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1.
PLOS Glob Public Health ; 3(1): e0000741, 2023.
Article in English | MEDLINE | ID: mdl-36963008

ABSTRACT

Over the past decade, there have been increasing reports of non-tuberculous mycobacteria (NTM) species being implicated in tuberculosis (TB) treatment failure or misdiagnosed as TB. Inadequate awareness of NTM pulmonary disease among healthcare workers (HCWs) may contribute to a low index of suspicion for patients presenting to their hospitals. In this study, we assessed the awareness of NTM pulmonary disease (NTM-PD) among front desk HCWs in Northern Tanzania. A cross-sectional descriptive survey was carried out among front desk HCWs in four administrative regions of Northern Tanzania. A standardized questionnaire was administered to consented participants from four clusters; clinicians, laboratory scientists, nurses, and pharmacists serving TB patients from Regional and District Health Facilities. Each participant was asked a set of questions, scored and the total score for each participant was determined. An awareness score was used to measure the level of awareness. The average score for all participants was estimated including the 95% confidence interval (CI). The overall awareness score was 24.1%, 95% CI 22.0-26.2%. History of training, experience in TB care, level of health facilities, age group, and setting were found to be statistically associated with the level of awareness of study participants. More than two-thirds (67%) of participants believe that pulmonary NTM and TB are clinically similar and 60% are not aware that AFB Microscopy cannot distinguish between the two. Only 13% of participants could mention at least one risk factor for NTM pulmonary disease. The level of awareness of NTM pulmonary disease was poor among HCWs in the surveyed TB clinics. National TB Programs are advised to include a topic on NTM in various on-job TB training packages for HCWs.

2.
Trop Med Int Health ; 27(10): 891-901, 2022 10.
Article in English | MEDLINE | ID: mdl-36089572

ABSTRACT

OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.


Subject(s)
Extensively Drug-Resistant Tuberculosis , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Cross-Sectional Studies , Ethambutol , Extensively Drug-Resistant Tuberculosis/diagnosis , Extensively Drug-Resistant Tuberculosis/drug therapy , Extensively Drug-Resistant Tuberculosis/microbiology , Humans , Isoniazid/therapeutic use , Microbial Sensitivity Tests , Rifampin/therapeutic use , Streptomycin/therapeutic use , Tanzania/epidemiology , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/epidemiology , Tuberculosis, Multidrug-Resistant/microbiology
3.
BMC Genomics ; 23(1): 561, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35931954

ABSTRACT

BACKGROUND: Mycobacterium tuberculosis presents several lineages each with distinct characteristics of evolutionary status, transmissibility, drug resistance, host interaction, latency, and vaccine efficacy. Whole genome sequencing (WGS) has emerged as a new diagnostic tool to reliably inform the occurrence of phylogenetic lineages of Mycobacterium tuberculosis and examine their relationship with patient demographic characteristics and multidrug-resistance development. METHODS: 191 Mycobacterium tuberculosis isolates obtained from a 2017/2018 Tanzanian drug resistance survey were sequenced on the Illumina Miseq platform at Supranational Tuberculosis Reference Laboratory in Uganda. Obtained fast-q files were imported into tools for resistance profiling and lineage inference (Kvarq v0.12.2, Mykrobe v0.8.1 and TBprofiler v3.0.5). Additionally for phylogenetic tree construction, RaxML-NG v1.0.3(25) was used to generate a maximum likelihood phylogeny with 800 bootstrap replicates. The resulting trees were plotted, annotated and visualized using ggtree v2.0.4 RESULTS: Most [172(90.0%)] of the isolates were from newly treated Pulmonary TB patients. Coinfection with HIV was observed in 33(17.3%) TB patients. Of the 191 isolates, 22(11.5%) were resistant to one or more commonly used first line anti-TB drugs (FLD), 9(4.7%) isolates were MDR-TB while 3(1.6%) were resistant to all the drugs. Of the 24 isolates with any resistance conferring mutations, 13(54.2%) and 10(41.6%) had mutations in genes associated with resistance to INH and RIF respectively. The findings also show four major lineages i.e. Lineage 3[81 (42.4%)], followed by Lineage 4 [74 (38.7%)], the Lineage 1 [23 (12.0%)] and Lineages 2 [13 (6.8%)] circulaing in Tanzania. CONCLUSION: The findings in this study show that Lineage 3 is the most prevalent lineage in Tanzania whereas drug resistant mutations were more frequent among isolates that belonged to Lineage 4.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Demography , Drug Resistance, Multiple, Bacterial/genetics , Genotype , Humans , Microbial Sensitivity Tests , Mutation , Phylogeny , Tanzania/epidemiology , Tuberculosis/microbiology , Tuberculosis, Multidrug-Resistant/drug therapy
4.
BMC Infect Dis ; 20(1): 594, 2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32787869

