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1 Thank you for viewing this presentation.
We would like to remind you that this material is the property of the author. It is provided to you by the ERS for your personal use only, as submitted by the author. 2012 by the author

2 From traditional bacteriology to rapid molecular methods: the revolution is going on (September 2012; Vienna) Keertan Dheda, MB.BCh, FCP(SA), FCCP, PhD (Lond), FRCP (Lond) Professor and Head: Lung Infection and Immunity Unit Division of Pulmonology & UCT Lung Institute, Department of Medicine, Conflict of interest: none

3 1 in 100 South Africans have TB
“If TB and AIDS are a snake, then the head is in South Africa while the tail is quickly moving through other African countries… And if the head of the snake is in South Africa then the teeth are in Durban” Dr Aaron Motsaledi (SA minister of Health) World TB Day, 24 March 2011 1 in 100 South Africans have TB cases per annum (1000 new cases every day!)

4 Overview Epidemiology of DR-TB, TB control, and the unmet need for diagnostics Appreciating phenotype and sampling error and its implications NAATS: Gene Xpert MTB-RIF Hain MDR TB plus (including new version) Hain MDR TB sl Plex ID (combination of mass spec and NAAT) Newer and novel approaches: HRM assay MDR on a chip (array and microfuidics) Sequencing Lateral flow assays Summary and conclusions Whole bunch of diagnostic tests in the pipeline and many in development- I will focus predominantly on newer tools are are already available or imminently available to practising clinicians

5 What is the size of the problem globally?
Worldwide prevalent cases of MDR-TB in 2010 (5·4% of the 12 million prevalent cases) ( new cases; 3.4% of new cases and 20% of retreatment cases) WHO. Global TB Control XDR-TB: globally~ XDR-TB cases annually

6 MDR-TB in SA 80% of MDR-TB results from ongoing transmission
Streicher and Warren, Infect Gen Evol, 2011 In Khayelitsha, Cape Town, 81% of MDR-TB likely due to primary transmission Cox HS, PLoS One, 2010 Therefore any cost saving strategy that targets testing, only to those with risk factors, will miss a substantial number of cases and fail to supress on-going transmission Although MDR was initailly acquired…………

7 N= 46 isolates from the WC Genotyping and mutational analysis = 81% acquired resistance

8 N= 199 XDR-TB 60 to 70% of our MDR-TB cases are also smear negative so the better performance of Xpert in smear negative TB is gratifying

9 Major unmet diagnostic need
Only 7% MDR-TB reported and 1-2% actually treated to WHO standards Less than 2% of cases have available DST result Very few reference laboratories in the 22 high burden countries Need user-friendly rapid tools, preferably at point of care, given decentralised MDR treatment programmes

10 Approach to diagnosis Major problem is that DRTB cannot be diagnosed Visualise the bug- LED microscopy, various techniques to concentrate the bugs (AB, magnets, spin filters) Pai et al. Sem Resp Crit Care Med 2008

11 Approach to diagnosis and new technologies
Major problem is that takes several weeks, significant contamination rate, MOD suited to resource-poor settings but very labour intensive and cannot be sited at point of care Grow the bug- liquid culture, MODS Pai et al. Sem Resp Crit Care Med 2008

12 Diagnostic test impact
Patient Sample Diagnostic test Result Initiate treatment Maintain treatment Diagnostic only one element of DR-TB control

13 TB diagnosis and control in HIV-infected persons
~ 20% are sputum scarce 20% have extrapulmonary TB (paucibaciliary) ~ 30 to 40% are smear negative- often poor quality Smaller volume of sputum and lower concentration of M.tb Pulmonary infiltrates atypical or chest x-ray may be normal LOW CD4 count < 200 cells/ ml Have an extended length of stay before diagnosis is made and treatment is initiated Many patients die undiagnosed with TB 1st 2 points even in HIV uninfected persons Theron and Dheda, AJRCCM, 2011

14 Problem of sample aquisition
Even with tests like Xpert about 1/3 of TB will probably remain undiagnosed without additional interventions (sputum scarce PTB, undiagnosed fraction of smear negative TB, and EPTB) Sputum induction and bronchoscopy- only available in tertiary care facilities Any diagnostic test is dependent on acquiring a suitable sample

15 What is Xpert MTB/RIF? Xpert is an automated real-time PCR for the diagnosis of TB and genotypic rifampicin resistance WHO approved: frontline dx for individuals suspected of TB-HIV co-infection SA DoH has initiated the replacement of smear by Xpert for TB suspects Scott, PLoS Med, 2011

