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Rationale South African adolescents carry a high tuberculosis disease burden. It is not known if schools are high-risk settings for Mycobacterium tuberculosis (MTB) transmission. Objectives To detect airborne MTB genomic DNA in classrooms. Methods We studied 72 classrooms occupied by 1,836 students in two South African schools. High-volume air filtration was performed for median 40 minutes (interquartile range 35-54) and assayed by droplet digital PCR (ddPCR) targeting MTB Region of Difference 9 (RD9), with concurrent CO2 concentration measurement. Classroom data were benchmarked against public health clinics. Students who consented to individual TB screening completed a questionnaire and sputum collection (Xpert MTB/RIF Ultra) if symptom-positive. Poisson statistics were used for MTB RD9 copy quantification. Measurements and Main Results ddPCR assays were positive in 13/72 (18.1%) classroom and 4/39 (10.3%) clinic measurements (p=0.276). Median ambient CO2 concentration was 886 ppm (IQR 747-1223) in classrooms vs. 490 ppm (IQR 405-587) in clinics (p

Background Tuberculosis (TB) preventive therapy is recommended for all people living with HIV (PLHIV). Despite the elevated risk of TB amongst PLHIV, most of those eligible for preventive therapy would never develop TB. Tests which can identify individuals at greatest risk of disease would allow more efficient targeting of preventive therapy. Methods We used mathematical modelling to estimate the potential impact of using a blood transcriptomic biomarker (RISK11) to target preventive therapy amongst PLHIV. We compared universal treatment to RISK11 targeted treatment and explored the effect of repeat screening of the population with RISK11. Results Annual RISK11 screening, with preventive therapy provided to those testing positive, could avert 26% (95% CI 13–34) more cases over 10 years compared to one round of universal treatment. For the cost per case averted to be lower than universal treatment, the maximum cost of the RISK11 test was approximately 10% of the cost of preventive therapy. The benefit of RISK11 screening may be greatest amongst PLHIV on ART (compared to ART naïve individuals) due to the increased specificity of the test in this group. Conclusions Biomarker targeted preventive therapy may be more effective than universal treatment amongst PLHIV in high incidence settings but would require repeat screening.

Summary Background A rapid, blood-based triage test that allows targeted investigation for tuberculosis at the point of care could shorten the time to tuberculosis treatment and reduce mortality. We aimed to test the performance of a host blood transcriptomic signature (RISK11) in diagnosing tuberculosis and predicting progression to active pulmonary disease (prognosis) in people with HIV in a community setting. Methods In this prospective diagnostic and prognostic accuracy study, adults (aged 18–59 years) with HIV were recruited from five communities in South Africa. Individuals with a history of tuberculosis or household exposure to multidrug-resistant tuberculosis within the past 3 years, comorbid risk factors for tuberculosis, or any condition that would interfere with the study were excluded. RISK11 status was assessed at baseline by real-time PCR; participants and study staff were masked to the result. Participants underwent active surveillance for microbiologically confirmed tuberculosis by providing spontaneously expectorated sputum samples at baseline, if symptomatic during 15 months of follow-up, and at 15 months (the end of the study). The coprimary outcomes were the prevalence and cumulative incidence of tuberculosis disease confirmed by a positive Xpert MTB/RIF, Xpert Ultra, or Mycobacteria Growth Indicator Tube culture, or a combination of such, on at least two separate sputum samples collected within any 30-day period. Findings Between March 22, 2017, and May 15, 2018, 963 participants were assessed for eligibility and 861 were enrolled. Among 820 participants with valid RISK11 results, eight (1%) had prevalent tuberculosis at baseline: seven (2·5%; 95% CI 1·2–5·0) of 285 RISK11-positive participants and one (0·2%; 0·0–1·1) of 535 RISK11-negative participants. The relative risk (RR) of prevalent tuberculosis was 13·1 times (95% CI 2·1–81·6) greater in RISK11-positive participants than in RISK11-negative participants. RISK11 had a diagnostic area under the receiver operating characteristic curve (AUC) of 88·2% (95% CI 77·6–96·7), and a sensitivity of 87·5% (58·3–100·0) and specificity of 65·8% (62·5–69·0) at a predefined score threshold (60%). Of those with RISK11 results, eight had primary endpoint incident tuberculosis during 15 months of follow-up. Tuberculosis incidence was 2·5 per 100 person-years (95% CI 0·7–4·4) in the RISK11-positive group and 0·2 per 100 person-years (0·0–0·5) in the RISK11-negative group. The probability of primary endpoint incident tuberculosis was greater in the RISK11-positive group than in the RISK11-negative group (cumulative incidence ratio 16·0 [95% CI 2·0–129·5]). RISK11 had a prognostic AUC of 80·0% (95% CI 70·6–86·9), and a sensitivity of 88·6% (43·5–98·7) and a specificity of 68·9% (65·3–72·3) for incident tuberculosis at the 60% threshold. Interpretation RISK11 identified prevalent tuberculosis and predicted risk of progression to incident tuberculosis within 15 months in ambulant people living with HIV. RISK11's performance approached, but did not meet, WHO's target product profile benchmarks for screening and prognostic tests for tuberculosis. Funding Bill & Melinda Gates Foundation and the South African Medical Research Council.

Background Tuberculosis (TB) is caused by Mycobacterium tuberculosis (Mtb) infection and is a major public health problem. Clinical challenges include the lack of a blood-based test for active disease. Current blood-based tests, such as QuantiFERON (QFT) do not distinguish active TB disease from asymptomatic Mtb infection. Methods We hypothesized that TruCulture, an immunomonitoring method for whole-blood stimulation, could discriminate active disease from latent Mtb infection (LTBI). We stimulated whole blood from patients with active TB and compared with LTBI donors. Mtb-specific antigens and live bacillus Calmette-Guérin (BCG) were used as stimuli, with direct comparison to QFT. Protein analyses were performed using conventional and digital enzyme-linked immunosorbent assay (ELISA), as well as Luminex. Results TruCulture showed discrimination of active TB cases from LTBI (P < .0001, AUC = .81) compared with QFT (P = .45, AUC = .56), based on an interferon γ (IFNγ) readout after Mtb antigen (Ag) stimulation. This result was replicated in an independent cohort (AUC = .89). In exploratory analyses, TB stratification could be further improved by the Mtb antigen to BCG IFNγ ratio (P < .0001, AUC = .91). Finally, the combination of digital ELISA and transcriptional analysis showed that LTBI donors with high IFNγ clustered with patients with TB, suggesting the possibility to identify subclinical disease. Conclusions TruCulture offers a next-generation solution for whole-blood stimulation and immunomonitoring with the possibility to discriminate active and latent infection., We tested TruCulture, an immunomonitoring tool, to identify active disease from latent Mtb infection. TruCulture showed improved discrimination of tuberculosis cases from LTBI as compared with QuantiFERON. Tuberculosis stratification could be further improved by the Mtb Ag:BCG IFNγ ratio.

Background In human blood, mucosal-associated invariant T (MAIT) cells are abundant T cells that recognize antigens presented on non-polymorphic major histocompatibility complex-related 1 (MR1) molecules. The MAIT cells are activated by mycobacteria, and prior human studies indicate that blood frequencies of MAIT cells, defined by cell surface markers, decline during tuberculosis (TB) disease, consistent with redistribution to the lungs. Methods We tested whether frequencies of blood MAIT cells were altered in patients with TB disease relative to healthy Mycobacterium tuberculosis-exposed controls from Peru and South Africa. We quantified their frequencies using MR1 tetramers loaded with 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil. Results Unlike findings from prior studies, frequencies of blood MAIT cells were similar among patients with TB disease and latent and uninfected controls. In both cohorts, frequencies of MAIT cells defined by MR1-tetramer staining and coexpression of CD161 and the T-cell receptor alpha variable gene TRAV1-2 were strongly correlated. Disease severity captured by body mass index or TB disease transcriptional signatures did not correlate with MAIT cell frequencies in patients with TB. Conclusions Major histocompatibility complex (MHC)-related 1-restrictied MAIT cells are detected at similar levels with tetramers or surface markers. Unlike MHC-restricted T cells, blood frequencies of MAIT cells are poor correlates of TB disease but may play a role in pathophysiology.

Treating tuberculosis (TB) requires a multidrug course of treatment lasting 6 months, or longer for drug-resistant TB, which is difficult to complete and often not well tolerated. Treatment failure and recurrence after end-of-treatment can have devastating consequences, including progressive debilitation, death, the transmission of Mycobacterium tuberculosis – the infectious agent responsible for causing TB – to others, and may be associated with the development of drug-resistant TB. The burden on health systems is important, with severe economic consequences. Vaccines have the potential to serve as immunotherapeutic adjuncts to antibiotic treatment regimens for TB. A therapeutic vaccine for TB patients, administered towards completion of a prescribed course of drug therapy or at certain time(s) during treatment, could improve outcomes through immune-mediated control and even clearance of bacteria, potentially prevent re-infection, and provide an opportunity to shorten and simplify drug treatment regimens. The preferred product characteristics (PPC) for therapeutic TB vaccines described in this document are intended to provide guidance to scientists, funding agencies, public and private sector organizations developing such vaccine candidates. This document presents potential clinical end-points for evidence generation and discusses key considerations about potential clinical development strategies.

Objectives We evaluated longitudinal kinetics of an 11-gene blood transcriptomic tuberculosis (TB) signature, RISK11, and effects of TB preventative therapy (TPT) and respiratory organisms on RISK1...

