Conference Material > Poster
Solaiman AP, Venables E, Roxas MRC, Mateo M, Castro R, et al.
MSF Scientific Days Asia. 8 November 2024
Conference Material > Poster
Nacis JS, Serafico ME, Frane RD, Domalanta-Ronquillo DGA, Licayan JJSL, et al.
MSF Paediatric Days 2024. 3 May 2024; DOI:10.57740/sde6xMYtNR
Conference Material > Abstract
Thadhani TAF, Phillips EY
Epicentre Scientific Day Paris 2023. 8 June 2023
BACKGROUND
The World Health Organization recommends the use of computer-aided detection (CAD) in conjunction with chest X-rays (CXR) for tuberculosis (TB) screening and triaging in individuals aged 15 and above. This study assessed the feasibility of implementing CAD for TB active case finding (ACF) in Tondo, Manila, Philippines, including a crucial calibration process to determine the appropriate threshold for referring individuals for TB confirmatory testing.
METHODS
We conducted a prospective description of programmatic activities, TB ACF of individuals aged 15 years and above using CAD, and a mixed-methods feasibility and acceptability study in the catchment area of four health centres in Tondo. The calibration process employed an informal mixed methods approach to define, and reactively adjust, a threshold based on the Xpert MTB/Rif positivity rate, Xpert capacity, radiologists' sensitivity and user acceptability. Patients with a CAD score above the defined threshold were directed for sputum collection and Xpert testing.
RESULTS
The initial threshold, set at 25, resulted in a 35% referral rate for Xpert testing, which was subsequently increased to 28 (34% referral) to align with Xpert system capacity. 4,853 patients were included, with 13% testing positive on the symptom screening. The Xpert positivity rate was 5% among individuals screened, 13% among individuals tested, and 15% among individuals with a CAD score of 28 or higher. Users found CAD4TB® both feasible and acceptable, provided there were dedicated human resources with technical capacity for CAD implementation and the project design accounted for CAD limitations. The use of CAD increased screening capacity and supported decision-making.
CONCLUSION
The ACF conducted in Tondo revealed a remarkably high positivity rate among the screened individuals. CAD enables the rapid screening of patients in the community with reduced turnaround times. If the implementation accounts for the limitations identified, CAD can be a powerful tool for TB screening.
KEY MESSAGE
CAD4TB® implementation in Tondo, Manila, was assessed for TB screening feasibility. Promising results indicate increased capacity and support for decision-making, emphasizing potential as a powerful tool.
This abstract is not to be quoted for publication.
The World Health Organization recommends the use of computer-aided detection (CAD) in conjunction with chest X-rays (CXR) for tuberculosis (TB) screening and triaging in individuals aged 15 and above. This study assessed the feasibility of implementing CAD for TB active case finding (ACF) in Tondo, Manila, Philippines, including a crucial calibration process to determine the appropriate threshold for referring individuals for TB confirmatory testing.
METHODS
We conducted a prospective description of programmatic activities, TB ACF of individuals aged 15 years and above using CAD, and a mixed-methods feasibility and acceptability study in the catchment area of four health centres in Tondo. The calibration process employed an informal mixed methods approach to define, and reactively adjust, a threshold based on the Xpert MTB/Rif positivity rate, Xpert capacity, radiologists' sensitivity and user acceptability. Patients with a CAD score above the defined threshold were directed for sputum collection and Xpert testing.
RESULTS
The initial threshold, set at 25, resulted in a 35% referral rate for Xpert testing, which was subsequently increased to 28 (34% referral) to align with Xpert system capacity. 4,853 patients were included, with 13% testing positive on the symptom screening. The Xpert positivity rate was 5% among individuals screened, 13% among individuals tested, and 15% among individuals with a CAD score of 28 or higher. Users found CAD4TB® both feasible and acceptable, provided there were dedicated human resources with technical capacity for CAD implementation and the project design accounted for CAD limitations. The use of CAD increased screening capacity and supported decision-making.
CONCLUSION
The ACF conducted in Tondo revealed a remarkably high positivity rate among the screened individuals. CAD enables the rapid screening of patients in the community with reduced turnaround times. If the implementation accounts for the limitations identified, CAD can be a powerful tool for TB screening.
KEY MESSAGE
CAD4TB® implementation in Tondo, Manila, was assessed for TB screening feasibility. Promising results indicate increased capacity and support for decision-making, emphasizing potential as a powerful tool.
This abstract is not to be quoted for publication.