16 Boehme C, NEJM, 2010

17 C Boehme, FIND Diagnostics
Overlapping primers specific for the rpoB gene hotspot, if there is fidelity, probes bind to primers dissociated the dye ad the quencher resulting in fluouresence which can be measured and coresponds to a Ct value. Thus, the higher the amount of input DNA the lower the Ct value C Boehme, FIND Diagnostics

18 Gene Xpert (WHO endorsed)
Cost: R1003 (Path Care)- Jan 2012 R 80 per cartridge (excludes capital cost and labour) How good is it: Sensitivity= 97% in smear +ve and 70% in smear negative; Specificity = 99% User-friendly and quick- POC. Closed system. However, only R resistance (not I, FQ, Cap, Etham like Hain) Currently being rolled out in SA Tiered developing country price- R for the hardware (4 module machine and about R150 per cartridge

19 How does Xpert MTB/RIF perform?
Rif R Boehme et al, NEJM, 2010 (N= 1730); Boehme et al, Lancet, 2011 (n= 5000)

20 Gene Xpert (WHO endorsed)
Drawbacks: (i) Expensive. (iii) Negative test high rule-out value in uninfected but not HIV-infected persons. Theron and Dheda, AJRCCM, 2011 (iii) PPV for DR-TB locally is sub-optimal so may be overcalling DR-TB- new cartridge being trialled (G5).

21 Has already been rolled out in 12 clinics in Cape Town in the Klipfontein district (16 module Xpert machine at GP). 3 national phases. Phase 1 in the 1st quarter of each of the provinces (DH and day hospitals); phase 2 in quarter 3 (go to full capacity in phase 1 clinics and co-opt additional sites); phase 3- bigger centres Discordance between genotypic and phenotypic because samples used are different ie unprocessed vs processed (false-ve phenotypic if mixed strains and disproportionate killing on the R strain by NaOH because it is less fit or problem with mixing the drug or drug quality). False +ve phenotypic with contamination. False –ve genotypic as 5 % of mutations outside the rpoB gene hot spot False +genotypic with contamination (unusual with Xpert) VAN RIE AND WARREN MIXED INFECTION

22 HIV-infected persons: Studies from ARV clinic in CT (n= 468 patients)
If no sputum- 2 induced samples Otherwise 1 spot and 1 induced sample 10% of cases no samples could be obtained Lawn SD, PLoS Med, 2011

23 Studies from primary care TB clinics- Cape Town (n=480 with suspected TB)
Theron and Dheda, AJRCCM, 2011

24 NPV was 91·3% (389/426; 95% CI 88·3–93·6) in HIV-infected
Boehme C, Lancet, 2011 Multisite evaluation study Comment by Theron, Lancet, 2011 (letter) NPV was 91·3% (389/426; 95% CI 88·3–93·6) in HIV-infected versus 96·0% (748/779; 94·4–97·2;p<0·001) in the uninfected; the respective negative LRs were 0·18 (0·17–0·19) versus 0·09 (0·09–0·10). Thus, about one in ten people that have active tuberculosis will have a negative test result. No difference in sensitivity in HIV-infected and uninfected

25 Studies from primary care TB clinic- Johannesburg (n= 311 TB suspects)
Sensitivity in HIV-infected persons not significantly different from the CT study Only 73 culture pos patients vs 128 in the CT study vs 44 in RCT prelim data Scott and Stevens, PLoS Med, 2011

26 Xpert MTB/RIF research gaps Beyond diagnostic accuracy to patient outcomes
Early proof of concept studies Large scale evaluation studies: What is the diagnostic accuracy? Phased demonstration and implementation studies: What is the technical feasibility? What are the short-term patient outcomes? Diagnostic RCTs addressing long-term patient outcomes (morbidity, morality etc.) What impact will this technology have given that case finding is passive and that treatment compliance is poor……….and do we need integration with other measures to make this technology effective

27 Xpert RCT: Patient flow
Hypothesis: One sputum Xpert MTB/RIF performed at the point-of-treatment is feasible and will improve TB-related morbidity and patient-level costs in individuals suspected of TB who present to primary level clinics in Africa

28 TB-NEAT study- N= 508 participants in Durban and CT (of 600 participants) Xpert MTB/RIF sensitivity is significantly diminished in HIV infected vs. uninfected patients (p= )

29 What currently available approaches can be used if Xpert is negative?
Perform CXR (rule out test) Await culture Perform a second Xpert Refer for further investigation Hain not an option in smear negative persons Treat empirically for TB (commonest approach) Hain MDRplus good tool in smear positive- main drawback is poor efficacy in smear negatives and open system. Still useful as Xpert capacity is very limited, Xpert inconclusive, SL testing.

