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To determine the levels and patterns of resistance to first- and second-line anti-tuberculosis (TB) drugs among new and previously treated sputum smear positive pulmonary TB (PTB) patients.We conducted a nationally representative cross-sectional facility-based survey in June 2017-July 2018 involving 45 clusters selected based on probability proportional to size. The survey aimed to determine the prevalence of anti-TB drug resistance and associated risk factors among smear positive PTB patients in Tanzania. Sputum samples were examined using smear microscopy, Xpert MTB/RIF, culture and drug susceptibility testing (DST). Logistic regression was used to account for missing data and sampling design effects on the estimates and their standard errors.We enrolled 1557 TB patients, including 1408 (90.4%) newly diagnosed and 149 (9.6%) previously treated patients. The prevalence of multidrug-resistant TB (MDR-TB) was 0.85% [95% confidence interval (CI): 0.4-1.3] among new cases and 4.6% (95% CI: 1.1-8.2) among previously treated cases. The prevalence of Mycobacterium tuberculosis strains resistant to any of the four first-line anti-TB drugs (isoniazid, rifampicin, streptomycin and ethambutol) was 1.7% among new TB patients and 6.5% among those previously treated. Drug resistance to all first-line drugs was similar (0.1%) in new and previously treated patients. None of the isolates displayed poly-resistance or extensively drug-resistant TB (XDR-TB). The only risk factor for MDR-TB was history of previous TB treatment (odds ratio = 5.7, 95% CI: 1.9-17.2).The burden of MDR-TB in the country was relatively low with no evidence of XDR-TB. Given the overall small number of MDR-TB cases in this survey, it will be beneficial focusing efforts on intensified case detection including universal DST.

Centrally necrotizing granulomas that harbor Mycobacterium tuberculosis (Mtb) are the hallmark of human tuberculosis (TB). New anti-TB therapies will need to effectively penetrate the cellular and necrotic, non-vascularized compartments of these lesions and reach sufficient concentrations to eliminate Mtb. BTZ‑043 is a novel antibiotic showing good bactericidal activity in humans in a phase IIa trial. Here, we report on the substantial efficacy of BTZ‑043 in the advanced pre-clinical model of interleukin-13-overexpressing mice, which mimic human TB pathology of pulmonary central granuloma necrosis. Accordingly, pulmonary BTZ‑043 concentrations were severalfold above the minimal inhibitory concentration in these mice. The detailed histological characterization of lung granulomas in combination with high resolution MALDI imaging revealed that BTZ‑043 diffuses and accumulates in the cellular compartment, and fully penetrates the necrotic center. In summary, this study is the first visualizing an efficient penetration, accumulation, and retention of a clinical-stage TB drug in human-like centrally necrotizing granulomas.

IntroductionArboviruses and malaria are both mosquito-borne diseases, with overlapping symptoms and geographic distribution in tropical settings. However, little information is available on the co-occurrence of arboviruses and malaria in areas highly endemic for malaria in Africa. This study was conducted with the aim to determine the frequency of recent Dengue (DENV), Chikungunya (CHIKV) and Zika (ZIKV) infections and their co-occurrence with malaria in six highly endemic districts for malaria in Mozambique.MethodsBlood samples were collected from febrile outpatients between January 2017 and December 2018 and were then tested for Malaria using RDT. Serum samples from these patients were also tested using commercially available ELISA for the presence of IgM antibodies against CHIKV, ZIKV and DENV, as well as NS1 antigen for DENV. Concurrently, a questionnaire was administered to collect socio-demographic characteristics of patients.ResultsOf the 906 participants enrolled, IgM antibodies against CHIKV, DENV and ZIKV were identified in 134 (14.8%), 64 (7.4%) and 83 (9.2%) individuals, respectively. Malaria was diagnosed in 56 (6.2%) participants, of which 16 (28.6%) were also positive for IgM anti CHIKV, 1 (1.8%) for DENV-NS1, 3 (5.4%) for IgM anti-DENV and 10 (17.8%) for IgM anti-ZIKV. There was a trend towards an increase in the frequency of IgM anti CHIKV positive samples, from 7.0% in 2014 to 14.8% in 2018 and IgM anti-ZIKV positive samples increased from 4.9% in 2015 to 9.2% in 2018.ConclusionThis study showed an increased frequency of arbovirus in Mozambique thus far, as well as a frequent occurrence of arbovirus among malaria positive patients. This highlighted the urgency for the establishment of sentinel surveillance sites for arboviruses and the need for an integrated management of febrile illnesses in places where arboviruses and malaria are both prevalent.AUTHOR SUMMARYArbovirus and malaria share clinical features, which might make the differential diagnosis of acute febrile illnesses significantly difficult, leading to frequent over diagnosis of malaria and under diagnosis of arbovirus in places where both co-occur. In Mozambique and other sub-Saharan countries, epidemiological data on the burden and temporal trend of arbovirus, as well as on co-occurrence with malaria are Chikungunya virus (CHIKV) and Dengue virus (DENV) and its co-occurrence with malaria among 609 febrile patients in six health centres located in five provinces in Mozambique. Recent CHIKV, DENV and ZIKV infection, as measured by presence of IgM antibodies, were found in 14.8%, 7.4% and 9.2% of participants and among 28.6%, 5.4% and 17.8%, of malaria positive patients. These findings suggest that arboviruses are frequent among malaria and non-malaria febrile patients, reinforcing the need for increased awareness of arbovirus in the management of acute febrile illness.

