Effectiveness and safety of Levofloxacin containing regimen in the treatment of Isoniazid mono-resistant pulmonary Tuberculosis: a systematic review

Background

We aimed to determine the effectiveness and safety of the Levofloxacin-containing regimen that the World Health Organization is currently recommending for the treatment of Isoniazid mono-resistant pulmonary Tuberculosis.

Methods

Our eligible criteria for the studies to be included were; randomized controlled trials or cohort studies that focused on adults with Isoniazid mono-resistant tuberculosis (HrTB) and treated with a Levofloxacin-containing regimen along with first-line anti-tubercular drugs; they should have had a control group treated with first-line without Levofloxacin; should have reported treatment success rate, mortality, recurrence, progression to multidrug-resistant Tuberculosis. We performed the search in MEDLINE, EMBASE, Epistemonikos, Google Scholar, and Clinical trials registry. Two authors independently screened the titles/abstracts and full texts that were retained after the initial screening, and a third author resolved disagreements.

Results

Our search found 4,813 records after excluding duplicates. We excluded 4,768 records after screening the titles and abstracts, retaining 44 records. Subsequently, 36 articles were excluded after the full-text screening, and eight appeared to have partially fulfilled the inclusion criteria. We contacted the respective authors, and none responded positively. Hence, no articles were included in the meta-analysis.

Conclusion

We found no "quality" evidence currently on the effectiveness and safety of Levofloxacin in treating HrTB.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022290333, identifier: CRD42022290333.

Transmission analysis of a large tuberculosis outbreak in London: a mathematical modelling study using genomic data

Outbreaks of tuberculosis (TB) - such as the large isoniazid-resistant outbreak centred on London, UK, which originated in 1995 - provide excellent opportunities to model transmission of this devastating disease. Transmission chains for TB are notoriously difficult to ascertain, but mathematical modelling approaches, combined with whole-genome sequencing data, have strong potential to contribute to transmission analyses. Using such data, we aimed to reconstruct transmission histories for the outbreak using a Bayesian approach, and to use machine-learning techniques with patient-level data to identify the key covariates associated with transmission. By using our transmission reconstruction method that accounts for phylogenetic uncertainty, we are able to identify 21 transmission events with reasonable confidence, 9 of which have zero SNP distance, and a maximum distance of 3. Patient age, alcohol abuse and history of homelessness were found to be the most important predictors of being credible TB transmitters.

Fluoroquinolones and isoniazid-resistant tuberculosis: implications for the 2018 WHO guidance

Introduction

2018 World Health Organization (WHO) guidelines for the treatment of isoniazid (H)-resistant (Hr) tuberculosis recommend a four-drug regimen: rifampicin (R), ethambutol (E), pyrazinamide (Z) and levofloxacin (Lfx), with or without H ([H]RZE-Lfx). This is used once Hr is known, such that patients complete 6 months of Lfx (≥6[H]RZE-6Lfx). This cohort study assessed the impact of fluoroquinolones (Fq) on treatment effectiveness, accounting for Hr mutations and degree of phenotypic resistance.

Methods

This was a retrospective cohort study of 626 Hr tuberculosis patients notified in London, 2009–2013. Regimens were described and logistic regression undertaken of the association between regimen and negative regimen-specific outcomes (broadly, death due to tuberculosis, treatment failure or disease recurrence).

Results

Of 594 individuals with regimen information, 330 (55.6%) were treated with (H)RfZE (Rf=rifamycins) and 211 (35.5%) with (H)RfZE-Fq. The median overall treatment period was 11.9 months and median Z duration 2.1 months. In a univariable logistic regression model comparing (H)RfZE with and without Fqs, there was no difference in the odds of a negative regimen-specific outcome (baseline (H)RfZE, cluster-specific odds ratio 1.05 (95% CI 0.60–1.82), p=0.87; cluster NHS trust). Results varied minimally in a multivariable model. This odds ratio dropped (0.57, 95% CI 0.14–2.28) when Hr genotype was included, but this analysis lacked power (p=0.42).

Conclusions

In a high-income setting, we found a 12-month (H)RfZE regimen with a short Z duration to be similarly effective for Hr tuberculosis with or without a Fq. This regimen may result in fewer adverse events than the WHO recommendations.