30 How should Xpert be integrated with existing diagnostic algorithms?
Assessed the diagnostic accuracy and/or cost-effectiveness of smear-microscopy, chest-radiography, IGRAs combined with a single Xpert-MTB/RIF assay in 480 patients with suspected TB Xpert negative- although CXR has poor rule-in value, it can reliably rule-out TB in approximately 1 in 4 of such cases. Theron and Dheda, Eur Resp J, 2011

31 What currently available approaches can be used if Xpert is negative?
Perform CXR (rule out test) Await culture Perform a second Xpert (10% increase yield in SM-ve) Refer for further investigation Hain not an option in smear negative persons Blood culture Treat empirically for TB (commonest approach) Hain MDRplus good tool in smear positive- main drawback is poor efficacy in smear negatives and open system. Still useful as Xpert capacity is very limited, Xpert inconclusive, SL testing.

32 Other applications of Xpert: Bacterial burden and infectiousness
Smear microscopy though a crude predictor of infectiousness it is used to risk stratify patients for isolation and contact tracing Theron, Peter and Dheda, AJRCCM, 2011

33 Bacterial burden and infectiousness
Evaluated CT values in 496 patients with suspected TB Xpert CT values have poor rule-in [cut-point ≤20.2; sensitivity 32.3%; specificity 97.1%] Moderately good rule-out value for smear positivity [NPV 80.0%]. Thus, 20% of individuals with CT values >31.8 were smear- positive patients erroneously ruled out as smear-negatives. But smear status a crude proxy of infectiousness and Xpert may also detect intact but dead bugs! Same considerations apply to disease monitoring in MDR patients Theron, Peter and Dheda, Clin Infect Dis, 2011 So relationship unclear

34 Urine-orientated approach in HIV-infected sputum-scarce persons?
Sputum-based diagnostic unhelpful in 20-30% HIV-infected patients 116/242 culture +ve patients (54/116 i.e. 48% SS or SN) 18% (20/116) of all culture +ve were sputum scarce In this group (using urine) sensitivity: Xpert % (95%CI: 22-61) LAM 58% (95%CI: 49-67) LAM and Xpert 68% (95%CI: 60-77) [better than either; p= 0.003] In 6/14 +ve urine cases, LAM was exclusively positive We investigated the sensitivity of urine-based methods (Xpert MTB/RIF, LAM strip test and LAM ELISA) in such patients. Methods: 281 HIV-infected hospitalised patients with clinically suspected TB provided a spot urine sample. The reference standard was culture positivity for Mycobacterium tuberculosis on ≥1 sputum or extra-pulmonary sample. MTB/RIF was performed using 1ml of both unprocessed and, when possible, concentrated urine. Each unconcentrated urine sample was also tested using the Clearview LAM ELISA and Alere LAM strip test. Results: 42% (116/242) of patients had culture-proven TB. 18% (20/54) were sputum scarce. In sputum-scarce patients, the sensitivity of urine MTB/RIF and LAM ELISA was 40% (95%CI: 22-61) and 58% (95%CI: 49-67), respectively. Urine MTB/RIF specificity was 98% (95%CI: ). Combined sensitivity of urine LAM ELISA and MTB/RIF was better than MTB/RIF or LAM strip tests alone [MTB/RIF and LAM: 68% (95%CI: 60-77) vs. either MTB/RIF or LAM strip: 48% (95%CI: 39-57), p=0.003]. Significant predictors of urine MTB/RIF positivity were CD4<50 cells/ml (p=0.001), elevated protein-to-creatinine ratio (p<0.001) and LAM ELISA positivity (p<0.001). Urine centrifugation and pelleting significantly increased the sensitivity of MTB/RIF over unprocessed urine in paired samples [42% (95%CI: 26-58) vs. 8% (95%CI: 0-16), p<0.001]. Urine MTB/RIF-generated CT values correlated poorly with markers of bacillary burden (smear grade and time-to-positivity). Conclusions: This preliminary study indicates that urine-based MTB/RIF, alone or in combination with LAM antigen detection, may potentially aid the diagnosis of TB in HIV-infected patients with advanced immunosuppression when sputum-based diagnosis is not possible. Concentration of urine prior to MTB/RIF-testing significantly improves sensitivity. Peter and Dheda, PLoS One, 2012