This study set out to determine the occurrence of phylogenetic lineages of M.tb complex and to examine their relationship with patient demographic characteristics and multidrug-resistant TB (MDR-TB) among pulmonary TB patients enrolled during the second national anti-TB drug resistance survey in Tanzania. A cross-sectional survey was conducted involving a sample of new smear-positive pulmonary TB and previously treated individuals. Sputum samples were collected and transported to the Central TB Reference Laboratory (CTRL) in Dar es Salaam, Tanzania for smear microscopy, culture, strain identification and susceptibility testing following standard National TB and Leprosy Programme (NTLP) guidelines. For WGS, all culture positive isolates were shipped to the National TB Reference Laboratory/Supranational Tuberculosis Reference Laboratory in Uganda. The isolates were sub-cultured on selective Middlebrook 7H11 agar. High quality genomic DNA was extracted using an in-house cetyl trimethylammonium bromide (CTAB) method. Genomic libraries were sequenced using the Illumina MiSeq V3 cartridge. Tools for resistance profiling and lineage inference (Kvarq v0.12.2, Mykrobe v0.8.1 and TBprofiler v3.0.5) were ran. De novo genome assembly of all samples was done using Unicycler v0.4.8. The resulting trees were plotted, annotated and visualized using ggtree v2.0.4. &nbsp

Bacterial killing in TB-patients with relapse was compared to patients achieving cure, measured by TB-molecular bacterial load assay(TB-MBLA) or MGIT time to positivity(TTP). TB-MBLA in 4 relapsed patients was significantly different compared to 132 cured patients after 2 weeks of treatment; MGIT TTP showed a significant difference from week 8.

Objectives: The aim of this study was to detect the seroprevalence of Crimean–Congo haemorrhagic fever virus (CCHFV) in patients with fever of unknown origin (FUO) in endemic (Kyzylorda) and non-endemic (Almaty) oblasts of Kazakhstan. Methods: Paired serum samples from 802 patients with FUO were collected. Serum samples were investigated by ELISA to detect IgG and IgM antibodies against CCHFV. Sera with suspected acute infection were further investigated by RT-PCR to detect the viral RNA. Results: IgG antibodies were detected in 12.7% of the sera from both oblasts. Acute infection was shown by IgM ELISA in four patients from Kyzylorda, with only one developing severe CCHF. Viral RNA was found by RT-PCR in the other three patients’ sera. Phylogenetic analysis of partial L and S segments revealed CCHFV genotype Asia 2 and a possible reassortment between the genotypes Asia 1/Asia 2. Animal husbandry, such as working with cattle and horses, was significantly associated with CCHFV seropositivity. Conclusions: The antibodies and viral RNA detected in sera indicate that mild or even asymptomatic CCHFV infections are presented in Kazakhstan. This study describes the circulation of CCHFV in the so far non-endemic Almaty oblast for the first time. In conclusion, physicians treating patients with FUO in Kazakhstan should be aware of mild CCHF. Keywords: Crimean–Congo haemorrhagic fever virus, Fever of unknown origin, Reassortment, Kazakhstan