ABSTRACT

BACKGROUND: Implementation of an effective Tuberculosis Routine Surveillance System in low-income countries like Tanzania is problematic, despite being an essential tool for the detection and effective monitoring of drug resistant tuberculosis. Long delays in specimen transportation from the facilities to reference laboratory and results dissemination back to the health facilities, result in poor patient management, particularly where multidrug-resistant tuberculosis disease is present. METHODS: Following a detailed qualitative study, a pilot intervention of a revised Tuberculosis Routine Surveillance System was implemented in Mwanza region, Tanzania. This included the use of rapid molecular methods for the detection of both tuberculosis and drug resistance using Xpert MTB/RIF in some Mwanza sites, the use of Xpert MTB/RIF and Line Probe Assay at the Central Tuberculosis Reference Laboratory, a revised communication strategy and interventions to address the issue of poor form completion. A before and after comparison of the intervention on the number of drug resistant tuberculosis cases identified and the time taken for results feedback to the requesting site was reported. RESULTS: The revised system for previously treated cases tested at the Central Reference Laboratory was able to obtain the following findings; the number of cases tested increased from 75 in 2016 to 185 in 2017. The times for specimen transportation from health facilities to the reference laboratory were reduced by 22% (from 9 to 7 days). The median time for the district to receive results was reduced by 36% (from 11 to 7 days). Overall the number of drug resistant tuberculosis cases starting treatment increased by 67% (from 12 to 20). CONCLUSION: Detection of drug resistance could significantly be enhanced, and delays reduced by introduction of new technologies and improved routine surveillance system, including better communication using mobile applications such as 'WhatsApp' and close follow-ups. A larger scale study is now merited to ascertain if these benefits are robust across different contexts.


Subject(s)
Delayed Diagnosis/prevention & control , Diagnostic Tests, Routine/methods , Epidemiological Monitoring , Mycobacterium tuberculosis/genetics , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/epidemiology , Antibiotics, Antitubercular/therapeutic use , Communication , Drug Resistance, Multiple, Bacterial , Health Facilities , Humans , Laboratories , Mycobacterium tuberculosis/isolation & purification , Nucleic Acid Amplification Techniques/methods , Pilot Projects , Prospective Studies , Qualitative Research , Rifampin/therapeutic use , Specimen Handling/methods , Tanzania/epidemiology , Tuberculosis, Multidrug-Resistant/drug therapy
5.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Article in English | MEDLINE | ID: mdl-32718966

ABSTRACT

We analyzed 312 drug-resistant genomes of Mycobacterium tuberculosis isolates collected from HIV-coinfected and HIV-negative TB patients from nine countries with a high tuberculosis burden. We found that rifampicin-resistant M. tuberculosis strains isolated from HIV-coinfected patients carried disproportionally more resistance-conferring mutations in rpoB that are associated with a low fitness in the absence of the drug, suggesting these low-fitness rpoB variants can thrive in the context of reduced host immunity.