35 Urine diagnostics to target HIV-infected sputum-scarce persons
Urine centrifugation and pelleting improved performance of Xpert in paired samples compared to unprocessed urine (42 vs 8%; p= 0.003) Urine-orientated approach feasible when a sputum-based tests are not feasible We investigated the sensitivity of urine-based methods (Xpert MTB/RIF, LAM strip test and LAM ELISA) in such patients. Methods: 281 HIV-infected hospitalised patients with clinically suspected TB provided a spot urine sample. The reference standard was culture positivity for Mycobacterium tuberculosis on ≥1 sputum or extra-pulmonary sample. MTB/RIF was performed using 1ml of both unprocessed and, when possible, concentrated urine. Each unconcentrated urine sample was also tested using the Clearview LAM ELISA and Alere LAM strip test. Results: 42% (116/242) of patients had culture-proven TB. 18% (20/54) were sputum scarce. In sputum-scarce patients, the sensitivity of urine MTB/RIF and LAM ELISA was 40% (95%CI: 22-61) and 58% (95%CI: 49-67), respectively. Urine MTB/RIF specificity was 98% (95%CI: ). Combined sensitivity of urine LAM ELISA and MTB/RIF was better than MTB/RIF or LAM strip tests alone [MTB/RIF and LAM: 68% (95%CI: 60-77) vs. either MTB/RIF or LAM strip: 48% (95%CI: 39-57), p=0.003]. Significant predictors of urine MTB/RIF positivity were CD4<50 cells/ml (p=0.001), elevated protein-to-creatinine ratio (p<0.001) and LAM ELISA positivity (p<0.001). Urine centrifugation and pelleting significantly increased the sensitivity of MTB/RIF over unprocessed urine in paired samples [42% (95%CI: 26-58) vs. 8% (95%CI: 0-16), p<0.001]. Urine MTB/RIF-generated CT values correlated poorly with markers of bacillary burden (smear grade and time-to-positivity). Conclusions: This preliminary study indicates that urine-based MTB/RIF, alone or in combination with LAM antigen detection, may potentially aid the diagnosis of TB in HIV-infected patients with advanced immunosuppression when sputum-based diagnosis is not possible. Concentration of urine prior to MTB/RIF-testing significantly improves sensitivity. Peter and Dheda, PLoS One, 2012

36 DST: Line probe assay (Hain)
Hain Lifescience GenoType® MTBDRplus Clinical samples (sens, spec): Rif (99; 99%) INH (85; 99)% Smear positive samples Morgan M, BMC Infect Dis, 2005; Ling D, Eur Resp J, 2008 Barnard M, AJRCCM, 2008 …. …metaanalysis of 14 studies …....promising test if these assays are consistently accurate when clinical samples like sputum are used.

37 DST: Line probe assay (Hain, InnoLip A)
Hain MTBDRplus (version 2.0) In 104 smear-ve culture +ve sputum samples combined sensitivity (80%) and specificity (99%) Crudu V, J Clin Micro, 2012 Hain Lifescience GenoType® MTBDRplus Clinical samples (sens, spec): Rif (99; 99%) INH (85; 99)% Smear positive samples Morgan M, BMC Infect Dis, 2005; Ling D, Eur Resp J, 2008 Barnard M, AJRCCM, 2008 …. …metaanalysis of 14 studies …....promising test if these assays are consistently accurate when clinical samples like sputum are used.

38 DST: Line probe assay (Hain)
Hain MTBDRplus (version 2.0) In 104 smear-ve culture +ve sputum samples combined sensitivity (80%) and specificity (99%) R100 per test in public sector and R571 in private sector Crudu V, J Clin Micro, 2012

39 Hain MDR+ sl version- to be used when R resistance is noted
Hain MDR+ sl version- to be used when R resistance is noted. Rapid evaluation of drug-resistance for FQ, AG + capreomycin [SLID] and ethambutol