IntroductionThe WHO End-TB Strategy calls for the development of novel diagnostics to detect tuberculosis (TB) earlier and more accurately. Better diagnostics, together with tools to predict disease progression, are critical for achieving WHO End-TB targets. The Early Risk Assessment in TB Contacts by new diagnoStic tEsts (ERASE-TB) study aims to evaluate novel diagnostics and testing algorithms for early TB diagnosis and accurate prediction of disease progression among household contacts (HHCs) exposed to confirmed index cases in Mozambique, Tanzania and Zimbabwe.Methods and analysisA total of 2100 HHCs (aged ≥10 years) of adults with microbiologically-confirmed pulmonary TB will be recruited and followed up at 6-month intervals for 18–24 months. At each time point, a WHO symptom screen and digital chest radiograph (dCXR) will be performed, and blood and urine samples will be collected. Individuals screening positive (WHO symptom screen or dCXR) will be requested to provide sputum for Xpert MTB/Rif Ultra. At baseline, HHCs will also be screened for HIV, diabetes (HbA1c), chronic lung disease (spirometry), hypertension and anaemia. Study outcomes will be coprevalent TB (diagnosed at enrolment), incident TB (diagnosed during follow-up) or no TB at completion of follow-up. Novel diagnostics will be validated using fresh and biobanked samples with a nested case–control design. Cases are defined as HHCs diagnosed with TB (for early diagnosis) or with incident TB (for prediction of progression) and will be matched by age, sex and country to HHCs who remain healthy (controls). Statistical analyses will include assessment of diagnostic accuracy by constructing receiver operating curves and calculation of sensitivity and specificity.Ethics and disseminationERASE-TB has been approved by regulatory and ethical committees in each African country and by each partner organisation. Consent, with additional assent for participants Trial registration numberNCT04781257.Cite Now

Pyrazinamide is a potent sterilising agent that shortens the treatment duration needed to cure tuberculosis. It is synergistic with novel and existing drugs for tuberculosis. The dose of pyrazinamide that optimises efficacy while remaining safe is uncertain, as is its potential role in shortening treatment duration further.Pharmacokinetic data, sputum culture, and safety laboratory results were compiled from Tuberculosis Trials Consortium (TBTC) studies 27 and 28 and Pan-African Consortium for the Evaluation of Antituberculosis Antibiotics (PanACEA) multi-arm multi-stage tuberculosis (MAMS-TB), multi-centre phase 2 trials in which participants received rifampicin (range 10–35 mg·kg−1), pyrazinamide (range 20–30 mg·kg−1), plus two companion drugs. Pyrazinamide pharmacokinetic–pharmacodynamic (PK–PD) and pharmacokinetic-toxicity analyses were performed.In TBTC studies (n=77), higher pyrazinamide maximum concentration (Cmax) was associated with shorter time to culture conversion (TTCC) and higher probability of 2-month culture conversion (p-valuemax increased and varied by rifampicin area under the curve (p-value4500 mg) or increasing both pyrazinamide and rifampicin would be required to reach targets associated with treatment shortening. Combining all trials, liver toxicity was rare (3.9% with grade 3 or higher liver function tests (LFT)), and no relationship was seen between pyrazinamide Cmax and LFT levels.Pyrazinamide's microbiological efficacy increases with increasing drug concentrations. Optimising pyrazinamide alone, though, is unlikely to be sufficient to allow tuberculosis treatment shortening; rather, rifampicin dose would need to be increased in parallel.

Objectives This study investigated the molecular epidemiology of respiratory syncytial virus (RSV) among febrile children with acute respiratory tract infection in Ghana, Gabon, Tanzania and Burkina Faso between 2014 and 2017 as well as the evolution and diversification of RSV strains from other sub-Saharan countries. Methods Pharyngeal swabs were collected at four study sites (Agogo, Ghana: n = 490; Lambarene, Gabon: n = 182; Mbeya, Tanzania: n = 293; Nouna, Burkina Faso: n = 115) and analysed for RSV and other respiratory viruses using rtPCR. For RSV-positive samples, sequence analysis of the second hypervariable region of the G gene was performed. A dataset of RSV strains from sub-Saharan Africa (2011-2017) currently available in GenBank was compiled. Phylogenetic analysis was conducted to identify the diversity of circulating RSV genotypes. Results In total, 46 samples were tested RSV positive (Ghana n = 31 (6.3%), Gabon n = 4 (2.2%), Tanzania n = 9 (3.1%) and Burkina Faso n = 2 (1.7%)). The most common RSV co-infection was with rhinovirus. All RSV A strains clustered with genotype ON1 strains with a 72-nucleotide duplication and all RSV B strains belonged to genotype BAIX. Phylogenetic analysis of amino acid sequences from sub-Saharan Africa revealed the diversification into 11 different ON1 and 22 different BAIX lineages and differentiation of ON1 and BAIX strains into potential new sub-genotypes, provisionally named ON1-NGR, BAIX-KEN1, BAIX-KEN2 and BAIX-KEN3. Conclusion The study contributes to an improved understanding of the molecular epidemiology of RSV infection in sub-Saharan Africa. It provides the first phylogenetic data for RSV from Tanzania, Gabon and Burkina Faso and combines it with RSV strains from all other sub-Saharan countries currently available in GenBank.