Journal Article > ResearchFull Text
Public Health Nutr. 1 June 2023; Volume 26 (Issue 6); 1210-1221.; DOI:10.1017/S1368980023000149
Briend A, Myatt M, Berkley JA, Black RE, Boyd EM, et al.
Public Health Nutr. 1 June 2023; Volume 26 (Issue 6); 1210-1221.; DOI:10.1017/S1368980023000149
OBJECTIVE
To compare the prognostic value of mid-upper arm circumference (MUAC), weight-for-height Z-score (WHZ) and weight-for-age Z-score (WAZ) for predicting death over periods of 1, 3 and 6 months follow-up in children.
DESIGN
Pooled analysis of twelve prospective studies examining survival after anthropometric assessment. Sensitivity and false-positive ratios to predict death within 1, 3 and 6 months were compared for three individual anthropometric indices and their combinations.
SETTING
Community-based, prospective studies from twelve countries in Africa and Asia.
PARTICIPANTS
Children aged 6–59 months living in the study areas.
RESULTS
For all anthropometric indices, the receiver operating characteristic curves were higher for shorter than for longer durations of follow-up. Sensitivity was higher for death with 1-month follow-up compared with 6 months by 49 % (95 % CI (30, 69)) for MUAC < 115 mm (P < 0·001), 48 % (95 % CI (9·4, 87)) for WHZ < -3 (P < 0·01) and 28 % (95 % CI (7·6, 42)) for WAZ < -3 (P < 0·005). This was accompanied by an increase in false positives of only 3 % or less. For all durations of follow-up, WAZ < -3 identified more children who died and were not identified by WHZ < -3 or by MUAC < 115 mm, 120 mm or 125 mm, but the use of WAZ < -3 led to an increased false-positive ratio up to 16·4 % (95 % CI (12·0, 20·9)) compared with 3·5 % (95 % CI (0·4, 6·5)) for MUAC < 115 mm alone.
CONCLUSIONS
Frequent anthropometric measurements significantly improve the identification of malnourished children with a high risk of death without markedly increasing false positives. Combining two indices increases sensitivity but also increases false positives among children meeting case definitions.
To compare the prognostic value of mid-upper arm circumference (MUAC), weight-for-height Z-score (WHZ) and weight-for-age Z-score (WAZ) for predicting death over periods of 1, 3 and 6 months follow-up in children.
DESIGN
Pooled analysis of twelve prospective studies examining survival after anthropometric assessment. Sensitivity and false-positive ratios to predict death within 1, 3 and 6 months were compared for three individual anthropometric indices and their combinations.
SETTING
Community-based, prospective studies from twelve countries in Africa and Asia.
PARTICIPANTS
Children aged 6–59 months living in the study areas.
RESULTS
For all anthropometric indices, the receiver operating characteristic curves were higher for shorter than for longer durations of follow-up. Sensitivity was higher for death with 1-month follow-up compared with 6 months by 49 % (95 % CI (30, 69)) for MUAC < 115 mm (P < 0·001), 48 % (95 % CI (9·4, 87)) for WHZ < -3 (P < 0·01) and 28 % (95 % CI (7·6, 42)) for WAZ < -3 (P < 0·005). This was accompanied by an increase in false positives of only 3 % or less. For all durations of follow-up, WAZ < -3 identified more children who died and were not identified by WHZ < -3 or by MUAC < 115 mm, 120 mm or 125 mm, but the use of WAZ < -3 led to an increased false-positive ratio up to 16·4 % (95 % CI (12·0, 20·9)) compared with 3·5 % (95 % CI (0·4, 6·5)) for MUAC < 115 mm alone.
CONCLUSIONS
Frequent anthropometric measurements significantly improve the identification of malnourished children with a high risk of death without markedly increasing false positives. Combining two indices increases sensitivity but also increases false positives among children meeting case definitions.
Journal Article > ResearchFull Text
Public Health Nutr. 3 February 2023; Volume 26 (Issue 4); 803-819.; DOI:10.1017/S136898002300023X
Khara T, Myatt M, Sadler K, Bahwere P, Berkley JA, et al.
Public Health Nutr. 3 February 2023; Volume 26 (Issue 4); 803-819.; DOI:10.1017/S136898002300023X
OBJECTIVE
To understand which anthropometric diagnostic criteria best discriminate higher from lower risk of death in children and explore programme implications.
DESIGN
A multiple cohort individual data meta-analysis of mortality risk (within 6 months of measurement) by anthropometric case definitions. Sensitivity, specificity, informedness and inclusivity in predicting mortality, face validity and compatibility with current standards and practice were assessed and operational consequences were modelled.
SETTING
Community-based cohort studies in twelve low-income countries between 1977 and 2013 in settings where treatment of wasting was not widespread.