WHO has assessed regimen recommendations for isoniazid-resistant TB to be of very low certainty. The addition of fluoroquinolones to a 12-month (isoniazid, rifamycin, ethambutol, short-duration pyrazinamide) regimen may be unnecessary in certain settings.http://bit.ly/2XoTgNL

Factors associated with isoniazid resistant tuberculosis among human immunodeficiency virus positive patients in Swaziland: a case-control study

Background

Isoniazid resistant tuberculosis is the most prevalent type of resistance in Swaziland and over two-thirds of the isoniazid resistant tuberculosis patients are tuberculosis and human immunodeficiency virus co-infected. The study aimed to determine risk factors associated with isoniazid resistant tuberculosis among human immunodeficiency virus positive patients in Swaziland.

Methods

This was a case-control study conducted in nine healthcare facilities across Swaziland. Cases were patients with isoniazid resistant tuberculosis (including 78 patients with isoniazid mono-resistant tuberculosis, 42 with polydrug-resistant tuberculosis, and 77 with multidrug-resistant tuberculosis). Controls were presumed drug-susceptible tuberculosis patients (n = 203). Multinomial logistic regression was used to determine related factors.

Results

The median time lag from diagnosis to tuberculosis treatment initiation was 50 days for isoniazid mono or poly drug-resistant tuberculosis, 17 days for multidrug-resistant tuberculosis compared to 1 day for drug-susceptible tuberculosis patients. History of previous tuberculosis treatment was positively associated with either isoniazid mono or poly drug-resistant tuberculosis (OR = 7.91, 95% CI: 4.14–15.11) and multidrug-resistant tuberculosis (OR = 12.20, 95% CI: 6.07–24.54). Isoniazid mono or poly resistant tuberculosis patients were more likely to be from rural areas (OR = 2.05, 95% CI: 1.23–3.32) and current heavy alcohol drinkers compared to the drug-susceptible tuberculosis group. Multi drug-resistant tuberculosis patients were more likely to be non-adherent to tuberculosis treatment compared to drug-susceptible tuberculosis group (OR = 3.01, 95% CI: 1.56–5.82).

Conclusion

To prevent and control isoniazid resistant tuberculosis among HIV-positive patients in Swaziland, the tuberculosis program should strengthen the use of rapid diagnostic tests, detect resistance early, promptly initiate supervised tuberculosis treatment and decentralize quality tuberculosis services to the rural areas. Adherence to tuberculosis treatment should be improved.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4384-6) contains supplementary material, which is available to authorized users.

Recent TB transmission, clustering and predictors of large clusters in London, 2010-2012: results from first 3 years of universal MIRU-VNTR strain typing

Background

The incidence of TB has doubled in the last 20 years in London. A better understanding of risk groups for recent transmission is required to effectively target interventions. We investigated the molecular epidemiological characteristics of TB cases to estimate the proportion of cases due to recent transmission, and identify predictors for belonging to a cluster.

Methods

The study population included all culture-positive TB cases in London residents, notified between January 2010 and December 2012, strain typed using 24-loci multiple interspersed repetitive units-variable number tandem repeats. Multivariable logistic regression analysis was performed to assess the risk factors for clustering using sociodemographic and clinical characteristics of cases and for cluster size based on the characteristics of the first two cases.

Results

There were 10 147 cases of which 5728 (57%) were culture confirmed and 4790 isolates (84%) were typed. 2194 (46%) were clustered in 570 clusters, and the estimated proportion attributable to recent transmission was 34%. Clustered cases were more likely to be UK born, have pulmonary TB, a previous diagnosis, a history of substance abuse or alcohol abuse and imprisonment, be of white, Indian, black-African or Caribbean ethnicity. The time between notification of the first two cases was more likely to be <90 days in large clusters.

Conclusions

Up to a third of TB cases in London may be due to recent transmission. Resources should be directed to the timely investigation of clusters involving cases with risk factors, particularly those with a short period between the first two cases, to interrupt onward transmission of TB.