Background Accumulating data indicate that higher rifampicin doses are more effective and shorten tuberculosis (TB) treatment duration. This study evaluated the safety, tolerability, pharmacokinetics, and 7- and 14-day early bactericidal activity (EBA) of increasing doses of rifampicin. Here we report the results of the final cohorts of PanACEA HIGHRIF1, a dose escalation study in treatment-naive adult smear-positive patients with TB. Methods Patients received, in consecutive cohorts, 40 or 50 mg·kg−1 rifampicin once daily in monotherapy (day 1–7), supplemented with standard dose isoniazid, pyrazinamide and ethambutol between days 8 and 14. Results In the 40 mg·kg−1 cohort (n=15), 13 patients experienced a total of 36 adverse events during monotherapy, resulting in one treatment discontinuation. In the 50 mg·kg−1 cohort (n=17), all patients experienced adverse events during monotherapy, 93 in total; 11 patients withdrew or stopped study medication. Adverse events were mostly mild/moderate and tolerability rather than safety related, i.e. gastrointestinal disorders, pruritis, hyperbilirubinaemia and jaundice. There was a more than proportional increase in the rifampicin geometric mean area under the plasma concentration–time curve from time 0 to 12 h (AUC0–24 h) for 50 mg·kg−1 compared with 40 mg·kg−1; 571 (range 320–995) versus 387 (range 201–847) mg·L−1·h, while peak exposures saw proportional increases. Protein-unbound exposure after 50 mg·kg−1 (11% (range 8–17%)) was comparable with lower rifampicin doses. Rifampicin exposures and bilirubin concentrations were correlated (Spearman's ρ=0.670 on day 3, p, While bactericidal activity continues to increase with dose, for the first time we identified dose-limiting intolerability for rifampicin dosed at 50 mg·kg−1; 40 mg·kg−1 seems the optimal tolerable dose for evaluation in TB treatment-shortening trials https://bit.ly/37dUIuB

Contains fulltext : 220733.pdf (Publisher’s version ) (Open Access) In this comparative biomarker study, we analysed 1768 serial sputum samples from 178 patients at 4 sites in Southeast Africa. We show that tuberculosis Molecular Bacterial Load Assay (TB-MBLA) reduces time-to-TB-bacillary-load-result from days/weeks by culture to hours and detects early patient treatment response. By day 14 of treatment, 5% of patients had cleared bacillary load to zero, rising to 58% by 12th week of treatment. Fall in bacillary load correlated with mycobacterial growth indicator tube culture time-to-positivity (Spearmans r=-0.51, 95% CI (-0.56 to -0.46), p

Background: Accumulating data indicate that higher rifampicin doses may be more effective and shorten tuberculosis treatment duration. This study evaluated the safety, tolerability, pharmacokinetics, and 14-day early bactericidal activity (EBA) of increasing doses of rifampicin. Methods: We performed a dose-escalation study in treatment-naive adult smear-positive tuberculosis patients. Patients received, in consecutive cohorts, 40 or 50mg/kg rifampicin once daily in monotherapy (day 1-7), supplemented with standard doses of isoniazid, pyrazinamide and ethambutol between day 8-14. Safety, tolerability, pharmacokinetics, and EBA were assessed. Findings: In the 40mg/kg cohort (n=15), 13 patients experienced adverse events (AEs) during monotherapy (n=36), resulting in one treatment discontinuation in the combination phase. In the 50mg/kg group (n=17), all patients experienced AEs during monotherapy. There were more AEs in total (n=93) compared to 40mg/kg, and eleven patients withdrew or stopped study medication. AEs were mostly mild or moderate (≤grade 3) and tolerability related, i.e. gastrointestinal disorders, pruritis, hyperbilirubinemia and jaundice. A more than proportional increase in rifampicin exposure with dose was observed, in line with previous cohorts. EBA increased considerably with dose; with the highest seen in the 50mg/kg cohort. Interpretation: Our research concludes a journey that started in the 1960s. Rifampicin up to 40mg/kg was well tolerated. Although associated with an increased bactericidal effect, the tolerability of a 50mg/kg dose was poor. Rifampicin at 40mg/kg appears to be the optimal dose for evaluation in a phase IIB/C treatment shortening trial. Trial Registration: Here we report the results of the final cohorts of the PanACEA HIGHRIF1 trial (clinicaltrials.gov NCT01392911). Funding Statement: This publication was produced by PanACEA, which is part of the European and Developing Countries Clinical Trials Partnership (EDCTP) 1 programme [project code IP.2007.32011.012 (HIGHRIF)] and the EDCTP2 programme supported by the European Union (grant number TRIA2015-1102-PanACEA). Declaration of Interests: We declare no competing interests. Ethics Approval Statement: The study protocol was approved by the applicable ethical review boards and by the South African Health Products Regulatory Authority and was conducted according to international and South African Good Clinical Practice guidelines.