We tested performance of host-blood transcriptomic tuberculosis (TB) signatures for active case-finding. Among 20,207 HIV-uninfected and 963 HIV-infected adults screened; 2,923 and 861 were enrolled from five South African communities. Eight signatures were measured by microfluidic RT-qPCR and participants were microbiologically-investigated for pulmonary TB at baseline, and actively surveilled for incident disease through 15 months. Diagnostic AUCs for 61 HIV-uninfected (weighted-prevalence 1.1%) and 10 HIV-infected (prevalence 1.2%) prevalent TB cases for the 8 signatures were 0.63–0.79 and 0.65–0.88, respectively. Thereafter, 24 HIV-uninfected and 9 HIV-infected participants progressed to incident TB (1.1 and 1.0 per 100 person-years, respectively). Prognostic AUCs through 15-months follow-up were 0.49–0.66 and 0.54–0.81, respectively. Prognostic performance for incident TB occurring within 6-12 months in HIV-negative participants was higher for all signatures. None of the signatures met WHO Target Product Profile criteria for a triage test to diagnose asymptomatic TB; most signatures met the criteria for symptomatic TB. Prognostic accuracy of most signatures for incident TB within six months of testing met the criteria for an incipient TB test.

Key Points MAIT cells comprise half the CD8 T cell IFN-γ response to BCG in blood. Frequencies of MAIT cells were not sustainably modulated by BCG vaccination. Innate cytokines mediate BCG-induced MAIT cell responses in whole blood., Tuberculosis (TB) is the leading cause of mortality from a single infectious agent, Mycobacterium tuberculosis. Relevant immune targets of the partially efficacious TB vaccine bacille Calmette–Guérin (BCG) remain poorly defined. Mucosal-associated invariant T (MAIT) cells are MHC-related protein 1 (MR1)–restricted T cells, which are reactive against M. tuberculosis, and underexplored as potential TB vaccine targets. We sought to determine whether BCG vaccination activated mycobacteria-specific MAIT cell responses in humans. We analyzed whole blood samples from M. tuberculosis–infected South African adults who were revaccinated with BCG after a six-month course of isoniazid preventative therapy. In vitro BCG stimulation potently induced IFN-γ expression by phenotypic (CD8+CD26+CD161+) MAIT cells, which constituted the majority (75%) of BCG-reactive IFN-γ–producing CD8+ T cells. BCG revaccination transiently expanded peripheral blood frequencies of BCG-reactive IFN-γ+ MAIT cells, which returned to baseline frequencies a year following vaccination. In another cohort of healthy adults who received BCG at birth, 53% of mycobacteria-reactive–activated CD8 T cells expressed CDR3α TCRs, previously reported as MAIT TCRs, expressing the canonical TRAV1-2-TRAJ33 MAIT TCRα rearrangement. CD26 and CD161 coexpression correlated with TRAV1-2+CD161+ phenotype more accurately in CD8+ than CD4−CD8− MAIT cells. Interestingly, BCG-induced IFN-γ expression by MAIT cells in vitro was mediated by the innate cytokines IL-12 and IL-18 more than MR1-induced TCR signaling, suggesting TCR-independent activation. Collectively, the data suggest that activation of blood MAIT cells by innate inflammatory cytokines is a major mechanism of responsiveness to vaccination with whole cell vaccines against TB or in vitro stimulation with mycobacteria (Clinical trial registration: NCT01119521).

Microbial culture is the gold standard for determining the effectiveness of tuberculosis treatment. End-of-treatment (EOT) 18F-FDG PET/CT findings are variable among patients with negative microbial culture results after completing a standard regimen of antituberculous treatment (ATT), with some patients having a complete metabolic response to treatment whereas others have residual metabolic activity (RMA). We herein determine the impact of findings on EOT 18F-FDG PET/CT on tuberculosis relapse in patients treated with a standard regimen of ATT for drug-sensitive pulmonary tuberculosis (DS-PTB). Methods: Patients who completed a standard regimen of ATT for DS-PTB and were declared cured based on a negative clinical and bacteriologic examination were prospectively recruited to undergo EOT 18F-FDG PET/CT. Images were assessed for the presence of RMA. Patients were subsequently followed up for 6 mo looking for symptoms of tuberculosis relapse. When new symptoms developed, relapse was confirmed with bacteriologic testing. Repeat 18F-FDG PET/CT was done in patients who relapsed. Results: Fifty-three patients were included (mean age, 37.81 ± 11.29 y), with 62% being male and 75% HIV-infected. RMA was demonstrated in 33 patients (RMA group), whereas 20 patients had a complete metabolic response to ATT (non-RMA group). There was a higher prevalence of lung cavitation in the RMA group (P = 0.035). The groups did not significantly differ in age, sex, presence of HIV infection, body mass index, or hemoglobin level (P > 0.05). On follow-up, no patients in the non-RMA group developed tuberculosis relapse. Three patients in the RMA group developed relapse. All patients who developed tuberculosis relapse had bilateral disease with lung cavitation. Conclusion: A negative EOT 18F-FDG PET/CT result is protective against tuberculosis relapse. Nine percent of patients with RMA after ATT may experience tuberculosis relapse within 6 mo of completing ATT. Bilateral disease with lung cavitation is prevalent among patients with tuberculosis relapse.

Global tuberculosis (TB) control requires effective vaccines in TB-endemic countries, where most adults are infected with Mycobacterium tuberculosis (M.tb).We sought to define optimal dose and schedule of H56:IC31, an experimental TB vaccine comprising Ag85B, ESAT-6, and Rv2660c, for M.tb-infected and M.tb-uninfected adults.We enrolled 98 healthy, HIV-uninfected, bacillus Calmette-Guérin-vaccinated, South African adults. M.tb infection was defined by QuantiFERON-TB (QFT) assay. QFT-negative participants received two vaccinations of different concentrations of H56 in 500 nmol of IC31 to enable dose selection for further vaccine development. Subsequently, QFT-positive and QFT-negative participants were randomized to receive two or three vaccinations to compare potential schedules. Participants were followed for safety and immunogenicity for 292 days.H56:IC31 showed acceptable reactogenicity profiles irrespective of dose, number of vaccinations, or M.tb infection. No vaccine-related severe or serious adverse events were observed. The three H56 concentrations tested induced equivalent frequencies and functional profiles of antigen-specific CD4 T cells. ESAT-6 was only immunogenic in QFT-negative participants who received three vaccinations.Two or three H56:IC31 vaccinations at the lowest dose induced durable antigen-specific CD4 T-cell responses with acceptable safety and tolerability profiles in M.tb-infected and M.tb-uninfected adults. Additional studies should validate applicability of vaccine doses and regimens to both QFT-positive and QFT-negative individuals. Clinical trial registered with www.clinicaltrials.gov (NCT01865487).

RationaleThe major human genes regulating M. tuberculosis (Mtb)-induced immune responses and tuberculosis (TB) susceptibility are poorly understood. Although IL-12 and IL-10 are critical for TB pathogenesis, the genetic factors that regulate their expression are unknown. CNBP, REL, and BHLHE40 are master regulators of IL-12 and IL-10 signaling.ObjectivesTo determine whether common human genetic variation in CNBP, REL and BHLHE40 is associated with IL-12 and IL-10 expression, adaptive immune responses to mycobacteria, and susceptibility to TB.Methods and Main MeasurementsWe characterized the association between common variants in CNBP, REL, and BHLHE40 and innate immune responses in dendritic cells and monocyte-derived macrophages (MDM), BCG-specific T cell responses, and susceptibility to pediatric and adult TB.ResultsSNP BHLHE40 rs4496464 was associated with increased BHLHE40 expression in MDMs and increased IL-10 from both peripheral blood dendritic cells and MDMs after LPS and TB whole cell lysate stimulation. SNP BHLHE40 rs11130215, in linkage disequilibrium with rs4496464, was associated with increased BCG-specific IL2+CD4+ T cell responses and decreased risk for pediatric TB in South Africa. SNPs REL rs842634 and CNBP rs11709852 were associated with increased IL-12 production from dendritic cells, and SNP REL rs842618, in linkage disequilibrium with rs842634, was associated with increased risk for TB meningitis.ConclusionsGenetic variation in CNBP, REL, and BHLHE40 is associated with IL-12 and IL-10 cytokine response and TB clinical outcomes. Common human genetic regulation of well-defined intermediate cellular traits provides insights into mechanisms of TB pathogenesis.

The risk of progression from Mycobacterium tuberculosis (M.tb) infection to active tuberculosis (TB) disease varies markedly with age. TB disease is significantly less likely in pre-adolescent children above 4 years of age than in very young children or post-pubescent adolescents and young adults. We hypothesized that pro-inflammatory responses to M.tb in pre-adolescent children are either less pronounced or more regulated, than in young adults. Inflammatory and antimicrobial mediators, measured by microfluidic RT-qPCR and protein bead arrays, or by analyzing published microarray data from TB patients and controls, were compared in pre-adolescent children and adults. Multivariate analysis revealed that M.tb-uninfected 8-year-old children had lower levels of myeloid-associated pro-inflammatory mediators than uninfected 18-year-old young adults. Relative to uninfected children, those with M.tb-infection had higher levels of similar myeloid inflammatory responses. These inflammatory mediators were also expressed after in vitro stimulation of whole blood from uninfected children with live M.tb. Our findings suggest that myeloid inflammation is intrinsically lower in pre-pubescent children than in young adults. The lower or more regulated pro-inflammatory responses may play a role in the lower risk of TB disease in this age group.

BackgroundRecent Mycobacterium tuberculosis (M.tb) infection is associated with a higher risk of progression to tuberculosis disease, compared to persistent infection after remote exposure. However, current immunodiagnostic tools fail to distinguish between recent and remote infection. We aimed to characterise the immunobiology associated with acquisition of M.tb infection and identify a biomarker that can distinguish recent from remote infection.MethodsHealthy South African adolescents were serially tested with QuantiFERON-TB Gold to define recent (QuantiFERON-TB conversion 1.5 year) infection. We characterized M.tb-specific CD4 T cell functional (IFN-γ, TNF, IL-2, CD107, CD154), memory (CD45RA, CCR7, CD27, KLRG-1) and activation (HLA-DR) profiles by flow cytometry after CFP-10/ESAT-6 peptide pool or M.tb lysate stimulation. We then assessed the diagnostic performance of immune profiles that were differentially expressed between individuals with recent or persistent QuantiFERON-TB+.FindingsCFP-10/ESAT-6-specific CD4 T cell activation but not functional or memory phenotypes distinguished between individuals with recent and persistent QuantiFERON-TB+. In response to M.tb lysate, recent QuantiFERON-TB+ individuals had lower proportions of highly differentiated IFN-γ+TNF+ CD4 T cells expressing a KLRG-1+ effector phenotype and higher proportions of early differentiated IFN-γ-TNF+IL-2+ and activated CD4 T cells compared to persistent QuantiFERON-TB+ individuals. Among all differentially expressed T cell features CFP-10/ESAT-6-specific CD4 T cell activation was the best performing diagnostic biomarker of recent infection.InterpretationRecent M.tb infection is associated with highly activated and moderately differentiated functional M.tb-specific T cell subsets, that can be used as biomarkers to distinguish between recent and remote infection.