Subject(s)
HIV Infections , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Antitubercular Agents , Bacterial Proteins/genetics , DNA-Directed RNA Polymerases/genetics , HIV Infections/complications , HIV Infections/drug therapy , Humans , Microbial Sensitivity Tests , Mutation , Mycobacterium tuberculosis/genetics , Rifampin
6.
Liver Int ; 40(3): 514-521, 2020 03.
Article in English | MEDLINE | ID: mdl-31778282

ABSTRACT

BACKGROUND: Although novel hepatitis C virus (HCV) RNA point-of-care technology has the potential to enhance the diagnosis in resource-limited settings, very little real-world validation of their utility exists. We evaluate the performance of HCV RNA quantification using the Xpert® HCV viral load Fingerstick assay (Xpert® HCV VL Fingerstick assay) as compared to the World Health Organisation pre-qualified plasma Xpert® HCV VL assay among people who inject drugs (PWID) attending an opioid agonist therapy (OAT) clinic in Dar-es-Salaam, Tanzania. METHODS: Between December 2018 and February 2019, consecutive HCV seropositive PWID attending the OAT clinic provided paired venous and Fingerstick samples for HCV RNA quantification. These were processed onsite using the GeneXpert® platform located at the Central tuberculosis reference laboratory. RESULTS: A total of 208 out of 220 anti-HCV-positive participants recruited (94.5%) had a valid Xpert® HCV VL result available; 126 (61%; 95% CI 53.8-67.0) had detectable and quantifiable HCV RNA. About 188 (85%) participants had paired plasma and Fingerstick whole blood samples; the sensitivity and specificity for the quantification of HCV RNA levels were 99.1% and 98.7% respectively. There was an excellent correlation (R2  = .95) and concordance (mean difference 0.13 IU/mL, (95% CI -0.9 to 0.16 IU/mL) in HCV RNA levels between plasma samples and Fingerstick samples. CONCLUSION: This study found excellent performance of the Xpert® HCV VL Fingerstick assay for HCV RNA detection and quantification in an African-field setting. Its clinical utility represents an important watershed in overcoming existing challenges to HCV diagnosis, which should play a crucial role in HCV elimination in Africa.


Subject(s)
Hepatitis C , Pharmaceutical Preparations , Hepacivirus/genetics , Hepatitis C/diagnosis , Humans , RNA, Viral , Sensitivity and Specificity , Tanzania , Viral Load
7.
PLoS One ; 14(4): e0206334, 2019.
Article in English | MEDLINE | ID: mdl-30978186

ABSTRACT

BACKGROUND: Human tuberculosis (TB) is caused by seven phylogenetic lineages of the Mycobacterium tuberculosis complex (MTBC), Lineage 1-7. Recent advances in rapid genotyping of MTBC based on single nucleotide polymorphisms (SNP), allow for phylogenetically robust strain classification, paving the way for defining genotype-phenotype relationships in clinical settings. Such studies have revealed that, in addition to host and environmental factors, strain variation in the MTBC influences the outcome of TB infection and disease. In Tanzania, such molecular epidemiological studies of TB however are scarce in spite of a high TB burden. METHODS AND FINDINGS: Here we used SNP-typing to characterize a nationwide collection of 2,039 MTBC clinical isolates representative of 1.6% of all new and retreatment TB cases notified in Tanzania during 2012 and 2013. Four lineages, namely Lineage 1-4 were identified within the study population. The distribution and frequency of these lineages varied across regions but overall, Lineage 4 was the most frequent (n = 866, 42.5%), followed by Lineage 3 (n = 681, 33.4%) and 1 (n = 336, 16.5%), with Lineage 2 being the least frequent (n = 92, 4.5%). We found Lineage 2 to be independently associated with female sex (adjusted odds ratio [aOR] 2.14; 95% confidence interval [95% CI] 1.31 - 3.50, p = 0.002) and retreatment cases (aOR 1.67; 95% CI 0.95 - 2.84, p = 0. 065) in the study population. We found no associations between MTBC lineage and patient age or HIV status. Our sublineage typing based on spacer oligotyping on a subset of Lineage 1, 3 and 4 strains revealed the presence of mainly EAI, CAS and LAM families. Finally, we detected low levels of multidrug resistant isolates among a subset of 144 retreatment cases. CONCLUSIONS: This study provides novel insights into the MTBC lineages and the possible influence of pathogen-related factors on the TB epidemic in Tanzania.