The 5th CIHLMU Infectious Disease Symposium, Munich, Germany, March 12, 2016 brought together Tuberculosis Experts from developed and low middle-income countries to discuss the control of drug resistance Tuberculosis. The meeting featured 9 presentations: Tuberculosis history and current scenario, Tuberculosis and migration - current scenario in Germany, Mechanism of Tuberculosis resistance development, Epidemiology of resistance – transmission vs. new generation of resistance, The impact of diagnostic in patients beyond – sensitivity and specificity, The Bangladesh regimen – new hope trough old drugs, New drugs and regimens – an overview on studies and Multi and Extensively Drug Resistant Tuberculosis from Europe. The presentations were followed by a panel discussion. Serious Multidrug Resistance epidemic in some countries may jeopardize the progress in Tuberculosis control. In this meeting epidemiology, mechanism, immigration and screening, diagnosis, research and treatment of drug resistant tuberculosis were discussed.

Greater Banjul Area of the Gambia.To identify co-prevalent tuberculosis (TB) among child contacts of adults with smear-positive TB.Child contacts aged

The study was supported by the German Ministry of Education and Research (BMBF, Grant No. 01KA0901 ) and the European and Developing Countries Clinical Trials Partnership (EDCTP, Project-ID: IP.2007.32011.011 ). The Xpert MTB/RIF assay detects Mycobacterium tuberculosis in unprocessed or NALC/NaOH- decontaminated sputum. The effect of repeated NALC/NaOH-decontamination on several Xpert performance parameters was assessed in this study. A second NALC/NaOH-decontamination had no effect on the binary Xpert-outcome but increased the value for the quantitative readout (CTmin). Repeated decontamination was not associated with PCR-inhibition or invalid results. The CTmin of M.tb positive samples was higher in inhibited Xpert runs. Our data indicate that NALC/NaOH-decontamination has an effect on the performance of the Xpert assay, and that CTmin readouts of decontaminated sputum samples should be interpreted with caution. Postprint

ObjectivesBetter outcomes in tuberculosis require new diagnostic and treatment monitoring tools. In this paper we evaluated the utility of a marker ofM. tuberculosisviable count, the Molecular Bacterial Load assay (MBLA) for diagnosis and treatment monitoring of tuberculosis in a high burden setting.MethodsPatients with smear positive pulmonary tuberculosis from two sites in Tanzania and one each in Malawi and Mozambique. Sputum samples were taken weekly for the first 12 weeks of treatment and evaluated by MBLA and mycobacterial growth indicator tube method (MGIT).ResultsThe results of high and low positive control samples confirmed inter site reproducibility. Over the 12 weeks of treatment there was a steady decline in the viable bacterial load as measured by the MBLA that corresponds to rise in time to a positive result (TTP) in the Mycobacterial Growth Indicator Tube. Both MBLA and MGIT provided similar time to test negativity. Importantly, as treatment progressed samples in MGIT were increasingly likely to be contaminated, which compromised the acquisition of results but did not affect MBLA samples.ConclusionsMBLA produces a reproducible measure ofMtbviable count comparable to that of MGIT that is not compromised by contamination in a real-world setting. As a molecular test, the results can be available in as little as four hours and could allow health care professionals to identify rapidly patients who are failing therapy.

BackgroundAccumulating data indicate that higher rifampicin doses are more effective and shorten tuberculosis (TB) treatment duration. This study evaluated the safety, tolerability, pharmacokinetics, and 7- and 14-day early bactericidal activity (EBA) of increasing doses of rifampicin. Here we report the results of the final cohorts of PanACEA HIGHRIF1, a dose escalation study in treatment-naive adult smear-positive patients with TB.MethodsPatients received, in consecutive cohorts, 40 or 50 mg·kg−1 rifampicin once daily in monotherapy (day 1–7), supplemented with standard dose isoniazid, pyrazinamide and ethambutol between days 8 and 14.ResultsIn the 40 mg·kg−1 cohort (n=15), 13 patients experienced a total of 36 adverse events during monotherapy, resulting in one treatment discontinuation. In the 50 mg·kg−1 cohort (n=17), all patients experienced adverse events during monotherapy, 93 in total; 11 patients withdrew or stopped study medication. Adverse events were mostly mild/moderate and tolerability rather than safety related, i.e. gastrointestinal disorders, pruritis, hyperbilirubinaemia and jaundice. There was a more than proportional increase in the rifampicin geometric mean area under the plasma concentration–time curve from time 0 to 12 h (AUC0–24 h) for 50 mg·kg−1 compared with 40 mg·kg−1; 571 (range 320–995) versus 387 (range 201–847) mg·L−1·h, while peak exposures saw proportional increases. Protein-unbound exposure after 50 mg·kg−1 (11% (range 8–17%)) was comparable with lower rifampicin doses. Rifampicin exposures and bilirubin concentrations were correlated (Spearman's ρ=0.670 on day 3, p−1: 14-day EBA −0.427 (95% CI −0.500– −0.355) log10CFU·mL−1·day−1.ConclusionAlthough associated with an increased bactericidal effect, the 50 mg·kg−1 dose was not well tolerated. Rifampicin at 40 mg·kg−1 was well tolerated and therefore selected for evaluation in a phase IIc treatment-shortening trial.