Twenty years and counting: epidemiology of an outbreak of isoniazid-resistant tuberculosis in England and Wales, 1995 to 2014

An outbreak of isoniazid-resistant tuberculosis first identified in London has now been ongoing for 20 years, making it the largest drug-resistant outbreak of tuberculosis documented to date worldwide. We identified culture-confirmed cases with indistinguishable molecular strain types and extracted demographic, clinical, microbiological and social risk factor data from surveillance systems. We summarised changes over time and used kernel-density estimation and k-function analysis to assess geographic clustering. From 1995 to 2014, 508 cases were reported, with a declining trend in recent years. Overall, 70% were male (n = 360), 60% born in the United Kingdom (n = 306), 39% white (n = 199), and 26% black Caribbean (n = 134). Median age increased from 25 years in the first 5 years to 42 in the last 5. Approximately two thirds of cases reported social risk factors: 45% drug use (n = 227), 37% prison link (n = 189), 25% homelessness (n = 125) and 13% alcohol dependence (n = 64). Treatment was completed at 12 months by 52% of cases (n = 206), and was significantly lower for those with social risk factors (p < 0.05), but increased over time for all patients (p < 0.05). The outbreak remained focused in north London throughout. Control of this outbreak requires continued efforts to prevent and treat further active cases through targeted screening and enhanced case management.

Multiple large clusters of tuberculosis in London: a cross-sectional analysis of molecular and spatial data

Large outbreaks of tuberculosis (TB) represent a particular threat to disease control because they reflect multiple instances of active transmission. The extent to which long chains of transmission contribute to high TB incidence in London is unknown. We aimed to estimate the contribution of large clusters to the burden of TB in London and identify risk factors.

We identified TB patients resident in London notified between 2010 and 2014, and used 24-locus mycobacterial interspersed repetitive units–variable number tandem repeat strain typing data to classify cases according to molecular cluster size. We used spatial scan statistics to test for spatial clustering and analysed risk factors through multinomial logistic regression.

TB isolates from 7458 patients were included in the analysis. There were 20 large molecular clusters (with n>20 cases), comprising 795 (11%) of all cases; 18 (90%) large clusters exhibited significant spatial clustering. Cases in large clusters were more likely to be UK born (adjusted odds ratio 2.93, 95% CI 2.28–3.77), of black-Caribbean ethnicity (adjusted odds ratio 3.64, 95% CI 2.23–5.94) and have multiple social risk factors (adjusted odds ratio 3.75, 95% CI 1.96–7.16).

Large clusters of cases contribute substantially to the burden of TB in London. Targeting interventions such as screening in deprived areas and social risk groups, including those of black ethnicities and born in the UK, should be a priority for reducing transmission.

Large clusters contribute substantially to the burden of tuberculosis in London, indicating ongoing transmissionhttp://ow.ly/3xk23068P6w

Isoniazid Mono-Resistant Tuberculosis: Impact on Treatment Outcome and Survival of Pulmonary Tuberculosis Patients in Southern Mexico 1995-2010

Background

Isoniazid mono-resistance (IMR) is the most common form of mono-resistance; its world prevalence is estimated to range between 0.0 to 9.5% globally. There is no consensus on how these patients should be treated.

Objective

To describe the impact of IMR tuberculosis (TB) on treatment outcome and survival among pulmonary TB patients treated under programmatic conditions in Orizaba, Veracruz, Mexico.

Materials and Methods

We conducted a prospective cohort study of pulmonary TB patients in Southern Mexico. From 1995 to 2010 patients with acid-fast bacilli or culture proven Mycobacterium tuberculosis in sputum samples underwent epidemiological, clinical and microbiological evaluation. We included patients who harbored isoniazid mono-resistant (IMR) strains and patients with strains susceptible to isoniazid, rifampicin, ethambutol and streptomycin. All patients were treated following Mexican TB Program guidelines. We performed annual follow-up to ascertain treatment outcome, recurrence, relapse and mortality.

Results

Between 1995 and 2010 1,243 patients with pulmonary TB were recruited; 902/1,243 (72.57%) had drug susceptibility testing; 716 (79.38%) harbored pan-susceptible and 88 (9.75%) IMR strains. Having any contact with a person with TB (adjusted odds ratio (aOR)) 1.85, 95% Confidence interval (CI) 1.15–2.96) and homelessness (adjusted odds ratio (aOR) 2.76, 95% CI 1.08–6.99) were associated with IMR. IMR patients had a higher probability of failure (adjusted hazard ratio (HR) 12.35, 95% CI 3.38–45.15) and death due to TB among HIV negative patients (aHR 3.30. 95% CI 1.00–10.84). All the models were adjusted for socio-demographic and clinical variables.