40 Hain MDR+ sl version- to be used when R resistance is noted
Hain MDR+ sl version- to be used when R resistance is noted. Rapid evaluation of drug-resistance for FQ, AG + capreomycin [SLID] and ethambutol Total 64 sputum samples ( 26 DR-TB)) FQ (89%; 8/9), AG/capreo (87%; 7/8), and ethambutol (39%; 10/26); 100% specificity Hilleman D, J Clin Micro, 2009 Miotto P, ERJ, 2012 (10 clinical samples resistant to SLIDS) Lancoma A, JCM, 2012 (52 clinical samples resistant to SLIDS)

41 Hain MDR+ sl version Total 64 sputum samples (26 DR-TB)
FQ (89%; 8/9), AG/capreo (87%; 7/8), and ethambutol (39%; 10/26); 100% specificity Hilleman D, J Clin Micro, 2009 Miotto P, ERJ, 2012 (10 clinical samples resistant to SLIDS) Lancoma A, JCM, 2012 (52 clinical samples resistant to SLIDS)

42 206 MDR or XDR culture isolates
Excellent sensitivity and spec in isolates Markedly cuts down on time to diagnosis if patient is culture +ve

43

44 OVERALL SENSITIVITY AND SPEC IN SMEAR +VE AND -VES
N= 158 sputum samples from patients with proven M and XDR-TB All patients were culture positive

45 TOTAL INDETERMINATES= 3.19%=
Smear positive Thus, MTBDRplus (version 2.0) very useful in smear +ve samples- make diagnosis of MDR immediately TOTAL INDETERMINATES= 3.19%= [9/19 (47.4%) indeterminate in scanty pos vs. 1/71 (0.01%) in 1+ to 3+ pos] If MTBDRplus or Xpert pos proceed to the Hain SL in smear positive cases TOTAL INDETERMINATES= 13%= [9/19 (47%) in scanty pos vs. 11/74 (15%) in 1+ to 3+ pos] Culture DST still required to clarify type of SLID resistance

46 In smear-ve samples 37% of SL were indeterminate
Smear negative MTBDR PLUS STILL EXCELLENT Sens and Spec IN SMEAR NEG SAMPLES but 39% of results indeterminate! In smear-ve samples 37% of SL were indeterminate Thus, only useful in smear +ve samples

47 Combined approaches: PCR and mass spec (alternative to Hain and Xpert for isolate ID and DST)
PCR for gene-specific mutations followed by R, I, E and FQ resistance; already commercially available

48 Why do we need new tests? Xpert is accurate & cost-effective but very costly (even at $10 per cartridge consume about 25% of SA NTP budget) - stable power supply - suited to centralised rather than decentralised use - in up to a third of cases diagnosis cannot be made (sputum scarce, EPTB, smear negative TB undiagnosed) Large burden of undiagnosed TB (cost and access) Lack of a cheap same day test (human aspect and poverty) Takes hours to get to the clinic, significant costs,

49 POC detection technologies
NAAT with visual real-time readout including HRM NAAT with lateral flow readout NAAT with calorimetric readout (including LAMP) NAAT with biosensor readout (electro-chemical detection, piezoelectric quartz crystal biosensors, magnetoeleastic biosensors) NAAT with SERS readout Biochip readouts for DR TB (currently not automated and uses DNA from isolates) Park H, JCM, 2006

50 Several new commercial platforms that lend themselves to POC NAAT detection are now available
The Liat Analyzer automates all nucleic acid testing (NAT) processes, including reagent preparation, target enrichment, inhibitor removal, nucleic acid extraction, amplification and real-time detection. The system refines nucleic acid testing to three simple steps: collecting a raw biological sample such as whole blood into a Liat Tube and capping the tube, scanning the tube's barcode, and inserting the tube into the Liat Analyzer. The analyzer automatically executes all the required assay steps without further operator intervention. The test is completed and interpreted results are reported in as little as 20 minutes on the analyzer’s built-in touch screen, allowing accurate results to be delivered immediately for better and timely clinical decision making.