Background The population structure and drug resistance pattern of Mycobacterium tuberculosis complex (MTBC) isolates in Ethiopian prisons and some communities is still unknown. Methods A comparative cross sectional study was conducted on 126 MTBC strains isolated from prisons and communities in southwestern, southern and eastern Ethiopia. Phenotypic drug susceptibility testing was performed with the MGIT960 system. Combined 24-loci Mycobacterium interspersed repetitive unit-variable number tandem repeat and spacer oligonucleotide typing methods were used to study the MTBC population structure. The obtained data from prisons and communities were compared using statistical tests and regression analysis. Results A diverse population structure with 11 different lineages and sub-lineages was identified. The predominant strains were the recently described Ethiopia_H37Rv like (27.52%) and Ethiopia_3 (16.51%) with equal lineage distribution between prisons and communities. 28.57% of prison strains and 31.82% of community strains shared the identical genotype with at least one other strain. The multidrug-resistance (MDR) prevalence of the community was 2.27% whereas that of prisons was 9.52%. The highest mono resistance was seen against streptomycin (15.89%). Conclusion Tuberculosis in communities and prisons is caused by a variety of MTBC lineages with predominance of local Ethiopian lineages. The increasing prevalence of MDR MTBC strains is alarming. These findings suggest the need for new approaches for control of MDR tuberculosis in Ethiopia. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-2041-x) contains supplementary material, which is available to authorized users.

A conference called "Outbreaks in Tanzania-Are We Prepared?" was held in Mbeya, Tanzania, on September 14 and 15, 2015, accompanied by a training workshop on infection prevention and control for local stakeholders from September 16 to 18, 2015. The objective of the conference was to revisit past disease epidemics and to reflect on the current status of surveillance and outbreak preparedness in Tanzania, including an overview of agents relevant to biosecurity. The conference brought together national authorities of Tanzania, regional public health representatives, people from research and academic institutions, and international stakeholders. Key findings of the event were: (1) although national frameworks for surveillance and preparedness exist, their implementation presents challenges, and local health structures need support in implementation; (2) the ability to identify and properly manage infectious diseases of public health concern is crucial in empowering the local health workforce to contribute to surveillance measures, which in turn allows for realistic risk assessments and management algorithms; and (3) in settings of limited resources, research activities acquire an additional responsibility toward national surveillance and capacity building and should be integrated into national epidemic preparedness plans. This event was the first of its kind in Tanzania, facilitating direct discussion among regional, zonal, national, and international stakeholders on surveillance and outbreak preparedness. The conference's conclusions are relevant to strengthening health systems in other low- and middle-income countries.

This work was supported by the European and Developing Countries Clinical Trials partnership (grants IP.2007.32011.011, IP.2007.32011.012, and IP.2007.32011.013) and the German Ministry for Education and Research (grant 01KA0901). The original study conducted within the PanACEA consortium. Background: Tuberculosis remains a huge public health problem and the prolonged treatment duration obstructs effective tuberculosis control. Higher rifampicin doses have been associated with better bactericidal activity, but optimal dosing is uncertain. This analysis aimed to characterize the relationship between rifampicin plasma exposure and treatment response over 6 months in a recent study investigating the potential for treatment shortening with high-dose rifampicin. Methods: Data were analyzed from 336 patients with pulmonary tuberculosis (97 with pharmacokinetic data) treated with rifampicin doses of 10, 20, or 35 mg/kg. The response measure was time to stable sputum culture conversion (TSCC). We derived individual exposure metrics with a previously developed population pharmacokinetic model of rifampicin. TSCC was modeled using a parametric time-to-event approach, and a sequential exposure-response analysis was performed. Results: Higher rifampicin exposures increased the probability of early culture conversion. No maximal limit of the effect was detected within the observed range. The expected proportion of patients with stable culture conversion on liquid medium at week 8 was predicted to increase from 39% (95% confidence interval, 37%-41%) to 55% (49%-61%), with the rifampicin area under the curve increasing from 20 to 175 mg/L·h (representative for 10 and 35 mg/kg, respectively). Other predictors of TSCC were baseline bacterial load, proportion of culture results unavailable, and substitution of ethambutol for either moxifloxacin or SQ109. Conclusions: Increasing rifampicin exposure shortened TSCC, and the effect did not plateau, indicating that doses >35 mg/kg could be yet more effective. Optimizing rifampicin dosage while preventing toxicity is a clinical priority. Publisher PDF