Conclusions

The results from our study provide evidence that the standardized treatment schedule with first line drugs in new and previously treated cases with pulmonary TB and IMR produces a high frequency of treatment failure and death due to tuberculosis. We recommend re-evaluating the optimal schedule for patients harboring IMR. It is necessary to strengthen scientific research for the evaluation of alternative treatment schedules in similar settings.

Whole Genome Sequence Analysis of a Large Isoniazid-Resistant Tuberculosis Outbreak in London: A Retrospective Observational Study

BACKGROUND

A large isoniazid-resistant tuberculosis outbreak centred on London, United Kingdom, has been ongoing since 1995. The aim of this study was to investigate the power and value of whole genome sequencing (WGS) to resolve the transmission network compared to current molecular strain typing approaches, including analysis of intra-host diversity within a specimen, across body sites, and over time, with identification of genetic factors underlying the epidemiological success of this cluster.

METHODS AND FINDINGS

We sequenced 344 outbreak isolates from individual patients collected over 14 y (2 February 1998-22 June 2012). This demonstrated that 96 (27.9%) were indistinguishable, and only one differed from this major clone by more than five single nucleotide polymorphisms (SNPs). The maximum number of SNPs between any pair of isolates was nine SNPs, and the modal distance between isolates was two SNPs. WGS was able to reveal the direction of transmission of tuberculosis in 16 cases within the outbreak (4.7%), including within a multidrug-resistant cluster that carried a rare rpoB mutation associated with rifampicin resistance. Eleven longitudinal pairs of patient pulmonary isolates collected up to 48 mo apart differed from each other by between zero and four SNPs. Extrapulmonary dissemination resulted in acquisition of a SNP in two of five cases. WGS analysis of 27 individual colonies cultured from a single patient specimen revealed ten loci differed amongst them, with a maximum distance between any pair of six SNPs. A limitation of this study, as in previous studies, is that indels and SNPs in repetitive regions were not assessed due to the difficulty in reliably determining this variation.

CONCLUSIONS

Our study suggests that (1) certain paradigms need to be revised, such as the 12 SNP distance as the gold standard upper threshold to identify plausible transmissions; (2) WGS technology is helpful to rule out the possibility of direct transmission when isolates are separated by a substantial number of SNPs; (3) the concept of a transmission chain or network may not be useful in institutional or household settings; (4) the practice of isolating single colonies prior to sequencing is likely to lead to an overestimation of the number of SNPs between cases resulting from direct transmission; and (5) despite appreciable genomic diversity within a host, transmission of tuberculosis rarely results in minority variants becoming dominant. Thus, whilst WGS provided some increased resolution over variable number tandem repeat (VNTR)-based clustering, it was insufficient for inferring transmission in the majority of cases.

Genetic variation in Mycobacterium tuberculosis isolates from a London outbreak associated with isoniazid resistance

BACKGROUND

The largest outbreak of isoniazid-resistant (INH-R) Mycobacterium tuberculosis in Western Europe is centred in North London, with over 400 cases diagnosed since 1995. In the current study, we evaluated the genetic variation in a subset of clinical samples from the outbreak with the hypothesis that these isolates have unique biological characteristics that have served to prolong the outbreak.

METHODS

Fitness assays, mutation rate estimation, and whole-genome sequencing were performed to test for selective advantage and compensatory mutations.

RESULTS

This detailed analysis of the genetic variation of these INH-R samples suggests that this outbreak consists of successful, closely related, circulating strains with heterogeneous resistance profiles and little or no associated fitness cost or impact on their mutation rate.

CONCLUSIONS

Specific deletions and SNPs could be a peculiar feature of these INH-R M. tuberculosis isolates, and could potentially explain their persistence over the years.

Towards better guidance on caseload thresholds to promote positive tuberculosis treatment outcomes: a cohort study

BACKGROUND

In low-incidence countries, clinical experience of tuberculosis is becoming more limited, with potential consequences for patient outcomes. In 2007, the Department of Health released a guidance 'toolkit' recommending that tuberculosis patients in England should not be solely managed by clinicians who see fewer than 10 cases per year. This caseload threshold was established to try to improve treatment outcomes and reduce transmission, but was not evidence based. We aimed to assess the association between clinician or hospital caseload and treatment outcomes, as well as the relative suitability of making recommendations using each caseload parameter.