Subject(s)
Mycobacterium tuberculosis/genetics , Phylogeny , Polymorphism, Single Nucleotide , Tuberculosis, Pulmonary/genetics , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Tanzania/epidemiology , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/microbiology
8.
PLoS One ; 14(2): e0212421, 2019.
Article in English | MEDLINE | ID: mdl-30794620

ABSTRACT

BACKGROUND: Routine surveillance is required to monitor the performance of tuberculosis diagnostic programme and is essential for the rapid detection of drug resistance. The main objective of this study was to explore the effectiveness and stakeholder perception of the current routine surveillance system for previously treated tuberculosis cases in Tanzania with a view to identify interventions to improve and accelerate positive patient outcomes. METHODS: A study using quantitative and qualitative methods of data collection including in-depth interviews and focus group discussions with health care service providers was conducted in four regions. Quantitative data were extracted from the routine databases to assess performance. RESULTS: Quantitative findings from 2011 to 2013 showed 2,750 specimens from previously treated TB cases were received at the reference laboratory. The number increased year on year, but even in the most recent year was only 61% of that expected. The median and interquartile range of turnaround time in days from specimen reception to results reported for smear microscopy, culture and drug susceptibility testing were 1(1, 1), 61(43, 71) and 129(72, 170) respectively. Contaminated specimens were reported in 3.6% of cases. The qualitative analysis showed the system of sending specimens using postal services was seen to be efficient by participants. However, there were many challenges and significant delays in specimens reaching the reference laboratory associated with lack of funds to transfer specimens, weak form completion, inadequate training and poor supervision. These all adversely affected the implementation of the routine surveillance system. CONCLUSIONS: Many issues limit the effectiveness of the routine surveillance system in Tanzania. Priority areas for strengthening are; specimen transportation, supervision and availability of commodities. A pilot study of a revised routine surveillance system that takes into account the observations from this study alongside improved access to drug susceptibility testing using Xpert MTB/RIF should be considered.


Subject(s)
Epidemiological Monitoring , Tuberculosis, Multidrug-Resistant/epidemiology , Attitude of Health Personnel , Cross-Sectional Studies , Female , Focus Groups , Humans , Male , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/isolation & purification , Perception , Stakeholder Participation , Tanzania/epidemiology , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/microbiology
9.
BMC Infect Dis ; 17(1): 542, 2017 08 04.
Article in English | MEDLINE | ID: mdl-28778186

ABSTRACT

BACKGROUND: Culture contamination with environmental bacteria is a major challenge in tuberculosis (TB) laboratories in hot and humid climate zones. We studied the effect of cetylpyridinium chloride (CPC) preservation on culture results and performance of Xpert MTB/RIF. METHODS: Consecutive sputum samples from microscopy smear-positive TB patients were collected. Two-hundred samples were equally split in two aliquots, one aliquot was treated with CPC and stored at ambient temperature for 7 days. The second aliquot was immediately processed. Samples were decontaminated for 20, 15 or 10 min, and subsequently cultured on Löwenstein-Jensen medium. Furthermore, 50 samples were stored for 7, 14 and 21 days, and 100 CPC-pretreated samples tested by Xpert MTB/RIF. RESULTS: CPC pretreated samples showed a higher culture yield compared to non-treated sputum samples across all decontamination times: 94% vs. 73% at 10 min (p = 0.01), 94% vs. 64% at 15 min (p = 0.004), and 90% vs. 52% at 20 min (p < 0.001). The quantitative culture grading was consistently higher in CPC treated compared to non-CPC treated samples. The proportion of contaminated cultures was lower in CPC pretreated samples across all decontamination times (range 2-6%) compared to non-CPC treated samples (15-16%). For storage times of CPC treated samples of 7, 14, and 21 days, 84, 86, and 84% of the respective cultures were positive. Of 91 CPC treated samples with a positive culture, 90 were also Xpert MTB/RIF positive. CONCLUSIONS: CPC increases culture yield, decreases the proportion of contamination, and does not alter the performance of Xpert MTB/RIF.