We evaluated the diagnostic performance of two tests based on the release of lipoarabinomannan (LAM) into the urine, the MTB-LAM-ELISA assay and the Determine TB-LAM-strip assay, in children with suspected tuberculosis (TB) in a high TB/HIV-prevalence setting.In a prospective study, 132 children with suspected active TB were assigned to diagnostic subgroups. Urine samples were subjected to testing by both assays to ascertain sensitivity and specificity. Host factors associated with positive LAM results were investigated and LAM excretion monitored after antituberculous treatment initiation.18 (13.6%) children had culture-confirmed pulmonary TB. The assays' sensitivity was higher in HIV-positiveversusHIV-negative children: 70% (95% confidence interval 35–93%)versus13% (0–53%) for MTB-LAM-ELISA and 50% (19–81%)versus0% (0–37%) for Determine TB-LAM. In 35 (27%) children with excluded active TB, both assays showed a specificity of 97.1% (85–100%). Proteinuria and low body mass index were independently associated with LAM positivity. In most patients, LAM excretion declined to zero during or at conclusion of antituberculous treatment.HIV/TB co-infected children might benefit from LAM-based tests to aid early TB diagnosis and subsequent positive impact on morbidity and mortality. Using LAM as a rule-in and treatment-monitoring tool may also show further potential.

Objectives SQ109, an asymmetrical diamine, is a novel anti-TB drug candidate. This first study in patients was done to determine safety, tolerability, pharmacokinetics and bacteriological effect of different doses of SQ109 alone and in combination with rifampicin when administered over 14 days. Patients and methods Smear-positive pulmonary TB patients were randomized into six groups of 15 to receive once-daily oral treatment with 75, 150 or 300 mg of SQ109, rifampicin (10 mg/kg body weight), rifampicin plus 150 mg of SQ109, or rifampicin plus 300 mg of SQ109 for 14 days. Patients were hospitalized for supervised treatment, regular clinical, biochemical and electrocardiographic safety assessments, pharmacokinetic profiling and daily overnight sputum collection. Results SQ109 was safe and generally well tolerated. Mild to moderate dose-dependent gastrointestinal complaints were the most frequent adverse events. No relevant QT prolongation was noted. Maximum SQ109 plasma concentrations were lower than MICs. Exposure to SQ109 (AUC0–24) increased by drug accumulation upon repeated administration in the SQ109 monotherapy groups. Co-administration of SQ109 150 mg with rifampicin resulted in decreasing SQ109 exposures from day 1 to day 14. A higher (300 mg) dose of SQ109 largely outweighed the evolving inductive effect of rifampicin. The daily fall in log cfu/mL of sputum (95% CI) was 0.093 (0.126–0.059) with rifampicin, 0.133 (0.166–0.100) with rifampicin plus 150 mg of SQ109 and 0.089 (0.121–0.057) with rifampicin plus 300 mg of SQ109. Treatments with SQ109 alone showed no significant activity. Conclusions SQ109 alone or with rifampicin was safe over 14 days. Upon co-administration with rifampicin, 300 mg of SQ109 yielded a higher exposure than the 150 mg dose. SQ109 did not appear to be active alone or to enhance the activity of rifampicin during the 14 days of treatment.