PARTICIPANTS
Children aged 6 to 59 months.
RESULTS
Of the twelve anthropometric case definitions examined, four (weight-for-age Z-score (WAZ) <−2), (mid-upper arm circumference (MUAC) <125 mm), (MUAC < 115 mm or WAZ < −3) and (WAZ < −3) had the highest informedness in predicting mortality. A combined case definition (MUAC < 115 mm or WAZ < −3) was better at predicting deaths associated with weight-for-height Z-score <−3 and concurrent wasting and stunting (WaSt) than the single WAZ < −3 case definition. After the assessment of all criteria, the combined case definition performed best. The simulated workload for programmes admitting based on MUAC < 115 mm or WAZ < −3, when adjusted with a proxy for required intensity and/or duration of treatment, was 1·87 times larger than programmes admitting on MUAC < 115 mm alone.
CONCLUSIONS
A combined case definition detects nearly all deaths associated with severe anthropometric deficits suggesting that therapeutic feeding programmes may achieve higher impact (prevent mortality and improve coverage) by using it. There remain operational questions to examine further before wide-scale adoption can be recommended.
To understand which anthropometric diagnostic criteria best discriminate higher from lower risk of death in children and explore programme implications.
DESIGN
A multiple cohort individual data meta-analysis of mortality risk (within 6 months of measurement) by anthropometric case definitions. Sensitivity, specificity, informedness and inclusivity in predicting mortality, face validity and compatibility with current standards and practice were assessed and operational consequences were modelled.
SETTING
Community-based cohort studies in twelve low-income countries between 1977 and 2013 in settings where treatment of wasting was not widespread.
PARTICIPANTS
Children aged 6 to 59 months.
RESULTS
Of the twelve anthropometric case definitions examined, four (weight-for-age Z-score (WAZ) <−2), (mid-upper arm circumference (MUAC) <125 mm), (MUAC < 115 mm or WAZ < −3) and (WAZ < −3) had the highest informedness in predicting mortality. A combined case definition (MUAC < 115 mm or WAZ < −3) was better at predicting deaths associated with weight-for-height Z-score <−3 and concurrent wasting and stunting (WaSt) than the single WAZ < −3 case definition. After the assessment of all criteria, the combined case definition performed best. The simulated workload for programmes admitting based on MUAC < 115 mm or WAZ < −3, when adjusted with a proxy for required intensity and/or duration of treatment, was 1·87 times larger than programmes admitting on MUAC < 115 mm alone.
CONCLUSIONS
A combined case definition detects nearly all deaths associated with severe anthropometric deficits suggesting that therapeutic feeding programmes may achieve higher impact (prevent mortality and improve coverage) by using it. There remain operational questions to examine further before wide-scale adoption can be recommended.
Journal Article > ResearchFull Text
PLOS Glob Public Health. 7 December 2022; Volume 2 (Issue 12); e0001337.; DOI:10.1371/journal.pgph.0001337
Sweeney S, Berry C, Kazounis E, Motta I, Vassall A, et al.
PLOS Glob Public Health. 7 December 2022; Volume 2 (Issue 12); e0001337.; DOI:10.1371/journal.pgph.0001337
Current options for treating tuberculosis (TB) that is resistant to rifampicin (RR-TB) are few, and regimens are often long and poorly tolerated. Following recent evidence from the TB-PRACTECAL trial countries are considering programmatic uptake of 6-month, all-oral treatment regimens. We used a Markov model to estimate the incremental cost-effectiveness of three regimens containing bedaquiline, pretomanid and linezolid (BPaL) with and without moxifloxacin (BPaLM) or clofazimine (BPaLC) compared with the current mix of long and short standard of care (SOC) regimens to treat RR-TB from the provider perspective in India, Georgia, Philippines, and South Africa. We estimated total costs (2019 USD) and disability-adjusted life years (DALYs) over a 20-year time horizon. Costs and DALYs were discounted at 3% in the base case. Parameter uncertainty was tested with univariate and probabilistic sensitivity analysis. We found that all three regimens would improve health outcomes and reduce costs compared with the current programmatic mix of long and short SOC regimens in all four countries. BPaL was the most cost-saving regimen in all countries, saving $112-$1,173 per person. BPaLM was the preferred regimen at a willingness to pay per DALY of 0.5 GDP per capita in all settings. Our findings indicate BPaL-based regimens are likely to be cost-saving and more effective than the current standard of care in a range of settings. Countries should consider programmatic uptake of BPaL-based regimens.