Subject(s)
Bacteriological Techniques/methods , Cetylpyridinium/chemistry , Mycobacterium tuberculosis/genetics , Specimen Handling/methods , Sputum/microbiology , Developing Countries , Humans , Microscopy/methods , Mycobacterium tuberculosis/pathogenicity , Nucleic Acid Amplification Techniques/methods , Sputum/chemistry , Tanzania , Tuberculosis, Pulmonary/microbiology
10.
J Am Med Inform Assoc ; 23(5): 916-23, 2016 09.
Article in English | MEDLINE | ID: mdl-26911813

ABSTRACT

OBJECTIVE: A software tool is developed to facilitate data entry and to monitor research projects in under-resourced countries in real-time. METHODS: The eManagement tool "odk_planner" is written in the scripting languages PHP and Python. The odk_planner is lightweight and uses minimal internet resources. It was designed to be used with the open source software Open Data Kit (ODK). The users can easily configure odk_planner to meet their needs, and the online interface displays data collected from ODK forms in a graphically informative way. The odk_planner also allows users to upload pictures and laboratory results and sends text messages automatically. User-defined access rights protect data and privacy. RESULTS: We present examples from four field applications in Tanzania successfully using the eManagement tool: 1) clinical trial; 2) longitudinal Tuberculosis (TB) Cohort Study with a complex visit schedule, where it was used to graphically display missing case report forms, upload digitalized X-rays, and send text message reminders to patients; 3) intervention study to improve TB case detection, carried out at pharmacies: a tablet-based electronic referral system monitored referred patients, and sent automated messages to remind pharmacy clients to visit a TB Clinic; and 4) TB retreatment case monitoring designed to improve drug resistance surveillance: clinicians at four public TB clinics and lab technicians at the TB reference laboratory used a smartphone-based application that tracked sputum samples, and collected clinical and laboratory data. CONCLUSIONS: The user friendly, open source odk_planner is a simple, but multi-functional, Web-based eManagement tool with add-ons that helps researchers conduct studies in under-resourced countries.


Subject(s)
Biomedical Research/organization & administration , Software , Clinical Trials as Topic , Cohort Studies , Database Management Systems , Developing Countries , Humans , Internet , Tanzania , Tuberculosis/diagnosis , Tuberculosis/therapy
11.
PLoS One ; 10(9): e0138413, 2015.
Article in English | MEDLINE | ID: mdl-26418678

ABSTRACT

OBJECTIVE: We examined the effect of an instructional video about the production of diagnostic sputum on case detection of tuberculosis (TB), and evaluated the acceptance of the video. TRIAL DESIGN: Randomized controlled trial. METHODS: We prepared a culturally adapted instructional video for sputum submission. We analyzed 200 presumptive TB cases coughing for more than two weeks who attended the outpatient department of the governmental Municipal Hospital in Mwananyamala (Dar es Salaam, Tanzania). They were randomly assigned to either receive instructions on sputum submission using the video before submission (intervention group, n = 100) or standard of care (control group, n = 100). Sputum samples were examined for volume, quality and presence of acid-fast bacilli by experienced laboratory technicians blinded to study groups. RESULTS: Median age was 39.1 years (interquartile range 37.0-50.0); 94 (47%) were females, 106 (53%) were males, and 49 (24.5%) were HIV-infected. We found that the instructional video intervention was associated with detection of a higher proportion of microscopically confirmed cases (56%, 95% confidence interval [95% CI] 45.7-65.9%, sputum smear positive patients in the intervention group versus 23%, 95% CI 15.2-32.5%, in the control group, p <0.0001), an increase in volume of specimen defined as a volume ≥3ml (78%, 95% CI 68.6-85.7%, versus 45%, 95% CI 35.0-55.3%, p <0.0001), and specimens less likely to be salivary (14%, 95% CI 7.9-22.4%, versus 39%, 95% CI 29.4-49.3%, p = 0.0001). Older age, but not the HIV status or sex, modified the effectiveness of the intervention by improving it positively. When asked how well the video instructions were understood, the majority of patients in the intervention group reported to have understood the video instructions well (97%). Most of the patients thought the video would be useful in the cultural setting of Tanzania (92%). CONCLUSIONS: Sputum submission instructional videos increased the yield of tuberculosis cases through better quality of sputum samples. If confirmed in larger studies, instructional videos may have a substantial effect on the case yield using sputum microscopy and also molecular tests. This low-cost strategy should be considered as part of the efforts to control TB in resource-limited settings. TRIAL REGISTRATION: Pan African Clinical Trials Registry PACTR201504001098231.