Setting: Greater Banjul area of The Gambia. Objectives: To evaluate uptake, adherence and completion of treatment among tuberculosis (TB) exposed children in The Gambia when isoniazid preventive treatment (IPT) is delivered at home Design: Child (age

BackgroundChildren account for an estimated 1 million new cases of TB every year, representing roughly 7% of the total disease burden. Every year, around 2 09 000 children die from TB, half of those cases are in Africa. The main issue continues to be timely and accurate diagnosis, as treatment outcomes – even in the case of drug resistance – are significantly better than in adults.Clinical diagnosis in the absence of laboratory confirmation is hampered by non-specificity of symptoms. Diagnostics validation studies in children are difficult – in most studies, very few of the symptomatic children achieved microbiological disease confirmation, resulting in imprecise estimates for test sensitivity.Design/methodsWith the RaPaed TB study funded by EDCTP, we are preparing an improved diagnostic validation study design to improve on the traditional approach of a single-gate, double diagnostic study in the target population. The project will evaluate multiple new tests on the same patients, to determine algorithms of screening and confirmatory tests. Most novel tests in this study use non-sputum samples and are therefore more suitable for children.Allocation of patients to standardised groups will follow the recommendations of the NIH-convened consensus panel on case definitions of paediatric TB diagnostic studies. Using an endpoint review committee will allow blinded review of those new-positive cases, plus matched controls, and determine their likelihood of disease based on clinical data including follow-up, and X-ray. This will improve the quality of evaluation of false positive vs. true positive results of new tests and therefore improve the assessment of specificity.To improve on sensitivity assessment, the study includes partners with a high number of confirmed cases in past studies and plans to draw in cases of confirmed disease from other diagnostic facilities.ConclusionThis improved methodology will lead to more meaningful and applicable results of diagnostic validation studies.

SETTING Mbeya, Tanzania. OBJECTIVE To develop a new liquid culture method to detect Mycobacterium tuberculosis complex (MTC) in sputum using 2,3-diphenyl-5-thienyl-(2)-tetrazolium (STC), the nitrate reductase assay (NRA) and p-nitrobenzoic acid (PNB). DESIGN Ninety-three sputum samples collected from 18 tuberculosis patients were decontaminated with N-acetyl-L-cysteine-sodium hydroxide using MGIT™ 960 and in STC-NRA cultures, both in the presence and in the absence of PNB, an inhibitor of MTC growth. The reduction of STC by colour change indicated mycobacterial growth; NRA was then performed to confirm MTC. RESULTS STC-NRA culture was positive for acid-fast bacilli in 66/93 (71%) samples, of which 60/93 (64.5%) were identified as MTC-positive and 6/93 (6.5%) as indeterminate mycobacteria. MGIT indicated MTC in 59/93 (63.4%) cultures. Contamination was detected in 12/93 (13%) STC-NRA cultures vs. 29/93 (31.2%) MGIT cultures. The mean time to detection (TTD) of MTC using STC-NRA was 14 days and 7 days using MGIT. CONCLUSION The STC-NRA method is sensitive for the detection of MTC in sputum. TTD increased with duration of anti-tuberculosis treatment, highlighting the value of this method in monitoring treatment success. The method is simple and inexpensive and, unlike MGIT, does not require technical equipment. The preliminary performance characteristics of the method should be further evaluated in larger studies.

SummaryBackgroundAn accurate biomarker is urgently needed to monitor the response to treatment in patients with pulmonary tuberculosis. The Xpert MTB/RIF assay is a commercially available real-time PCR that can be used to detect Mycobacterium-tuberculosis-specific DNA sequences in sputum samples. We therefore evaluated this assay with serial sputum samples obtained over 26 weeks from patients undergoing treatment for tuberculosis.MethodsWe analysed sputum samples from 221 patients with smear-positive tuberculosis enrolled at two sites (Cape Town, South Africa, and Mbeya, Tanzania) of a multicentre randomised clinical trial REMoxTB of antituberculosis treatment on a weekly basis (weeks 0 to 8), then at weeks 12, 17, 22, and 26 after treatment initiation. The Xpert MTB/RIF results over time were compared with the results of standard smear microscopy and culture methods.FindingsWe obtained and analysed 2741 sputum samples from 221 patients. The reduction in positivity rates with Xpert MTB/RIF were slower than those with the standard methods. At week 8, positive results were obtained for 62 (29%) of 212 sputum samples with smear microscopy, 46 (26%) of 175 with solid culture (Löwenstein-Jensen medium), 77 (42%) of 183 with liquid culture (Bactec MGIT960 system), and 174 (84%) of 207 with Xpert MTB/RIF; at 26 weeks, positive results were obtained for ten (5%) of 199, four (3%) of 157, seven (4%) of 169, and 22 (27%) of 83 sputum samples, respectively. The reduction in detection of quantitative M tuberculosis DNA with Xpert MTB/RIF correlated with smear grades (ρ=–0·74; p

Rickettsioses caused by typhus group rickettsiae have been reported in various African regions. We conducted a cross-sectional survey of 1,227 participants from 9 different sites in the Mbeya region, Tanzania; overall seroprevalence of typhus group rickettsiae was 9.3%. Risk factors identified in multivariable analysis included low vegetation density and highway proximity.