Rationale: Current diagnostic tests fail to identify individuals at higher risk of progression to tuberculosis disease, such as those with recent Mycobacterium tuberculosis infection, who should be...

Infants are highly susceptible to disease caused by infection with intracellular pathogens, such as Mycobacterium tuberculosis. The Bacille Calmette-Guerin (BCG) vaccine is usually administered at birth to protect against severe forms of tuberculosis in children. BCG also has non-specific protective effects against heterologous infections, thought to be mediated by enhanced innate cell functions. We aimed to determine whether newborn BCG vaccination modulates myeloid and NK cell responses to mycobacteria. We enrolled 130 South African infants in whom BCG vaccination was either administered at birth or delayed to 6 or 10 weeks of age. CD4 T, myeloid and NK cell responses to whole cell mycobacteria were measured by flow cytometry. Levels of cytokines secreted upon whole blood stimulation with BCG were measured by multiplex bead array. Newborn BCG vaccination was associated with significantly higher frequencies of BCG-reactive, cytokine-expressing CD4+ T cells and IFNγ-expressing NK cells, compared with unvaccinated infants at 5-weeks and 9-weeks of age. However, cytokine-expressing CD33+ myeloid cells were not different between vaccinated and unvaccinated infants. Induction of BCG-reactive IFNγ-expressing NK cells was not associated with enhanced NK cell maturation, differentiation or cytokine receptor expression. Although levels of secreted cytokines were not different in vaccinated and unvaccinated infants, BCG-reactive NK cell responses correlated directly with levels of IL-2 and IFNγ, and the innate pro-inflammatory cytokines IL-6, IL-1β and TNF in BCG vaccinated infants only. Our data show that BCG-reactive IFNγ-expressing NK cells are strongly induced by BCG vaccination in infants and are likely amplified through by-stander cytokine-mediated activation. Further studies in infants are needed to improve our understanding of the possible role BCG-induced NK cell responses may play in mediating protection against tuberculosis and other infectious diseases. Funding Statement: NIH (R01AI087915), European and Developing Countries Clinical Trials Partnership (EDCTP, TA.2011.40200.010), South African National Research Foundation (MSc and PhD fellowships to MM). Declaration of Interests: No competing interests. Ethics Approval Statement: Parents or legal guardians provided written, informed consent before enrolment in the study. The Human Research Ethics Committee at the University of Cape Town approved protocols for infants vaccinated at birth (REF: 126/2006) and infants who had delayed BCG vaccination (REF: 177/2011). Good Clinical Practice procedures and the World Medical Association Declaration of Helsinki guidelines were adhered to.

Summary Background Targeted preventive therapy for individuals at highest risk of incident tuberculosis might impact the epidemic by interrupting transmission. We tested performance of a transcriptomic signature of tuberculosis (RISK11) and efficacy of signature-guided preventive therapy in parallel, using a hybrid three-group study design. Methods Adult volunteers aged 18–59 years were recruited at five geographically distinct communities in South Africa. Whole blood was sampled for RISK11 by quantitative RT-PCR assay from eligible volunteers without HIV, recent previous tuberculosis (ie

Background Adolescents in the Western Cape Province of South Africa had high force of Mycobacterium tuberculosis (MTB) infection (14% per annum) and high TB incidence (710 per 100,000 person-years) in 2005. We describe subsequent temporal changes in adolescent TB disease notification rates for the decade 2005-2015. Method We conducted an analysis of patient-level adolescent (age 10-19 years) TB disease data, obtained from an electronic TB register in the Breede Valley sub-district, Western Cape Province, South Africa, for 2005-2015. Numerators were annual TB notifications (HIV-related and HIV-unrelated); denominators were mid-year population estimates. Period averages of TB rates were obtained using time series modeling. Temporal trends in TB rates were explored using the Mann-Kendall test. Findings The average adolescent TB disease notification rate was 477 per 100,000 for all TB patients (all-TB) and 361 per 100,000 for microbiologically-confirmed patients. The adolescent all-TB rate declined by 45% from 662 to 361 per 100,000 and the microbiologically-confirmed TB rate by 38% from 492 to 305 per 100,000 between 2005-2015, driven mainly by rapid decreases for the period 2005-2009. There was a statistically significant negative temporal trend in both all-TB (per 100,000) (declined by 48%; from 662 to 343; p = 0·028) and microbiologically confirmed TB (per 100,000) (declined by 49%; from 492 to 252; p = 0·027) for 2005-2009, which was not observed for the period 2009-2015 (rose 5%; from 343 to 361; p = 0·764 and rose 21%; from 252 to 305; p = 1·000, respectively). Interpretation We observed an encouraging fall in adolescent TB disease rates between 2005-2009 with a subsequent plateau during 2010-2015, suggesting that additional interventions are needed to sustain initial advances in TB control.

BackgroundProvision of tuberculosis preventive treatment (TPT) to individuals withMycobacterium tuberculosis(M.tb) infection (TBI) is a key strategy to reduce the global tuberculosis burden. Tuberculosis risk is significantly higher after recent compared to remote TBI. We aimed to define a blood-based biomarker, measured with a simple flow cytometry assay, to stratify different stages of TBI to infer risk of disease.MethodsHealthy adolescents were serially tested with QuantiFERON-TB Gold (QFT) to define recent (QFT conversion 1 year) TBI. M.tb-specific T cells were defined as IFN-g+TNF+CD3+ cells upon CFP-10/ESAT-6 or M.tb lysate stimulation. ΔHLA-DR median fluorescence intensity (MFI) was defined as the difference in HLA-DR expression between M.tb-specific and total T cells. Biomarker performance was assessed by blinded prediction in untouched test cohorts with recentversusremote TBI or tuberculosis disease, and unblinded analysis of asymptomatic adolescents with TBI who remained healthy (non-progressors) or who progressed to microbiologically-confirmed disease (progressors).FindingsIn the test cohorts, frequencies of M.tb-specific T cells differentiated between QFT- (n=25) and QFT+ (n=47) individuals [area under the ROC curve (AUCROC): 0.94; 95%CI: 0.87-1.00]. ΔHLA-DR MFI significantly discriminated between recent (n=20) and remote (n=22) TBI (AUCROC 0.91; 95%CI: 0.83-1.00); remote TBI and newly diagnosed tuberculosis (n=19; AUCROC 0.99; 95%CI: 0.96-1.00); and between tuberculosis progressors (n=22) and non-progressors (n=34; AUCROC 0.75, 95%CI: 0.63-0.87).InterpretationThe ΔHLA-DR MFI biomarker can identify individuals with recent TBI and those with disease progression, allowing targeted provision of TPT to those at highest risk of tuberculosis.

BACKGROUND: Tuberculosis incidence varies seasonally in many settings. However, the role of seasonal variation in reactivation vs. transmission is unclear.METHODS: We reviewed data on TB notifications in Cape Town, South Africa, from 1903 to 2017 (exclusive of 1995–2002, which were unavailable). Data from 2003 onward were stratified by HIV status, age and notification status (new vs. retreatment). We performed seasonal decomposition and time-dependent spectral analysis using wavelets to assess periodicity over time. We estimated monthly peak-to-peak seasonal amplitude of notifications as a percentage of the annual notification rate.RESULTS: A seasonal trend was intermittently detected between 1904 and 1994, particularly during periods of high notification rates, but was consistently and strongly evident between 2003 and 2017, with peaks in September through November, following winter. Among young children, a second, higher seasonal peak was observed in March. Seasonal variation was greater in children (CONCLUSIONS: Stronger seasonal effects were seen in children, in whom progression following recent infection is known to be the predominant driver of disease. These findings may support increased transmission in the winter as an important driver of TB in Cape Town.

Introduction Respiratory pathogens such as influenza viruses may play an influential role in the pathogenesis of TB by negatively affecting immunity against Mycobacterium tuberculosis (MTB) We discovered and validated a transcriptomic signature of risk (SOR), based on mRNA expression of 11 IFN stimulated genes (ISG), which prospectively differentiates between incident TB cases and healthy controls The SOR score is computed from expression abundance of multiple ISG transcript pairs in peripheral blood, whereby each pair functions as a ?vote? for or against TB risk We aimed to identify respiratory pathogens other than MTB that might also associate with this SOR score and test whether the SOR score differentiates between individuals with and without respiratory pathogens Methods We conducted a nested cross-sectional study of the upper respiratory tract microbiome Upon consent, participants were consecutively enrolled into the study and provided one nasopharyngeal, one oropharyngeal and a PAXgene blood sample Host blood SOR scores were computed from Ct values for each of the 11 genes, measured by microfluidic qRT-PCR We used multiplex real-time PCR to detect 33 pathogens including bacteria, viruses and fungi in the nasopharyngeal and oropharyngeal samples Multivariate linear regression was used to identify pathogens associated with, and estimate their effect on, the SOR score Wilcoxon rank sum tests and receiver-operating-characteristic (ROC) curves were used to differentiate participants with and without respiratory pathogens Results 1,000 HIV-negative volunteers aged between 18 and 60 years were enrolled 13 viral and nine bacterial pathogens were detected Overall prevalence of respiratory pathogens was 43%: 4% were viruses only, 35 8% bacteria only, and 3 2% were a combination of viruses and bacteria Influenza C, rhinoviruses, coronavirus OC43, adenoviruses, and mycoplasma pneumoniae were significantly associated (Table 1) with a high SOR score In ROC curve analysis the SOR score differentiated participants as follows;virus vs no-pathogen (area under the curve;AUC) AUC=0 72, 95% CI: 0 63-0 81, virus vs bacteria AUC=0 72, 95% CI: 0 63-0 81, bacteria vs no-pathogen AUC=0 51, 95% CI: 0 48-0 55 (no difference) Participants with either viruses only or both viruses and bacteria had significantly higher (P=0 001) SOR scores (median 47% and 43%, respectively) compared to participants without pathogens (median 14%) or participants with bacteria only (median 13%) Conclusion Participants with upper respiratory tract viral colonization or infection had elevated SOR scores, suggesting induction of interferon signalling Infection or colonization with respiratory viruses is likely to result in false positive results for other transcriptomic signatures of tuberculosis based on ISGs (Table Presented)