Subject(s)
Mycobacterium tuberculosis/isolation & purification , Patient Education as Topic/methods , Sputum/microbiology , Tuberculosis, Pulmonary/diagnosis , Adult , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Tanzania , Tuberculosis, Pulmonary/microbiology
12.
Lancet Glob Health ; 2(10): e581-91, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25304634

ABSTRACT

BACKGROUND: Several promising new diagnostic methods and algorithms for tuberculosis have been endorsed by WHO. National tuberculosis programmes now face the decision on which methods to implement and where to place them in the diagnostic algorithm. METHODS: We used an integrated model to assess the effects of different algorithms of Xpert MTB/RIF and light-emitting diode (LED) fluorescence microscopy in Tanzania. To understand the effects of new diagnostics from the patient, health system, and population perspective, the model incorporated and linked a detailed operational component and a transmission component. The model was designed to represent the operational and epidemiological context of Tanzania and was used to compare the effects and cost-effectiveness of different diagnostic options. FINDINGS: Among the diagnostic options considered, we identified three strategies as cost effective in Tanzania. Full scale-up of Xpert would have the greatest population-level effect with the highest incremental cost: 346 000 disability-adjusted life-years (DALYs) averted with an additional cost of US$36·9 million over 10 years. The incremental cost-effectiveness ratio (ICER) of Xpert scale-up ($169 per DALY averted, 95% credible interval [CrI] 104-265) is below the willingness-to-pay threshold ($599) for Tanzania. Same-day LED fluorescence microscopy is the next most effective strategy with an ICER of $45 (95% CrI 25-74), followed by LED fluorescence microscopy with an ICER of $29 (6-59). Compared with same-day LED fluorescence microscopy and Xpert full rollout, targeted use of Xpert in presumptive tuberculosis cases with HIV infection, either as an initial diagnostic test or as a follow-on test to microscopy, would produce DALY gains at a higher incremental cost and therefore is dominated in the context of Tanzania. INTERPRETATION: For Tanzania, this integrated modelling approach predicts that full rollout of Xpert is a cost-effective option for tuberculosis diagnosis and has the potential to substantially reduce the national tuberculosis burden. It also estimates the substantial level of funding that will need to be mobilised to translate this into clinical practice. This approach could be adapted and replicated in other developing countries to inform rational health policy formulation.


Subject(s)
Microscopy, Fluorescence/economics , Microscopy, Fluorescence/instrumentation , Sputum/microbiology , Tuberculosis/diagnosis , Algorithms , Antitubercular Agents/pharmacology , Cost-Benefit Analysis , Drug Resistance, Bacterial , Government Programs/economics , Humans , Models, Econometric , Rifampin/pharmacology , Tanzania , Time Factors
13.
Parasitology ; 141(14): 1795-802, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25035934

ABSTRACT

Research and innovation in the diagnosis of infectious and parasitic diseases has led to the development of several promising diagnostic tools, for example in malaria there is extensive literature concerning the use of rapid diagnostic tests. This means policymakers in many low and middle income countries need to make difficult decisions about which of the recommended tools and approaches to implement and scale-up. The test characteristics (e.g. sensitivity and specificity) of the tools alone are not a sufficient basis on which to make these decisions as policymakers need to also consider the best combination of tools, whether the new tools should complement or replace existing diagnostics and who should be tested. Diagnostic strategies need dovetailing to different epidemiology and structural resource constraints (e.g. existing diagnostic pathways, human resources and laboratory capacity). We propose operational modelling to assist with these complex decisions. Projections of patient, health system and cost impacts are essential and operational modelling of the relevant elements of the health system could provide these projections and support rational decisions. We demonstrate how the technique of operational modelling applied in the developing world to support decisions on diagnostics for tuberculosis, could in a parallel way, provide useful insights to support implementation of appropriate diagnostic innovations for parasitic diseases.


