered cases. WGS data was analysed using five different pipelines: one core genome multilocus sequence typing (cgMLST) approach and four single nucleotide polymorphism (SNP)-based pipelines developed in Oxford, United Kingdom; Borstel, Germany; Bilthoven, the Netherlands and Copenhagen, Denmark. WGS clusters were defined using a maximum pairwise distance of 12 SNPs/alleles.
ResultsThe cgMLST approach and Oxford pipeline clustered all epidemiologically linked cases, however, in the other three SNP-based pipelines one epidemiological link was missed due to insufficient coverage. In general, the genetic distances varied between pipelines, reflecting different clustering rates: the cgMLST approach clustered 92 cases, followed by 84, 83, 83 and 82 cases in the SNP-based pipelines from Copenhagen, Oxford, Borstel and Bilthoven respectively.
ConclusionConcordance in ruling out epidemiological links was high between pipelines, which is an important step in the international validation of WGS data analysis. To increase accuracy in identifying TB transmission clusters, standardisation of crucial WGS criteria and creation of a reference database of representative MTBC sequences would be advisable.
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Estimating the effect of the 2005 change in BCG policy in England: a retrospective cohort study, 2000 to 2015
More LessBackgroundIn 2005 in England, universal Bacillus Calmette–Guérin (BCG) vaccination of school-age children was replaced by targeted BCG vaccination of high-risk neonates.
AimEstimate the impact of the 2005 change in BCG policy on tuberculosis (TB) incidence rates in England.
MethodsWe conducted an observational study by combining notifications from the Enhanced Tuberculosis Surveillance system, with demographic data from the Labour Force Survey to construct retrospective cohorts relevant to both the universal and targeted vaccination between 1 January 2000 and 31 December 2010. We then estimated incidence rates over a 5-year follow-up period and used regression modelling to estimate the impact of the change in policy on TB.
ResultsIn the non-United Kingdom (UK) born, we found evidence for an association between a reduction in incidence rates and the change in BCG policy (school-age incidence rate ratio (IRR): 0.74; 95% credible interval (CrI): 0.61 to 0.88 and neonatal IRR: 0.62; 95%CrI: 0.44 to 0.88). We found some evidence that the change in policy was associated with an increase in incidence rates in the UK born school-age population (IRR: 1.08; 95%CrI: 0.97 to 1.19) and weaker evidence of an association with a reduction in incidence rates in UK born neonates (IRR: 0.96; 95%CrI: 0.82 to 1.14). Overall, we found that the change in policy was associated with directly preventing 385 (95%CrI: −105 to 881) cases.
ConclusionsWithdrawing universal vaccination at school age and targeting vaccination towards high-risk neonates was associated with reduced incidence of TB. This was largely driven by reductions in the non-UK born with cases increasing in the UK born.
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Tuberculosis incidence among migrants according to migrant status: a cohort study, Denmark, 1993 to 2015
BackgroundMigrants account for the majority of tuberculosis (TB) cases in low-incidence countries in western Europe. TB incidence among migrants might be influenced by patterns of migration, but this is not well understood.
AimTo investigate differences in TB risk across migrant groups according to migrant status and region of origin.
MethodsThis prospective cohort study included migrants ≥ 18 years of age who obtained residency in Denmark between 1 January 1993 and 31 December 2015, matched 1:6 to Danish-born individuals. Migrants were grouped according to legal status of residency and region of origin. Incidence rates (IR) and incidence rate ratios (IRR) were estimated by Poisson regression.
ResultsThe cohort included 142,314 migrants. Migrants had significantly higher TB incidence (IR: 120/100,000 person-years (PY); 95% confidence interval (CI): 115–126) than Danish-born individuals (IR: 4/100,000 PY; 95% CI: 3–4). The IRR was significantly higher in all migrant groups compared with Danish-born (p < 0.01). A particularly higher risk was seen among family-reunified to refugees (IRR: 61.8; 95% CI: 52.7–72.4), quota refugees (IRR: 46.0; 95% CI: 36.6–57.6) and former asylum seekers (IRR: 45.3; 95% CI: 40.2–51.1), whereas lower risk was seen among family-reunified to Danish/Nordic citizens (IRR 15.8; 95% CI: 13.6–18.4) and family-reunified to immigrants (IRR: 16.9; 95% CI: 13.5–21.3).
DiscussionAll migrants had higher TB risk compared with the Danish-born population. While screening programmes focus mostly on asylum seekers, other migrant groups with high risk of TB are missed. Awareness of TB risk in all high-risk groups should be strengthened and screening programmes should be optimised.
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Targeting TB or MRSA in Norwegian municipalities during ‘the refugee crisis’ of 2015: a framework for priority setting in screening
IntroductionIn 2015, there was an increase in the number of asylum seekers arriving in Europe. Like in other countries, deciding screening priorities for tuberculosis (TB) and meticillin-resistant Staphylococcus aureus (MRSA) was a challenge. At least five of 428 municipalities chose to screen asylum seekers for MRSA before TB; the Norwegian Institute for Public Health advised against this.
AimTo evaluate the MRSA/TB screening results from 2014 to 2016 and create a generalised framework for screening prioritisation in Norway through simulation modelling.
MethodsThis is a register-based cohort study of asylum seekers using data from the Norwegian Surveillance System for Communicable Diseases from 2014 to 2016. We used survey data from municipalities that screened all asylum seekers for MRSA and denominator data from the Directorate of Immigration. A comparative risk assessment model was built to investigate the outcomes of prioritising between TB and MRSA in screening regimes.
ResultsOf 46,090 asylum seekers, 137 (0.30%) were diagnosed with active TB (notification rate: 300/100,000 person-years). In the municipalities that screened all asylum seekers for MRSA, 13 of 1,768 (0.74%) were found to be infected with MRSA. The model estimated that screening for MRSA would prevent eight MRSA infections while prioritising TB screening would prevent 24 cases of active TB and one death.
ConclusionOur findings support the decision to advise against screening for MRSA before TB among newly arrived asylum seekers. The model was an effective tool for comparing screening priorities and can be applied to other scenarios in other countries.
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High rate of transmission in a pulmonary tuberculosis outbreak in a primary school, north-eastern Italy, 2019
Sandro Cinquetti , Maria Dalmanzio , Elisa Ros , Davide Gentili , Mauro Ramigni , Adriano Grossi , Xanthi D Andrianou , Leonardo Ermanno La Torre , Roberto Rigoli , Pier Giorgio Scotton , Angela Taraschi , Vincenzo Baldo , Giuseppina Napoletano , Francesca Russo , Patrizio Pezzotti , Giovanni Rezza and Antonietta FiliaItaly is a low-incidence country for tuberculosis (TB). We describe a TB outbreak in a primary school in north-eastern Italy, involving 10 cases of active pulmonary disease and 42 cases of latent infection. The index case was detected in March 2019, while the primary case, an Italian-born schoolteacher, was likely infectious since January 2018. Administration of a pre-employment health questionnaire to school staff with sustained contact with children should be considered in low-incidence countries.
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Will we reach the Sustainable Development Goals target for tuberculosis in the European Union/European Economic Area by 2030?
More LessWe assessed progress towards the Sustainable Development Goals target for tuberculosis in the European Union/European Economic Area using the latest tuberculosis (TB) surveillance and Eurostat data. Both the TB notification rate and the number of TB deaths were decreasing before 2015 and the TB notification rate further declined between 2015 and 2017. With the current average decline in notification rate and number of TB deaths however, the EU/EEA will not reach the targets by 2030.
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