Summary Background Blood transcriptional signatures are candidates for non-sputum triage or confirmatory tests of tuberculosis. Prospective head-to-head comparisons of their diagnostic accuracy in real-world settings are necessary to assess their clinical use. We aimed to compare the diagnostic accuracy of candidate transcriptional signatures identified by systematic review, in a setting with a high burden of tuberculosis and HIV. Methods We did a prospective observational study nested within a diagnostic accuracy study of sputum Xpert MTB/RIF (Xpert) and Xpert MTB/RIF Ultra (Ultra) tests for pulmonary tuberculosis. We recruited consecutive symptomatic adults aged 18 years or older self-presenting to a tuberculosis clinic in Cape Town, South Africa. Participants provided blood for RNA sequencing, and sputum samples for liquid culture and molecular testing using Xpert and Ultra. We assessed the diagnostic accuracy of candidate blood transcriptional signatures for active tuberculosis (including those intended to distinguish active tuberculosis from other diseases) identified by systematic review, compared with culture or Xpert MTB/RIF positivity as the standard reference. In our primary analysis, patients with tuberculosis were defined as those with either a positive liquid culture or Xpert result. Patients with missing blood RNA or sputum results were excluded. Our primary objective was to benchmark the diagnostic accuracy of candidate transcriptional signatures against the WHO target product profile (TPP) for a tuberculosis triage test. Findings Between Feb 12, 2016, and July 18, 2017, we obtained paired sputum and RNA sequencing data from 181 participants, 54 (30%) of whom had confirmed pulmonary tuberculosis. Of 27 eligible signatures identified by systematic review, four achieved the highest diagnostic accuracy with similar area under the receiver operating characteristic curves (Sweeney3: 90·6% [95% CI 85·6–95·6]; Kaforou25: 86·9% [80·9–92·9]; Roe3: 86·9% [80·3–93·5]; and BATF2: 86·8% [80·6–93·1]), independent of age, sex, HIV status, previous tuberculosis, or sputum smear result. At test thresholds that gave 70% specificity (the minimum WHO TPP specificity for a triage test), these four signatures achieved sensitivities between 83·3% (95% CI 71·3–91·0) and 90·7% (80·1–96·0). No signature met the optimum criteria, of 95% sensitivity and 80% specificity proposed by WHO for a triage test, or the minimum criteria (of 65% sensitivity and 98% specificity) for a confirmatory test, but all four correctly identified Ultra-positive, culture-negative patients. Interpretation Selected blood transcriptional signatures met the minimum WHO benchmarks for a tuberculosis triage test but not for a confirmatory test. Further development of the signatures is warranted to investigate their possible effects on clinical and health economic outcomes as part of a triage strategy, or when used as add-on confirmatory test in conjunction with the highly sensitive Ultra test for Mycobacterium tuberculosis DNA. Funding Royal Society Newton Advanced Fellowship, Wellcome Trust, National Institute of Health Research, and UK Medical Research Council.

Mycobacterium tuberculosis (Mtb) kills more people worldwide than any single infectious pathogen, yet the only vaccine licensed against tuberculosis, Bacille Calmette Guerin (BCG) is approaching its centenary. Two recent advances in clinical tuberculosis vaccine development have invigorated the field. BCG revaccination of interferon-gamma release assay (IGRA) negative adolescents provided 45% protection against sustained Mtb infection defined by IGRA conversion; and the protein-subunit vaccine M72/AS01 E provided 50% protection against progression from Mtb infection to tuberculosis disease in IGRA-positive adults. These findings provide encouraging evidence for pre-exposure and post-exposure approaches to vaccination against tuberculosis, both of which may be necessary to rapidly interrupt the cycle of Mtb transmission and sustain long-term impact on global tuberculosis control. New trials are needed to demonstrate efficacy of M72/AS01 E with greater precision, in a wider age range, in diverse epidemic settings, and in populations that include Mtb-uninfected and HIV-infected persons. Modeling the impact of mass campaigns with M72/AS01 E and other fast-follower vaccine candidates will be crucial to make the use case and demonstrate public health value for TB endemic countries. The size and scope of the next generation of efficacy trials, and the need to expand and accelerate the existing clinical development pipeline, will require public and private consortium funding and concerted political will.

Background: We tested diagnostic and prognostic performance of a host blood transcriptomic signature of tuberculosis (RISK11) for screening of people living with HIV (PLHIV) in a prospective, community-based cohort. Methods: Ambulant adult volunteers living with HIV were enrolled at five South African sites. RISK11 status was assessed at baseline by real-time PCR. Participants and study staff were blinded to the result. Participants underwent active surveillance for microbiologically-confirmed tuberculosis from enrolment through 15 months. The primary outcomes were prevalence and cumulative incidence of two-sputum-sample positive tuberculosis in RISK11+ versus RISK11- participants. Findings: Among 820 participants with valid RISK11 results, eight (1%) tuberculosis cases were identified at baseline. Risk of prevalent tuberculosis was 13·1-fold (95%CI 2·1-81·6) greater in RISK11+ than RISK11- participants, with tuberculosis prevalence of 2·5% and 0·2%, respectively. RISK11 had diagnostic area under the receiver-operating-characteristic curve (AUC) 88·2%; sensitivity 87·5% and specificity 65·8% at the pre-defined threshold (60%).Thereafter, eight tuberculosis cases were identified through median 15 months follow-up. Tuberculosis incidence was 2·5 vs 0·2 per 100 person-years in RISK11+ compared to RISK11- participants with cumulative incidence ratio 16·0 (95%CI 2·0-129·5); AUC 80·0%; sensitivity 88·6% and specificity 68·9%. By comparison, QuantiFERON TB Gold-Plus (QFT) had a cumulative incidence ratio of 2·0 (95%CI 0·5-8·4); AUC 70·8%; sensitivity 62·1% and specificity 56·2%. Interpretation: RISK11 identified prevalent tuberculosis and predicted risk of progression to incident tuberculosis within 15 months in ambulant PLHIV. Performance approached the World Health Organization Target Product Profile benchmarks for screening and prognostic tests for tuberculosis. QFT performance fell short of the prognostic benchmark. Funding Statement: The study was funded by the Bill & Melinda Gates Foundation (BMGF) (OPP1151915) and by the Strategic Health Innovation Partnerships Unit of the South African Medical Research Council with funds received from the South African Department of Science and Technology. The BMGF contributed to the study design. The regulatory sponsor was the University of Cape Town. Declaration of Interests: AP-N, GW, GC, TJS, and MH report grants from the Bill & Melinda Gates Foundation, during the conduct of the study; AP-N and GW report grants from the South African Medical Research Council, during the conduct of the study; GW and TJS report grants from the South African National Research Foundation, during the conduct of the study. In addition, AP-N and TJS have patents of the RISK11 and RISK6 signatures pending; GW has a patent “TB diagnostic markers” (PCT/IB2013/054377) issued and a patent “Method for diagnosing TB” (PCT/IB2017/052142) pending. The remaining authors have no competing interests to declare. Ethics Approval Statement: The study protocol (Supplement) was approved by the Institutional Human Ethics Committees of each participating site. All participants provided written informed consent in their language of choice.

Oral swabs are emerging as a non-invasive sample type for diagnosing infectious diseases including Ebola, tuberculosis (TB), and COVID-19. To assure proper sample collection, sample adequacy controls (SACs) are needed that detect substances indicative of samples collected within the oral cavity. This study evaluated two candidate SACs for this purpose. One detected representative oral microbiota (Streptococcus species DNA) and the other, human cells (human mitochondrial DNA, mtDNA). Quantitative PCR (qPCR) assays for the two target cell types were applied to buccal swabs (representing samples collected within the oral cavity) and hand swabs (representing improperly collected samples) obtained from 51 healthy U.S. volunteers. Quantification cycle (Cq) cutoffs that maximized Youden’s index were established for each assay. The streptococcal target at a Cq cutoff of ≤34.9 had 99.0% sensitivity and specificity for oral swab samples, whereas human mtDNA perfectly distinguished between hand and mouth swabs with a Cq cutoff of 31.3. The human mtDNA test was then applied to buccal, tongue, and gum swabs that had previously been collected from TB patients and controls in South Africa, along with “air swabs” collected as negative controls (total N = 292 swabs from 71 subjects). Of these swabs, 287/292 (98%) exhibited the expected Cq values. In a paired analysis the three oral sites yielded indistinguishable amounts of human mtDNA, however PurFlock™ swabs collected slightly more human mtDNA than did OmniSwabs™ (p = 0.012). The results indicate that quantification of human mtDNA cannot distinguish swabs collected from different sites within the mouth. However, it can reliably distinguish oral swabs from swabs that were not used orally., which makes it a useful SAC for oral swab-based diagnosis.