Subject(s)
Diagnostic Tests, Routine/methods , Parasites/isolation & purification , Parasitic Diseases/diagnosis , Tuberculosis/diagnosis , Animals , Computer Simulation , Decision Support Techniques , Diagnostic Tests, Routine/economics , Health Care Costs , Humans , Operations Research , Parasitic Diseases/economics , Parasitic Diseases/therapy , Policy Making , Sensitivity and Specificity , Tuberculosis/economics , Tuberculosis/therapy
14.
Lancet Infect Dis ; 14(7): 563-71, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24810491

ABSTRACT

BACKGROUND: WHO guidelines recommend early initiation of antiretroviral therapy (ART) irrespective of CD4 cell count for all patients with tuberculosis who also have HIV, but evidence supporting this approach is poor quality. We assessed the effect of timing of ART initiation on tuberculosis treatment outcomes for HIV-positive patients with CD4 counts of 220 cells per µL or more. METHODS: We did this randomised, placebo-controlled trial between Jan 1, 2008, and April 31, 2013 at 26 treatment centres in South Africa, Tanzania, Uganda, and Zambia. We enrolled HIV-positive patients with culture-confirmed tuberculosis who had tolerated 2 weeks of tuberculosis short course chemotherapy. Participants were randomly allocated (1:1) to early ART (starting after 2 weeks of tuberculosis treatment) or delayed ART (placebo, then starting ART at the end of 6 months of tuberculosis treatment). Randomisation was computer generated, with permuted blocks of size eight, and stratified by CD4 count (220-349 cells per µL vs ≥350 cells per µL). Patients and investigators were masked to treatment allocation until completion of 6-months' tuberculosis treatment, after which the study was open label. The primary endpoint was a composite of failure of tuberculosis treatment, tuberculosis recurrence, and death within 12 months of starting tuberculosis treatment in the modified intention-to-treat population. Secondary endpoints included mortality. The study is registered with controlled-trials.com (ISRCTN77861053). FINDINGS: We screened 13,588 patients and enrolled 1675: 834 assigned early ART, 841 delayed ART. The primary endpoint was reached by 65 (8·5%) of 767 patients in the early ART group versus 71 (9·2%) of 771 in the delayed ART group (relative risk [RR] 0·91, 95% CI 0·64-1·30; p=0·9). Of patients with a CD4 cell count of 220-349 cells per µL, 26 (7·9%) of 331 patients versus 33 (9·6%) of 342 reached the primary endpoint (RR 0·80, 95% CI 0·46-1·39; p=0·6). For those with 350 cells per µL or more, 39 (8·9%) of 436 versus 38 (8·9%) of 429 reached the primary endpoint (RR 1·01, 95% CI 0·63-1·62; p=0·4). Mortality did not differ significantly between treatment groups (RR 1·4, 95% CI 0·8-2·3; p=0·23). Grade 3 and 4 adverse events occurred in 149 (18%) of 834 patients assigned early ART versus 174 (21%) of 841 assigned delayed ART (p=0·37). 87 (10%) of 834 versus 84 (10%) of 841 had immune reconstitution inflammatory syndrome (p=0·56). INTERPRETATION: ART can be delayed until after completion of 6 months of tuberculosis treatment for HIV-positive patients with tuberculosis who have CD4 cell counts greater than 220 cells per µL. WHO guidelines should be updated accordingly. FUNDING: USAID, Zambia Ministry of Health, Tanzania Commission for Science and Technology, WHO-TDR.