51 Bio Cartis Integrates all the diagnostic steps needed to provide true sample-in to result-out functionality, providing a significantly shorter turnaround time than current MDx technologies while requiring minimal hands-on time and training. Biocartis’ Molecular Diagnostics Platform features proprietary sample preparation technology that is suitable for a wide range of fluid and solid samples such as blood, urine or (tumor) tissue. The platform can be used to simultaneously detect and quantify up to 30 molecular biomarkers in a single assay. This level of multiplexing is required for more complex assays in which multiple biomarkers need to be analyzed Others including Enigma, Idahotech,

52 TWISTDX http://www.twistdx.co.uk/products/twista/
TwistDx’s proprietary technology, RPA (Recombinase Polymerase Amplification), represents a complete revolution in DNA diagnostics, combining superiority in speed, portability and accessibility with exquisite sensitivity and specificity compared to other diagnostic testing systems now on the market. It is usable in nearly any setting, eliminating the need for a trained technician or laboratory environment. TwistDx’s RPA process employs enzymes, known as recombinases, which are capable of pairing oligonucleotide primers with homologous sequence in duplex DNA. Through this method, DNA synthesis is directed to defined points in a sample DNA. If the target sequence is indeed present, DNA amplification reaction is initiated; no other sample manipulation such as thermal or chemical melting is required. The reaction progresses rapidly and results in specific DNA amplification from just a few target copies to detectable levels typically within minutes. The entire reaction system is stable as a dried formulation and can be transported safely without refrigeration. RPA can be used to replace PCR (Polymerase Chain Reaction) in a variety of laboratory applications and end-users can design their own ultra-sensitive assays.

53 High resolution melt and PCR
Species-specific DNA rpoB-specific DNA mutations NAAT with real-time readout using melting curves of amplified DNA amplicons- high sensitivity and specificity for MDR-TB Ramirez MV, JCM, 2010 Yadav R, J App Micro, 2012

54 Gold nanopartcles for detection of SNPs for rifampicin resistance using calorimetric readout
Veigas B, Nanotech, 2010

55 Simplified NAAT: LAMP (loop mediated isothermal amplification)
Rapid (1 hour), isothermal, high through-put, clinical samples Feasible in high burden settings (hospital or central laboratories) Sens in sputum smear negative TB 49% Limited data in HIV+ Cheaper Cannot multiplex Feasibility of this test was established Boehme CC, J Clin Micro, 2007

56 USTAR- RPA $300

57 Best Cassette- detection platform
The BioHelix® Express Strip (BESt™) Cassette is a novel, disposable, self-contained Amplicon Detection Device. It is designed for instrument-free, cross-contamination-proof detection of amplicons derived from HDA, PCR, and other nucleic amplification reactions. Features: Cross contamination proof - Detection takes place in an enclosed, disposable cassette. Sensitive - More sensitive than gel-based detection methods. Fast - Takes less than one minute to prepare and results are viewable in 5-10 minutes. detects two amplicons.

58 Lateral flow readout for NAAT products

59 EC detection platform for NAAT products
Gonzales- Diaz M, Biosens & Bioelec, 2005

60 Alternative detection technologies: Aptamers
Aptamers, in contrast to protein-based antibodies, are simply ‘chemical’ or NA antibodies CSIR- ESAT and CFP-10 aptamers, LAM, IFN-g, and Tumi aptamer array

61 Aptamers and a SERS detection platform
We have generated aptamers to TB-specific antigens (CSIR- Shooz Kathi) Grand Challenges Canada (J Blackburn) to develop a platform using antigen-specific aptamers and a SERS detection platform Surface enhanced resonance spectroscopy

62 Technological innovation is not enough- other challenges
Lack of private investment because of perceived lack of return (changing rapidly) Need better regulatory standards for approval, and these need international harmonisation Variable quality of diagnostic services, need to improve quality control More innovation in developing countries (ANDI, Gates etc) including involvement from EDCTP, Wellcome etc New ways to deal with IP and patent fees Translation from research to policy- need streamlining of approval process and guidance for high burden settings Robust health care systems with good supply chain management Better representation in medical and nursing curricula …the challenge will be

63 Summary Xpert- good test but expensive and suboptimal PPV for R resistance (no H, FQ, SLID readout) Hain MTBDRplus- main drawback was poor performance in smear negative TB (version 2.0) Hain SL- only useful in smear pos TB and does not distinguish SLIDs Revolution in the development of new and POC diagnostic platforms Major challenge is to include DR-TB readouts Need platforms that will give multiplex readouts – TB, HIV, pneumonia, other OI, malaria etc Challenge of bringing these to market and incorporating them into clinical algorithms and niche areas taking into account clinical context …the challenge will be

64

65 Funding Agencies: EUFP7 EDCTP Discovery NIH Fogerty South African
To give you a brief overview overview of my talk. I will 1st describe the epi of XDR-TB in Africa……..hardly any …………Hot of the press South African National Research Foundation South African MRC EDCTP


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