IntroductionCurrent tuberculosis triage and predictive tools offer poor accuracy and are ineffective for detecting asymptomatic disease in people living with HIV (PLHIV). Host tuberculosis transcriptomic biomarkers hold promise for diagnosing prevalent and predicting progression to incident tuberculosis and guiding further investigation, preventive therapy and follow-up. We aim to conduct a systematic review of performance of transcriptomic signatures of tuberculosis in PLHIV.Methods and analysisWe will search MEDLINE (PubMed), WOS Core Collection, Biological Abstracts, and SciELO Citation Index (Web of Science), Africa-Wide Information and General Science Abstracts (EBSCOhost), Scopus, and Cochrane Central Register of Controlled Trials databases for articles published in English between 1990 and 2020. Case–control, cross-sectional, cohort and randomised controlled studies evaluating performance of diagnostic and prognostic host-response transcriptomic signatures in PLHIV of all ages and settings will be included. Eligible studies will include PLHIV in signature test or validation cohorts, and use microbiological, clinical, or composite reference standards for pulmonary or extrapulmonary tuberculosis diagnosis. Study quality will be evaluated using the ‘Quality Assessment of Diagnostic Accuracy Studies-2’ tool and cumulative review evidence assessed using the ‘Grading of Recommendations Assessment, Development and Evaluation’ approach. Study selection, quality appraisal and data extraction will be performed independently by two reviewers. Study, cohort and signature characteristics of included studies will be tabulated, and a narrative synthesis of findings presented. Primary outcomes of interest, biomarker sensitivity and specificity with estimate precision, will be summarised in forest plots. Expected heterogeneity in signature characteristics, study settings, and study designs precludes meta-analysis and pooling of results. Review reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy Studies guidelines.Ethics and disseminationFormal ethics approval is not required as primary human participant data will not be collected. Results will be disseminated through peer-reviewed publication and conference presentation.PROSPERO registration numberCRD42021224155.

Summary Background A therapeutic vaccine that prevents recurrent tuberculosis would be a major advance in the development of shorter treatment regimens. We aimed to assess the safety and immunogenicity of the ID93 + GLA-SE vaccine at various doses and injection schedules in patients with previously treated tuberculosis. Methods This randomised, double-blind, placebo-controlled, phase 2a trial was conducted at three clinical sites near Cape Town, South Africa. Patients were recruited at local clinics after receiving 4 months of tuberculosis treatment, and screened for eligibility after providing written informed consent. Participants were aged 18–60 years, BCG-vaccinated, HIV-uninfected, and diagnosed with drug-sensitive pulmonary tuberculosis. Eligible patients had completed standard treatment for pulmonary tuberculosis in the past 28 days. Participants were enrolled after completing standard treatment and randomly assigned sequentially to receive vaccine or placebo in three cohorts: 2 μg intramuscular ID93 + 2 μg GLA-SE on days 0 and 56 (cohort 1); 10 μg ID93 + 2 μg GLA-SE on days 0 and 56 (cohort 2); 2 μg ID93 + 5 μg GLA-SE on days 0 and 56 and placebo on day 28 (cohort 3); 2 μg ID93 + 5 μg GLA-SE on days 0, 28, and 56 (cohort 3); or placebo on days 0 and 56 (cohorts 1 and 2), with the placebo group for cohort 3 receiving an additional injection on day 28. Randomisation was in a ratio of 3:1 for ID93 + GLA-SE and saline placebo in cohorts 1 and 2, and in a ratio of 3:3:1 for (2 ×) ID93 + GLA-SE, (3 ×) ID93 + GLA-SE, and placebo in cohort 3. The primary outcomes were safety and immunogenicity (vaccine-specific antibody response and T-cell response). For the safety outcome, participants were observed for 30 min after each injection, injection site reactions and systemic adverse events were monitored until day 84, and serious adverse events and adverse events of special interest were monitored for 6 months after the last injection. Vaccine-specific antibody responses were measured by serum ELISA, and T-cell responses after stimulation with vaccine antigens were measured in cryopreserved peripheral blood mononuclear cells specimens using intracellular cytokine staining followed by flow cytometry. This study is registered with ClinicalTrials.gov , number NCT02465216 . Findings Between June 17, 2015, and May 30, 2016, we assessed 177 patients for inclusion. 61 eligible patients were randomly assigned to receive: saline placebo (n=5) or (2 ×) 2 μg ID93 + 2 μg GLA-SE (n=15) on days 0 and 56 (cohort 1); saline placebo (n=2) or (2 ×) 10 μg ID93 + 2 μg GLA-SE (n=5) on days 0 and 56 (cohort 2); saline placebo (n=5) on days 0, 28 and 56, or 2 μg ID93 + 5 μg GLA-SE (n=15) on days 0 and 56 and placebo injection on day 28, or (3 ×) 2 μg ID93 + 5 μg GLA-SE (n=14) on days 0, 28, and 56 (cohort 3). ID93 + GLA-SE induced robust and durable antibody responses and specific, polyfunctional CD4 T-cell responses to vaccine antigens. Two injections of the 2 μg ID93 + 5 μg GLA-SE dose induced antigen-specific IgG and CD4 T-cell responses that were significantly higher than those with placebo and persisted for the 6-month study duration. Mild to moderate injection site pain was reported after vaccination across all dose combinations, and induration and erythema in patients given 2 μg ID93 + 5 μg GLA-SE in two or three doses. One participant had grade 3 erythema and induration at the injection site. No vaccine-related serious adverse events were observed. Interpretation Vaccination with ID93 + GLA-SE was safe and immunogenic for all tested regimens. These data support further evaluation of ID93 + GLA-SE in therapeutic vaccination strategies to improve tuberculosis treatment outcomes. Funding Wellcome Trust (102028/Z/13/Z).

Improved tuberculosis diagnostics and tools for monitoring treatment response are urgently needed. We developed a robust and simple, PCR-based host-blood transcriptomic signature, RISK6, for multiple applications: identifying individuals at risk of incident disease, as a screening test for subclinical or clinical tuberculosis, and for monitoring tuberculosis treatment. RISK6 utility was validated by blind prediction using quantitative real-time (qRT) PCR in seven independent cohorts.Prognostic performance significantly exceeded that of previous signatures discovered in the same cohort. Performance for diagnosing subclinical and clinical disease in HIV-uninfected and HIV-infected persons, assessed by area under the receiver-operating characteristic curve, exceeded 85%. As a screening test for tuberculosis, the sensitivity at 90% specificity met or approached the benchmarks set out in World Health Organization target product profiles for non-sputum-based tests. RISK6 scores correlated with lung immunopathology activity, measured by positron emission tomography, and tracked treatment response, demonstrating utility as treatment response biomarker, while predicting treatment failure prior to treatment initiation. Performance of the test in capillary blood samples collected by finger-prick was noninferior to venous blood collected in PAXgene tubes. These results support incorporation of RISK6 into rapid, capillary blood-based point-of-care PCR devices for prospective assessment in field studies.

International audience; Tuberculosis (TB) remains one of the leading causes of mortality worldwide, and a lack of understanding of basic disease pathogenesis is hampering development of new vaccines and treatments. Multiple studies have previously established a role for type I interferon (IFN) in TB disease. Type I IFNs are critical immune mediators for host responses to viral infection, yet their specific influence in bacterial infection remains unclear. As IFN-stimulated genes (ISGs) can have both stimulatory and inhibitory effects on immune function, clarifying the role of type I interferon in TB remains an important question. The quantification of interferon proteins in the circulation of patients has been restricted until the recent development of digital ELISA. To test the hypothesis that patients with active TB disease have elevated circulating type I IFN we quantified plasma IFNα and β proteins with Simoa digital ELISA in patients with active disease and asymptomatic M. tuberculosis infection. Strikingly no differences were observed between these two groups, while plasma from acute influenza infection revealed significantly higher plasma levels of both IFNα and IFNβ proteins. These results suggest a discordance between ISG mRNA expression by blood leukocytes and circulating type I IFN in TB.

HIV-infected individuals are at high risk of tuberculosis disease and those with prior tuberculosis episodes are at even higher risk of disease recurrence. A non-sputum biomarker that identifies individuals at highest tuberculosis risk would allow targeted microbiological testing and appropriate treatment and also guide need for prolonged therapy. We determined the utility of a previously developed whole blood transcriptomic correlate of risk (COR) signature for (1) predicting incident recurrent tuberculosis, (2) tuberculosis diagnosis and (3) its potential utility for tuberculosis treatment monitoring in HIV-infected individuals. We retrieved cryopreserved blood specimens from three previously completed clinical studies and measured the COR signature by quantitative microfluidic real-time-PCR. The signature differentiated recurrent tuberculosis progressors from non-progressors within 3 months of diagnosis with an area under the Receiver-operating characteristic (ROC) curve (AUC) of 0.72 (95% confidence interval (CI), 0.58–0.85) amongst HIV-infected individuals on antiretroviral therapy (ART). Twenty-five of 43 progressors (58%) were asymptomatic at microbiological diagnosis and thus had subclinical disease. The signature showed excellent diagnostic discrimination between HIV-uninfected tuberculosis cases and controls (AUC 0.97; 95%CI 0.94–1). Performance was lower in HIV-infected individuals (AUC 0.83; 95%CI 0.81–0.96) and signature scores were directly associated with HIV viral loads. Tuberculosis treatment response in HIV-infected individuals on ART with a new recurrent tuberculosis diagnosis was also assessed. Signature scores decreased significantly during treatment. However, pre-treatment scores could not differentiate between those who became sputum negative before and after 2 months. Direct application of the unmodified blood transcriptomic COR signature detected subclinical and active tuberculosis by blind validation in HIV-infected individuals. However, prognostic performance for recurrent tuberculosis, and performance as diagnostic and as treatment monitoring tool in HIV-infected persons was inferior to published results from HIV-negative cohorts. Our results suggest that performance of transcriptomic signatures comprising interferon stimulated genes are negatively affected in HIV-infected individuals, especially in those with incompletely suppressed viral loads.