METHODS

Demographic and clinical data for tuberculosis cases in England notified to Public Health England's Enhanced Tuberculosis Surveillance system between 2003 and 2012 were extracted. Mean clinician and hospital caseload over the past 3 years were calculated and treatment outcomes grouped into good/neutral and unfavourable. Caseloads over time and their relationship with outcomes were described and analysed using random effects logistic regression, adjusted for clustering.

RESULTS

In a fully adjusted multivariable model (34,707 cases)there was very strong evidence that management of tuberculosis by clinicians with fewer than 10 cases per year was associated with greater odds of an unfavourable outcome compared to clinicians who managed greater numbers of cases (cluster-specific odds ratio, 1.14; 95 % confidence interval, 1.05-1.25; P = 0.002). The relationship between hospital caseload and treatment outcomes was more complex and modified by a patient's place of birth and ethnicity. The clinician caseload association held after adjustment for hospital caseload and when the clinician caseload threshold was reduced down to one.

CONCLUSIONS

Despite the relative ease of making recommendations at the hospital level and the greater reliability of recorded hospital versus named clinician, our results suggest that clinician caseload thresholds are more suitable for clinical guidance. The current recommended clinician caseload threshold is functional. Sensitivity analyses reducing the threshold indicated that clinical experience is pertinent even at very low average caseloads, which is encouraging for low burden settings.

Mutation profiling for detection of isoniazid resistance in Mycobacterium tuberculosis clinical isolates

OBJECTIVES

Progress in the detection of drug-resistant TB has been underpinned by the development and implementation of new, reliable and rapid diagnostic tools. These rely mostly on the detection of specific mutations conferring resistance to anti-TB drugs. The aim of this study was to search for mutations associated with isoniazid resistance among Mycobacterium tuberculosis clinical isolates.

METHODS

A collection of 150 M. tuberculosis strains, including 50 MDR, 50 isoniazid-monoresistant and 50 pan-susceptible strains, was used. For all the strains, seven structural genes (katG, inhA, ahpC, kasA, ndh, nat and mshA) and two regulatory regions (mabA-inhA promoter and oxyR-ahpC intergenic region) were PCR amplified and sequenced in their entirety.

RESULTS

Sixty-six distinct mutations were detected at all nine loci investigated, accounting for 109 (72.7%) of the strains tested. The number of strains with any mutation among the MDR, isoniazid-monoresistant and pan-susceptible groups was 49 (98%), 37 (74%) and 23 (46%), respectively. Mutations in the katG gene predominated, with 29 different types distributed among 46 (92%) MDR, 31 (62%) isoniazid-monoresistant and 2 (4%) pan-susceptible strains. Twenty-nine and 19 mutations were found exclusively in MDR and isoniazid-monoresistant strains, respectively.

CONCLUSIONS

This study revealed 17 mutations, previously unreported, that might be of potential use as new surrogate markers of isoniazid resistance. Their diagnostic accuracy needs to be confirmed on larger strain samples and from different geographical settings. For isoniazid resistance detection, molecular approaches should still be a complement to rather than a replacement for conventional drug susceptibility testing. This is supported by the lack of mutations in any of the nine genetic loci investigated in 18 isoniazid-resistant strains from this study.

Isoniazid-resistant tuberculosis in Birmingham, United Kingdom, 1999-2010

BACKGROUND

There have been few studies on risk factors and treatment outcomes of isoniazid (H)-resistant tuberculosis (TB), and optimal treatment regimens are debated.

AIM

: To identify risk factors for H-resistant TB, describe treatment regimens and compare these to national guidelines and describe short-term outcomes of H-resistant TB in Birmingham, UK.

DESIGN

Retrospective case series.

METHODS

Cases of H-resistant tuberculosis in Birmingham between January 1999 and December 2010 (n = 89) were compared with drug-susceptible cases (n = 2497). Treatment regimens and outcomes at 12 months from diagnosis were evaluated by case note review.

RESULTS

No independent predictors for H-resistant TB were found. For 76/89 (85%) patients with full treatment details available, median treatment duration was 11 months (interquartile range 9-12 months). Only 27/72 (38%) patients with H-monoresistance were treated in line with national guidelines. A further 14/72 (19%) were treated according to other recognized guidelines. Overall treatment success was 75/89 (84%). Treatment failure occurred in 6/89 (7%) patients, all developed multi-drug resistance. Poor adherence was documented in these patients and use of a non-standard regimen in one patient was not thought to have contributed to treatment failure.