Subject(s)
Anti-HIV Agents/administration & dosage , Antiretroviral Therapy, Highly Active/methods , HIV Infections/drug therapy , Tuberculosis, Pulmonary/drug therapy , Adult , CD4 Lymphocyte Count/methods , Drug Administration Schedule , Female , HIV Infections/immunology , HIV Infections/microbiology , HIV Seropositivity/drug therapy , HIV Seropositivity/microbiology , Humans , Male , Prospective Studies , Tuberculosis, Pulmonary/immunology , Tuberculosis, Pulmonary/virology
15.
J Infect Dev Ctries ; 7(9): 676-9, 2013 Sep 16.
Article in English | MEDLINE | ID: mdl-24042104

ABSTRACT

INTRODUCTION: Diagnosing tuberculosis in low-resource settings mostly relies on sputum smear microscopy. Improvement through capacity building is a priority. This project aimed to strengthen tuberculosis diagnosis at an intermediate level laboratory. METHODOLOGY: The Italian National Institute for Infectious Diseases and the Italian Development Cooperation closely collaborated with regional and national institutions and reference laboratories to provide laboratory setup, equipment and reagents, personnel training, and the implementation of culture and quality assessment programs at Dodoma Regional Hospital, Dodoma, Tanzania. RESULTS: Microscopy sensitivity was increased, personnel were trained, and culture techniques and quality assessment programs were introduced. CONCLUSIONS: Implementing tuberculosis diagnosis in resource-constrained settings is feasible and represents a basis for further strengthening.


Subject(s)
Clinical Laboratory Services/organization & administration , Clinical Laboratory Techniques/methods , Tuberculosis/diagnosis , Clinical Laboratory Services/economics , Clinical Laboratory Techniques/economics , Developing Countries , Humans , Tanzania
16.
Health Care Manag Sci ; 15(3): 239-53, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22674467

ABSTRACT

The introduction and scale-up of new tools for the diagnosis of Tuberculosis (TB) in developing countries has the potential to make a huge difference to the lives of millions of people living in poverty. To achieve this, policy makers need the information to make the right decisions about which new tools to implement and where in the diagnostic algorithm to apply them most effectively. These decisions are difficult as the new tools are often expensive to implement and use, and the health system and patient impacts uncertain, particularly in developing countries where there is a high burden of TB. The authors demonstrate that a discrete event simulation model could play a significant part in improving and informing these decisions. The feasibility of linking the discrete event simulation to a dynamic epidemiology model is also explored in order to take account of longer term impacts on the incidence of TB. Results from two diagnostic districts in Tanzania are used to illustrate how the approach could be used to improve decisions.


Subject(s)
Decision Making , Developing Countries , Health Policy , Models, Theoretical , Tuberculosis, Pulmonary/diagnosis , Algorithms , Cost-Benefit Analysis , Critical Pathways , Delivery of Health Care/organization & administration , Humans , Policy Making , Sputum/microbiology , Time Factors , Tuberculosis, Pulmonary/economics , Tuberculosis, Pulmonary/epidemiology
17.
BMC Public Health ; 8: 427, 2008 Dec 30.
Article in English | MEDLINE | ID: mdl-19116022

ABSTRACT

BACKGROUND: A drug resistance survey is an essential public health management tool for evaluating and improving the performance of National Tuberculosis control programmes. The current manuscript describes the implementation of the first national drug resistance survey in Tanzania. METHODS: Description of the implementation process of a national anti-tuberculosis drug resistance survey in Tanzania, in relation to the study protocol and Standard Operating Procedures. RESULTS: Factors contributing positively to the implementation of the survey were a continuous commitment of the key stakeholders, the existence of a well organized National Tuberculosis Programme, and a detailed design of cluster-specific arrangements for rapid sputum transportation. Factors contributing negatively to the implementation were a long delay between training and actual survey activities, limited monitoring of activities, and an unclear design of the data capture forms leading to difficulties in form-filling. CONCLUSION: Careful preparation of the survey, timing of planned activities, a strong emphasis on data capture tools and data management, and timely supervision are essential for a proper implementation of a national drug resistance survey.


Subject(s)
Antitubercular Agents/pharmacology , Communicable Disease Control/standards , Health Plan Implementation/organization & administration , Health Surveys , National Health Programs/organization & administration , Tuberculosis, Multidrug-Resistant/epidemiology , Antitubercular Agents/classification , Drug Resistance, Bacterial , Humans , Information Management , Mycobacterium tuberculosis/drug effects , Program Development , Program Evaluation , Sputum/microbiology , Tanzania/epidemiology , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/prevention & control
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