Immune activation is associated with increased risk of tuberculosis (TB) disease in infants. We performed a case-control analysis to identify drivers of immune activation and disease risk. Among 49 infants who developed TB disease over the first 2 years of life, and 129 healthy matched controls, we found the cytomegalovirus-stimulated (CMV-stimulated) IFN-γ response to be associated with CD8+ T cell activation (Spearman’s rho, P = 6 × 10–8). A CMV-specific IFN-γ response was also associated with increased risk of developing TB disease (conditional logistic regression; P = 0.043; OR, 2.2; 95% CI, 1.02–4.83) and shorter time to TB diagnosis (Log Rank Mantel-Cox, P = 0.037). CMV+ infants who developed TB disease had lower expression of NK cell–associated gene signatures and a lower frequency of CD3–CD4–CD8– lymphocytes. We identified transcriptional signatures predictive of TB disease risk among CMV ELISpot–positive (area under the receiver operating characteristic [AUROC], 0.98, accuracy, 92.57%) and –negative (AUROC, 0.9; accuracy, 79.3%) infants; the CMV– signature was validated in an independent infant study (AUROC, 0.71; accuracy, 63.9%). A 16-gene signature that previously identified adolescents at risk of developing TB disease did not accurately classify case and control infants in this study. Understanding the microbial drivers of T cell activation, such as CMV, could guide new strategies for prevention of TB disease in infants., A case control analysis identifies an association of cytomegalovirus (CMV) with increased risk of developing tuberculosis in infants.

Background: South African adolescents have a high force of Mycobacterium tuberculosis (MTB) infection, exceeding 10% per annum, which acts as a barometer of tuberculosis (TB) transmission. We described temporal changes in adolescent TB notification rates to evaluate impact of TB and HIV control measures and inform public health strategy. Method: We conducted a cross-sectional analysis of patient-level TB case data obtained from a regional health authority in Western Cape Province, South Africa, for the decade 2005–2015. Numerators were annual TB notifications (HIV-related and HIV-unrelated); denominators were mid-year population estimates from the national census, adjusted for population growth. Period averages of TB rates were obtained using Auto-Regressive Integrated Moving Average (ARIMA) time series modeling. The Agresti Coull method was used to derive confidence intervals for TB rates. Temporal trends in TB rates were explored using the Mann-Kendall test. Findings: The average adolescent TB notification rate was 477 (95% Confidence Interval (CI): 313–641) per 100,000 for all cases (all-TB) and 361 (CI: 280–441) per 100,000 for microbiologically confirmed cases. However, the adolescent all-TB rate fell by 45% from 662 to 361 per 100,000 (p=0·005) and the microbiologically-confirmed TB rate by 38% from 492 to 305 per 100,000 (p=0·008) between 2005-2015, driven mainly by rapid decreases for the period 2005–2009 (p=0·028 and p=0·027, respectively). Between 2005–2009, 21% (156/732) of adolescent TB notifications were HIV tested, 12% (19/156) of whom were HIV-positive. In the general population, the proportion of HIV-positive persons receiving antiretroviral therapy (ART) increased from

IntroductionOne-quarter of the global population, including the majority of adults in tuberculosis (TB) endemic countries, are estimated to beMycobacterium tuberculosis(MTB) infected. An estimated 10 million new TB cases occurred in 2017. One of the biggest challenges confronting TB control is the lack of accurate diagnosis and prediction of prevalent and incident TB disease, respectively. Several host blood transcriptomic messenger RNA (mRNA) signatures that reflect the host immune response following infection with MTB and progression to TB disease in different study populations have recently been published, but these TB biomarkers have not been systematically described. We will conduct a systematic review of the performance of host blood transcriptional signatures for TB diagnosis and prediction of progression to TB disease.Methods and analysisThis systematic review will involve conducting a comprehensive literature search of cohort, case–control, cross-sectional and randomised-controlled studies of the performance of host blood transcriptomic signatures for TB diagnosis and prediction of progression to TB disease. We will search Medline via PubMed, Scopus, Web of Science and EBSCO libraries, complemented by a search of bibliographies of selected articles for other relevant articles. The literature search will be restricted to studies published in English from 2005 to 2018 and conducted in HIV-uninfected adults and adolescents (≥12 years old). Forest plots and a narrative synthesis of the findings will be provided. The primary outcomes will be sensitivity, specificity, as well as true/false positives and true/false negatives. Heterogeneity resulting from differences in the design, composition and structure of individual signatures will preclude meta-analysis and pooling of results.Ethics and disseminationEthics approval is not required for this systematic review protocol. The results of this review will be disseminated through a peer-reviewed journal as well as conference presentations.PROSPERO registration numberCRD42017073817.

BACKGROUND: A nonsputum blood test capable of predicting progression of healthy individuals to active tuberculosis (TB) before clinical symptoms manifest would allow targeted treatment to curb transmission. We aimed to develop a proteomic biomarker of risk of TB progression for ultimate translation into a point-of-care diagnostic.METHODS AND FINDINGS: Proteomic TB risk signatures were discovered in a longitudinal cohort of 6,363 Mycobacterium tuberculosis-infected, HIV-negative South African adolescents aged 12-18 years (68% female) who participated in the Adolescent Cohort Study (ACS) between July 6, 2005 and April 23, 2007, through either active (every 6 months) or passive follow-up over 2 years. Forty-six individuals developed microbiologically confirmed TB disease within 2 years of follow-up and were selected as progressors; 106 nonprogressors, who remained healthy, were matched to progressors. Over 3,000 human proteins were quantified in plasma with a highly multiplexed proteomic assay (SOMAscan). Three hundred sixty-one proteins of differential abundance between progressors and nonprogressors were identified. A 5-protein signature, TB Risk Model 5 (TRM5), was discovered in the ACS training set and verified by blind prediction in the ACS test set. Poor performance on samples 13-24 months before TB diagnosis motivated discovery of a second 3-protein signature, 3-protein pair-ratio (3PR) developed using an orthogonal strategy on the full ACS subcohort. Prognostic performance of both signatures was validated in an independent cohort of 1,948 HIV-negative household TB contacts from The Gambia (aged 15-60 years, 66% female), longitudinally followed up for 2 years between March 5, 2007 and October 21, 2010, sampled at baseline, month 6, and month 18. Amongst these contacts, 34 individuals progressed to microbiologically confirmed TB disease and were included as progressors, and 115 nonprogressors were included as controls. Prognostic performance of the TRM5 signature in the ACS training set was excellent within 6 months of TB diagnosis (area under the receiver operating characteristic curve [AUC] 0.96 [95% confidence interval, 0.93-0.99]) and 6-12 months (AUC 0.76 [0.65-0.87]) before TB diagnosis. TRM5 validated with an AUC of 0.66 (0.56-0.75) within 1 year of TB diagnosis in the Gambian validation cohort. The 3PR signature yielded an AUC of 0.89 (0.84-0.95) within 6 months of TB diagnosis and 0.72 (0.64-0.81) 7-12 months before TB diagnosis in the entire South African discovery cohort and validated with an AUC of 0.65 (0.55-0.75) within 1 year of TB diagnosis in the Gambian validation cohort. Signature validation may have been limited by a systematic shift in signal magnitudes generated by differences between the validation assay when compared to the discovery assay. Further validation, especially in cohorts from non-African countries, is necessary to determine how generalizable signature performance is.CONCLUSIONS: Both proteomic TB risk signatures predicted progression to incident TB within a year of diagnosis. To our knowledge, these are the first validated prognostic proteomic signatures. Neither meet the minimum criteria as defined in the WHO Target Product Profile for a progression test. More work is required to develop such a test for practical identification of individuals for investigation of incipient, subclinical, or active TB disease for appropriate treatment and care.

Tuberculosis (TB) is caused byMycobacterium tuberculosis(Mtb) infection and is a major public health problem with an estimated 1.7 billion persons infected worldwide. Clinical challenges in TB include the lack of a blood-based test for active disease, and the absence of prognostic biomarkers for early treatment response. Current blood based tests, such as QuantiFERON-TB Gold (QFT), are based on an IFNγ readout followingMtbantigen stimulation. However, they do not distinguish active TB disease from asymptomaticMtbinfection. We hypothesized that the use of TruCulture, an improved immunomonitoring method for whole blood collection and immune stimulation, could improve the discrimination of active disease from latentMtbinfection. To test our hypothesis, we stimulated whole blood from active TB patients (before and after successful treatment), comparing them to asymptomatic latently infected individuals.Mtb-specific antigens (ESAT-6, CFP-10, TB7.7) and live bacillus Calmette-Guerin (BCG) were used for TruCulture stimulation conditions, with direct comparison to QFT. Protein analyses were performed on the culture supernatants using ELISA and Luminex multi-analyte profiling. TruCulture showed an ability to discriminate active TB cases from latent controls (p < 0.0001, AUC = 0.81, 95% CI: 0.69-0.93) as compared to QFT (p = 0.47 AUC = 0.56, 95% CI: 0.40-0.72), based on an IFNγ readout afterMtbantigen stimulation. The stratification of the two groups could be further improved by using theMtbAg/BCG IFNγ ratio response (p < 0.0001, AUC = 0.918, 95% CI: 0.84-0.98). We also identified additional cytokines that distinguished latent infection from TB disease; and show that the primary differences between the TruCulture and QFT systems were a result of higher levels of non-specific innate immune activation in QFT tubes, due to the lack of a buffering solution in the latter. We conclude that TruCulture offers a next-generation solution for whole blood stimulation and immunomonitoring with the possibility to discriminate active and latently infected persons.