CONCLUSIONS

No discriminating risk factors for early detection of H-resistant TB were found. Treatment regimens in clinical practice were highly varied. H-resistance can drive MDR-TB when there is evidence or suspicion of poor adherence. A low threshold for enhanced case management with directly observed therapy is warranted in this group.

Drug resistance among tuberculosis cases in the European Union and European Economic Area, 2007 to 2012

Binary file ES_Abstracts_Final_ECDC.txt matches

Epidemiology of tuberculosis in big cities of the European Union and European Economic Area countries

This cross-sectional survey aimed to examine the epidemiology of tuberculosis (TB) in European Union (EU) and European Economic Area (EEA) cities with populations greater than 500,000. National TB programme managers were asked to provide data on big city population size, total number of notified TB cases in big cities and national notification rate for 2009. A rate ratio was calculated using the big city TB notification rate as a numerator and country TB notification rate, excluding big city TB cases and population, as a denominator. Twenty of the 30 EU/EEA countries had at least one big city. Pooled rate ratios were 2.5, 1.0, and 0.7 in low-, intermediate- and high-incidence countries respectively. In 15 big cities, all in low-incidence countries, rate ratios were twice the national notification rate. These data illustrate the TB epidemiology transition, a situation whereby TB disease concentrates in big cities as national incidence falls, most likely as a result of the higher concentration of risk groups found there. This situation requires targeted interventions and we recommend that big city TB data, including information about patients' risk factors, are collected and analysed systematically, and that successful interventions are shared.

Transmission of multidrug-resistant tuberculosis in the UK: a cross-sectional molecular and epidemiological study of clustering and contact tracing

BACKGROUND

Between 2000 and 2012 the number of multidrug-resistant (MDR) tuberculosis cases in the UK increased from 28 per year to 81 per year. We investigated the proportion of MDR tuberculosis cases arising from transmission in the UK and associated risk factors.

METHOD

We identified patients with MDR tuberculosis notified in England, Wales, and Northern Ireland between Jan 1, 2004, and Dec 31, 2007, by linking national laboratory and surveillance data. Data for laboratory isolates, including drug sensitivities and 24-mycobacterial interspersed repetitive-unit-variable-number tandem repeat (MIRU-VNTR) typing were obtained routinely from the National Tuberculosis Reference laboratories as part of national tuberculosis surveillance. We investigated clusters of cases with indistinguishable MIRU-VNTR profiles to identify epidemiological links. We calculated transmission using the n-1 method and established associated risk factors by logistic regression. We also assessed the likelihood of transmission to additional secondary active tuberculosis cases, identified through conventional contact tracing.

FINDINGS

204 patients were diagnosed with MDR tuberculosis in the study period; 189 (92·6%) had an MIRU-VNTR profile. We identified 12 clusters containing 40 individuals and 149 unique strains. The proportion of cases attributable to recent transmission, on the basis of molecular data, was 15% (40 cases clustered-12 clusters/189 with a strain type). The proportion of cases attributable to recent transmission (ie, transmission within the UK) after adjustment for epidemiological links was 8·5% (22 cases with epidemiological links-six clusters/189 cases with a strain type). Being UK born (odds ratio 4·81; 95% CI 2·03-11·36, p=0·0005) and illicit drug use (4·75; 1·19-18·96, p=0·026) were significantly associated with clustering. The most common transmission setting was the household but 21 of 22 of epidemiological links were missed by conventional contact tracing. 13 secondary active tuberculosis cases identified by conventional contact tracing were mostly contacts of patients with MDR tuberculosis from countries of high tuberculosis burden. 11 (85%) of 13 shared the same country of birth as the index case, of whom ten did not share a strain type or drug resistance pattern.

INTERPRETATION

Transmission of MDR tuberculosis in the UK is low and associated with being UK born or illicit drug use. MIRU-VNTR typing with cluster investigation was more successful at identifying transmission events than conventional contact tracing. Individuals with tuberculosis who have had contact with a known MDR tuberculosis source case from a country of high tuberculosis burden should have drug-sensitivity testing on isolates to ensure appropriate treatment is given.

FUNDING

Public Health England.