Summary Background Infants are a key target population for new tuberculosis vaccines. We assessed the safety and immunogenicity of the live-attenuated Mycobacterium tuberculosis vaccine candidate MTBVAC in adults and infants in a region where transmission of tuberculosis is very high. Methods We did a randomised, double-blind, BCG-controlled, dose-escalation trial at the South African Tuberculosis Vaccine Initiative site near Cape Town, South Africa. Healthy adult community volunteers who were aged 18–50 years, had received BCG vaccination as infants, were HIV negative, had negative interferon-γ release assay (IGRA) results, and had no personal history of tuberculosis or current household contact with someone with tuberculosis were enrolled in a safety cohort. Infants born to HIV-negative women with no personal history of tuberculosis or current household contact with a person with tuberculosis and who were 96 h old or younger, generally healthy, and had not yet received routine BCG vaccination were enrolled in a separate infant cohort. Eligible adults were randomly assigned (1:1) to receive either BCG Vaccine SSI (5 × 105 colony forming units [CFU] of Danish strain 1331 in 0·1 mL diluent) or MTBVAC (5 × 105 CFU in 0·1 mL) intradermally in the deltoid region of the arm. After favourable review of 28-day reactogenicity and safety data in the adult cohort, infants were randomly assigned (1:3) to receive either BCG Vaccine SSI (2·5 × 105 CFU in 0·05 mL diluent) or MTBVAC in three sequential cohorts of increasing MTBVAC dose (2·5 × 103 CFU, 2·5 × 104 CFU, and 2·5 × 105 CFU in 0·05 mL) intradermally in the deltoid region of the arm. QuantiFERON-TB Gold In-Tube IGRA was done on days 180 and 360. For both randomisations, a pre-prepared block randomisation schedule was used. Participants (and their parents or guardians in the case of infant participants), investigators, and other clinical and laboratory staff were masked to intervention allocation. The primary outcomes, which were all measured in the infant cohort, were solicited and unsolicited local adverse events and serious adverse events until day 360; non-serious systemic adverse events until day 28 and vaccine-specific CD4 and CD8 T-cell responses on days 7, 28, 70, 180, and 360. Secondary outcomes measured in adults were local injection-site and systemic reactions and haematology and biochemistry at study day 7 and 28. Safety analyses and immunogenicity analyses were done in all participants who received a dose of vaccine. This trial is registered with ClinicalTrials.gov, number NCT02729571. Findings Between Sept 29, 2015, and Nov 16, 2015, 62 adults were screened and 18 were enrolled and randomly assigned, nine each to the BCG and MTBVAC groups. Between Feb 12, 2016, and Sept 21, 2016, 36 infants were randomly assigned—eight to the BCG group, nine to the 2·5 × 103 CFU MTBVAC group, nine to the 2·5 × 104 CFU group, and ten to the 2·5 × 105 CFU group. Mild injection-site reactions occurred only in infants in the BCG and the 2·5 × 105 CFU MTBVAC group, with no evidence of local or regional injection-site complications. Systemic adverse events were evenly distributed across BCG and MTBVAC dose groups, and were mostly mild in severity. Eight serious adverse events were reported in seven vaccine recipients (one adult MTBVAC recipient, one infant BCG recipient, one infant in the 2·5 × 103 CFU MTBVAC group, two in the 2·5 × 104 CFU MTBVAC group, and two in the 2·5 × 105 CFU MTBVAC group), including one infant in the 2·5 × 103 CFU MTBVAC group treated for unconfirmed tuberculosis and one in the 2·5 × 105 CFU MTBVAC group treated for unlikely tuberculosis. One infant died as a result of possible viral pneumonia. Vaccination with all MTBVAC doses induced durable antigen-specific T-helper-1 cytokine-expressing CD4 cell responses in infants that peaked 70 days after vaccination and were detectable 360 days after vaccination. For the highest MTBVAC dose (ie, 2·5 × 105 CFU), these responses exceeded responses induced by an equivalent dose of the BCG vaccine up to 360 days after vaccination. Dose-related IGRA conversion was noted in three (38%) of eight infants in the 2·5 × 103 CFU MTBVAC group, six (75%) of eight in the 2·5 × 104 CFU MTBVAC group, and seven (78%) of nine in the 2·5 × 105 CFU MTBVAC group at day 180, compared with none of seven infants in the BCG group. By day 360, IGRA reversion had occurred in all three infants (100%) in the 2·5 × 103 CFU MTBVAC group, four (67%) of the six in the 2·5 × 104 CFU MTBVAC group, and three (43%) of the seven in the 2·5 × 105 CFU MTBVAC group. Interpretation MTBVAC had acceptable reactogenicity, and induced a durable CD4 cell response in infants. The evidence of immunogenicity supports progression of MTBVAC into larger safety and efficacy trials, but also confounds interpretation of tests for M tuberculosis infection, highlighting the need for stringent endpoint definition. Funding Norwegian Agency for Development Cooperation, TuBerculosis Vaccine Initiative, UK Department for International Development, and Biofabri.

One third of the global population is estimated to be latently infected with Mycobacterium tuberculosis. We performed a phase I randomized controlled trial of isoniazid preventive therapy (IPT) before revaccination with bacillus Calmette–Guérin (BCG) in healthy, tuberculin skin test–positive (≥15-mm induration), HIV-negative South African adults. We hypothesized that preclearance of latent bacilli with IPT modulates BCG immunogenicity following revaccination. Frequencies and coexpression of IFN-γ, TNF-α, IL-2, IL-17, and/or IL-22 in CD4 T cells and IFN-γ–expressing CD8 T, γδ T, CD3+CD56+ NKT-like, and NK cells in response to BCG were measured using whole blood intracellular cytokine staining and flow cytometry. We analyzed 72 participants who were revaccinated with BCG after IPT (n = 33) or without prior IPT (n = 39). IPT had little effect on frequencies or cytokine coexpression patterns of M. tuberculosis– or BCG-specific responses. Revaccination transiently boosted BCG-specific Th1 cytokine-expressing CD4, CD8, and γδ T cells. Despite high frequencies of IFN-γ–expressing BCG-reactive CD3+CD56+ NKT-like cells and CD3−CD56dim and CD3−CD56hi NK cells at baseline, BCG revaccination boosted these responses, which remained elevated up to 1 y after revaccination. Such BCG-reactive memory NK cells were induced by BCG vaccination in infants, whereas in vitro IFN-γ expression by NK cells upon BCG stimulation was dependent on IL-12 and IL-18. Our data suggest that isoniazid preclearance of M. tuberculosis bacilli has little effect on the magnitude, persistence, or functional attributes of lymphocyte responses boosted by BCG revaccination. Our study highlights the surprising durability of BCG-boosted memory NKT-like and NK cells expressing antimycobacterial effector molecules, which may be novel targets for tuberculosis vaccines.

Summary The 4th Global Forum on TB Vaccines, convened in Shanghai, China, from 21 – 24 April 2015, brought together a wide and diverse community involved in tuberculosis vaccine research and development to discuss the current status of, and future directions for this critical effort. This paper summarizes the sessions on Developing TB Vaccines for Prevention of Disease, Prevention of Infection, and Immunotherapy Indications; Concepts and Approaches in Clinical Research & Development; and Epidemiological Research. Summaries of all sessions from the 4th Global Forum are compiled in a special supplement of Tuberculosis .

Healthcare workers (HCWs) are at high risk of Mycobacterium tuberculosis (Mtb) infection and tuberculosis disease, but also play a crucial role in implementing healthcare. Preexposure tuberculosis vaccination, including revaccination with BCG, might benefit Mtb-uninfected HCWs, but most HCWs in tuberculosis-endemic countries are already sensitized to mycobacteria. A new postexposure tuberculosis vaccine offers greatest potential for protection, in the setting of repeated occupational Mtb exposure. Novel strategies for induction of mycobacteria-specific resident memory T cells in the lung by aerosol administration, or induction of T cells with inherent propensity for residing in mucosal sites, such as CD1-restricted T cells and mucosa-associated innate T cells, should be explored. The need for improved protection of HCWs against tuberculosis disease is clear. However, health systems in tuberculosis-endemic countries would need significantly improved occupational health structures to implement a screening and vaccination strategy for HCWs.

Background Control of the tuberculosis epidemic requires a novel vaccine that is effective in preventing tuberculosis in adolescents, a key target population for vaccination against TB. Methods Healthy adolescents, stratified by M. tuberculosis -infection status, were enrolled into this observer-blinded phase II clinical trial of the protein-subunit vaccine candidate, H1:IC31, comprising a fusion protein (H1) of Ag85B and ESAT-6, formulated with the IC31 adjuvant. Local and systemic adverse events and induced T cell responses were measured after one or two administrations of either 15 μg or 50 μg of the H1 protein. Results Two hundred and forty participants were recruited and followed up for 224 days. No notable safety events were observed regardless of H1 dose or vaccination schedule. H1:IC31 vaccination induced antigen-specific CD4 T cells, co-expressing IFN-γ, TNF-α and/or IL-2. H1:IC31 vaccination of M.tb -uninfected individuals preferentially drove the emergence of Ag85B and ESAT-6 specific TNF-α + IL-2 + CD4 T cells, while H1:IC31 vaccination of M.tb -infected individuals resulted in the expansion of Ag85B-specific but not ESAT-6–specific TNF-α + IL-2 + CD4 T cells. Conclusions H1:IC31 was safe and immunogenic in uninfected and M.tb -infected adolescents. Two administrations of the 15 μg H1:IC31 dose induced the greatest magnitude immune response, and was considered optimal (South African National Clinical Trials Register, DoH-27-0612-3947 ; Pan African Clinical Trial Registry, PACTR201403000464306 ).

IntroductionHost blood transcriptomic biomarkers have potential as rapid point-of-care triage, diagnostic, and predictive tests for Tuberculosis disease. We aimed to summarise the performance of host blood transcriptomic signatures for diagnosis of and prediction of progression to Tuberculosis disease; and compare their performance to the recommended World Health Organisation target product profile.MethodsA systematic review and meta-analysis of the performance of host blood mRNA signatures for diagnosing and predicting progression to Tuberculosis disease in HIV-negative adults and adolescents, in studies with an independent validation cohort. Medline, Scopus, Web of Science, and EBSCO libraries were searched for articles published between January 2005 and May 2019, complemented by a search of bibliographies. Study selection, data extraction and quality assessment were done independently by two reviewers. Meta-analysis was performed for signatures that were validated in ≥3 comparable cohorts, using a bivariate random effects model.ResultsTwenty studies evaluating 25 signatures for diagnosis of or prediction of progression to TB disease in a total of 68 cohorts were included. Eighteen studies evaluated 24 signatures for TB diagnosis and 17 signatures met at least one TPP minimum performance criterion. Three diagnostic signatures were validated in clinically relevant cohorts to differentiate TB from other diseases, with pooled sensitivity 84%, 87% and 90% and pooled specificity 79%, 88% and 74%, respectively. Four studies evaluated signatures for progression to TB disease and performance of one signature, assessed within six months of TB diagnosis, met the minimal TPP for a predictive test for progression to TB disease.ConclusionHost blood mRNA signatures hold promise as triage tests for TB. Further optimisation is needed if mRNA signatures are to be used as standalone diagnostic or predictive tests for therapeutic decision-making.

Tuberculosis claims more human lives than any other infectious disease. This alarming epidemic has fuelled the development of novel antimicrobials and diagnostics. However, public health interventions that interrupt transmission have been slow to emerge, particularly in HIV-endemic settings. Transmission of tuberculosis is complex, involving various environmental, bacteriological, and host factors, among which concomitant HIV infection is important. Preventing person-to-person spread is central to halting the epidemic and, consequently, tuberculosis transmission is now being studied with renewed interest. In this Series paper, we review recent advances in the understanding of tuberculosis transmission, from the view of source-case infectiousness, inherent susceptibility of exposed individuals, appending tools for predicting risk of disease progression, the biophysical nature of the contagion, and the environments in which transmission occurs and is sustained in populations. We focus specifically on how HIV infection affects these features with a view to describing novel transmission blocking strategies in HIV-endemic settings.

Tuberculosis is a major cause of death and disability among children globally, yet children have been neglected in global tuberculosis control efforts. Historically, tuberculosis in children has been thought of as a family disease, and because of this, household contact tracing of children after identification of an adult tuberculosis case has been emphasised as the principal public health intervention. However, the population-level effect of household contact tracing is predicated on the assumption that most paediatric tuberculosis infections are acquired within the household. In this Personal View, we focus on accumulating scientific evidence indicating that the majority of Mycobacterium tuberculosis transmission to children in high-burden settings occurs in the community, outside of households in which a person has tuberculosis. We estimate the population-attributable fraction of M tuberculosis transmission to children due to household exposures to be between 10% and 30%. M tuberculosis transmission from the household was low (

Eradication of tuberculosis (TB), the world's leading cause of death due to infectious disease, requires a highly efficacious TB vaccine. Many TB vaccine candidates are in pre-clinical and clinical development but only a few can be advanced to large-scale efficacy trials due to limited global resources. We aimed to perform a statistically rigorous comparison of the antigen-specific T cell responses induced by six novel TB vaccine candidates and the only licensed TB vaccine, Bacillus Calmette-Guérin (BCG). We propose that the antigen-specific immune response induced by such vaccines provides an objective, data-driven basis for prioritisation of vaccine candidates for efficacy testing. We analyzed frequencies of antigen-specific CD4 and CD8 T cells expressing IFNγ, IL-2, TNF and/or IL-17 from adolescents or adults, with or without Mycobacterium tuberculosis (M.tb) infection, who received MVA85A, AERAS-402, H1:IC31, H56:IC31, M72/AS01E, ID93+GLA-SE or BCG. Two key response characteristics were analyzed, namely response magnitude and cytokine co-expression profile of the memory T cell response that persisted above the pre-vaccination response to the final study visit in each trial. All vaccines preferentially induced antigen-specific CD4 T cell responses expressing Th1 cytokines; levels of IL-17-expressing cells were low or not detected. In M.tb-uninfected and -infected individuals, M72/AS01E induced higher memory Th1 cytokine-expressing CD4 T cell responses than other novel vaccine candidates. Cytokine co-expression profiles of memory CD4 T cells induced by different novel vaccine candidates were alike. Our study suggests that the T cell response feature which most differentiated between the TB vaccine candidates was response magnitude, whilst functional profiles suggested a lack of response diversity. Since M72/AS01E induced the highest memory CD4 T cell response it demonstrated the best vaccine take. In the absence of immunological correlates of protection, the likelihood of finding a protective vaccine by empirical testing of candidates may be increased by the addition of candidates that induce distinct immune characteristics., Author summary Tuberculosis (TB) causes more deaths than any other single infectious disease, and a new, improved vaccine is needed to control the epidemic. Many new TB vaccine candidates are in clinical development, but only one or two can be advanced to expensive efficacy trials. In this study, we compared magnitude and functional attributes of memory T cell responses induced in recently conducted clinical trials by six TB vaccine candidates, as well as BCG. The results suggest that these vaccines induced CD4 and CD8 T cell responses with similar functional attributes, but that one vaccine, M72/AS01E, induced the largest responses. This finding may indicate a lack of diversity in T cell responses induced by different TB vaccine candidates. A repertoire of vaccine candidates that induces more diverse immune response characteristics may increase the chances of finding a protective vaccine against TB.

BACKGROUND: A vaccine to interrupt the transmission of tuberculosis is needed. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 2b trial of the M72/AS01E tuberculosis vaccine in Kenya, South Africa, and Zambia. Human immunodeficiency virus (HIV)-negative adults 18 to 50 years of age with latent M. tuberculosis infection (by interferon-γ release assay) were randomly assigned (in a 1:1 ratio) to receive two doses of either M72/AS01E or placebo intramuscularly 1 month apart. Most participants had previously received the bacille Calmette-Guérin vaccine. We assessed the safety of M72/AS01E and its efficacy against progression to bacteriologically confirmed active pulmonary tuberculosis disease. Clinical suspicion of tuberculosis was confirmed with sputum by means of a polymerase-chain-reaction test, mycobacterial culture, or both. RESULTS: We report the primary analysis (conducted after a mean of 2.3 years of follow-up) of the ongoing trial. A total of 1786 participants received M72/AS01E and 1787 received placebo, and 1623 and 1660 participants in the respective groups were included in the according-to-protocol efficacy cohort. A total of 10 participants in the M72/AS01E group met the primary case definition (bacteriologically confirmed active pulmonary tuberculosis, with confirmation before treatment), as compared with 22 participants in the placebo group (incidence, 0.3 cases vs. 0.6 cases per 100 person-years). The vaccine efficacy was 54.0% (90% confidence interval [CI], 13.9 to 75.4; 95% CI, 2.9 to 78.2; P=0.04). Results for the total vaccinated efficacy cohort were similar (vaccine efficacy, 57.0%; 90% CI, 19.9 to 76.9; 95% CI, 9.7 to 79.5; P=0.03). There were more unsolicited reports of adverse events in the M72/AS01E group (67.4%) than in the placebo group (45.4%) within 30 days after injection, with the difference attributed mainly to injection-site reactions and influenza-like symptoms. Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two groups. CONCLUSIONS: M72/AS01E provided 54.0% protection for M. tuberculosis-infected adults against active pulmonary tuberculosis disease, without evident safety concerns. (Funded by GlaxoSmithKline Biologicals and Aeras; ClinicalTrials.gov number, NCT01755598 .).

Purpose of review To outline the need for a new tuberculosis (TB) vaccine; challenges for induction of vaccine-mediated protection in HIV-infected persons; and recent advances in clinical development. Recent findings HIV has a detrimental effect on T-cell function, polarization and differentiation of Mycobacterium tuberculosis (Mtb)-specific T cells, Mtb antigen presentation by dendritic cells, and leads to B-cell and antibody-response deficiencies. Previous observations of protection against TB disease in HIV-infected persons by Mycobacterium obuense suggest that an effective vaccine against HIV-related TB is feasible. Studies of inactivated mycobacterial, viral-vectored and protein subunit vaccines reported lower immune responses in HIV-infected relative to HIV-uninfected individuals, which were only partially restored with antiretroviral therapy. Bacille Calmette Guerin (BCG) revaccination of HIV-uninfected adolescents recently showed moderate efficacy against sustained Mtb infection, but live mycobacterial vaccines have an unfavorable risk profile for HIV-infected persons. Ongoing trials of inactivated mycobacterial and protein-subunit vaccines in HIV-uninfected, Mtb-infected adults may be more relevant for protection of HIV-infected populations in TB endemic countries. Summary New TB vaccine candidates have potential to protect against HIV-related TB, through vaccination prior to or after HIV acquisition, but this potential may only be realized after efficacy is demonstrated in HIV-uninfected populations, with or without Mtb infection.

Recent Mycobacterium tuberculosis infection confers a predisposition to the development of tuberculosis disease, the leading killer among global infectious diseases. H4:IC31, a candidate subunit vaccine, has shown protection against tuberculosis disease in preclinical models, and observational studies have indicated that primary bacille Calmette-Guérin (BCG) vaccination may offer partial protection against infection.In this phase 2 trial, we randomly assigned 990 adolescents in a high-risk setting who had undergone neonatal BCG vaccination to receive the H4:IC31 vaccine, BCG revaccination, or placebo. All the participants had negative results on testing for M. tuberculosis infection on the QuantiFERON-TB Gold In-tube assay (QFT) and for the human immunodeficiency virus. The primary outcomes were safety and acquisition of M. tuberculosis infection, as defined by initial conversion on QFT that was performed every 6 months during a 2-year period. Secondary outcomes were immunogenicity and sustained QFT conversion to a positive test without reversion to negative status at 3 months and 6 months after conversion. Estimates of vaccine efficacy are based on hazard ratios from Cox regression models and compare each vaccine with placebo.Both the BCG and H4:IC31 vaccines were immunogenic. QFT conversion occurred in 44 of 308 participants (14.3%) in the H4:IC31 group and in 41 of 312 participants (13.1%) in the BCG group, as compared with 49 of 310 participants (15.8%) in the placebo group; the rate of sustained conversion was 8.1% in the H4:IC31 group and 6.7% in the BCG group, as compared with 11.6% in the placebo group. Neither the H4:IC31 vaccine nor the BCG vaccine prevented initial QFT conversion, with efficacy point estimates of 9.4% (P=0.63) and 20.1% (P=0.29), respectively. However, the BCG vaccine reduced the rate of sustained QFT conversion, with an efficacy of 45.4% (P=0.03); the efficacy of the H4:IC31 vaccine was 30.5% (P=0.16). There were no clinically significant between-group differences in the rates of serious adverse events, although mild-to-moderate injection-site reactions were more common with BCG revaccination.In this trial, the rate of sustained QFT conversion, which may reflect sustained M. tuberculosis infection, was reduced by vaccination in a high-transmission setting. This finding may inform clinical development of new vaccine candidates. (Funded by Aeras and others; C-040-404 ClinicalTrials.gov number, NCT02075203 .).