Journal Article > Pre-Print
medRxiv. 10 November 2022; DOI:10.1101/2022.11.08.22282060
Sweeney S, Berry C, Kazounis E, Motta I, Vassall A, et al.
medRxiv. 10 November 2022; DOI:10.1101/2022.11.08.22282060
INTRODUCTION
Current options for treating tuberculosis (TB) that is resistant to rifampicin (RR-TB) are few, and regimens are often long and poorly tolerated. Following recent evidence from the TB-PRACTECAL trial countries are considering programmatic uptake of 6-month, all-oral treatment regimens.
METHODS
We used a Markov model to estimate the incremental cost-effectiveness of three regimens containing bedaquiline, pretomanid and linezolid (BPaL) with and without moxifloxacin (BPaLM) or clofazimine (BPaLC) compared with the current mix of long and short standard of care (SOC) regimens to treat RR-TB from the provider perspective in India, Georgia, Philippines, and South Africa. We estimated total costs (2019 USD) and disability-adjusted life years (DALYs) over a 20-year time horizon. Costs and DALYs were discounted at 3% in the base case. Parameter uncertainty was tested with univariate and probabilistic sensitivity analysis.
RESULTS
We found that all three regimens would improve health outcomes and reduce costs compared with the current programmatic mix of long and short SOC regimens in all four countries. BPaL was the most cost-saving regimen in all countries, saving $112-$1,173 per person. BPaLM was the preferred regimen at a willingness to pay per DALY of 0.5 GDP per capita in all settings.
CONCLUSIONS
Our findings indicate BPaL-based regimens are likely to be cost-saving and more effective than the current standard of care in a range of settings. Countries should consider programmatic uptake of BPaL-based regimens.
Current options for treating tuberculosis (TB) that is resistant to rifampicin (RR-TB) are few, and regimens are often long and poorly tolerated. Following recent evidence from the TB-PRACTECAL trial countries are considering programmatic uptake of 6-month, all-oral treatment regimens.
METHODS
We used a Markov model to estimate the incremental cost-effectiveness of three regimens containing bedaquiline, pretomanid and linezolid (BPaL) with and without moxifloxacin (BPaLM) or clofazimine (BPaLC) compared with the current mix of long and short standard of care (SOC) regimens to treat RR-TB from the provider perspective in India, Georgia, Philippines, and South Africa. We estimated total costs (2019 USD) and disability-adjusted life years (DALYs) over a 20-year time horizon. Costs and DALYs were discounted at 3% in the base case. Parameter uncertainty was tested with univariate and probabilistic sensitivity analysis.
RESULTS
We found that all three regimens would improve health outcomes and reduce costs compared with the current programmatic mix of long and short SOC regimens in all four countries. BPaL was the most cost-saving regimen in all countries, saving $112-$1,173 per person. BPaLM was the preferred regimen at a willingness to pay per DALY of 0.5 GDP per capita in all settings.
CONCLUSIONS
Our findings indicate BPaL-based regimens are likely to be cost-saving and more effective than the current standard of care in a range of settings. Countries should consider programmatic uptake of BPaL-based regimens.
Journal Article > ResearchFull Text
Disaster Med Public Health Prep. 15 December 2016; Volume 11 (Issue 3); 285-289.; DOI:10.1017/dmp.2016.135
Ali E, Ferir MC, Reid AJ, Gray H, van den Boogaard W, et al.
Disaster Med Public Health Prep. 15 December 2016; Volume 11 (Issue 3); 285-289.; DOI:10.1017/dmp.2016.135
OBJECTIVES
Typhoon Haiyan hit the Philippines in November 2013 and left a trail of destruction. As part of its emergency response, Médecins Sans Frontières distributed materials for reconstructing houses and boats as standardized kits to be shared between households. Community engagement was sought and communities were empowered in deciding how to make the distributions. We aimed to answer, Was this effective and what lessons were learned?
METHODS
A cross-sectional survey using a semi-structured questionnaire was conducted in May 2014 and included all community leaders and 269 households in 22 barangays (community administrative areas).
RESULTS
All houses were affected by the typhoon, of which 182 (68%) were totally damaged. All households reported having received and used the housing material. However, in 238 (88%) house repair was incomplete because the materials provided were insufficient or inappropriate for the required repairs.
CONCLUSION
This experience of emergency mass distribution of reconstruction or repair materials of houses and boats led by the local community was encouraging. The use of "standardized kits" resulted in equity issues, because households were subjected to variable degrees of damage. A possible way out is to follow up the emergency distribution with a needs assessment and a tailored distribution. (Disaster Med Public Health Preparedness. 2017;11:285-289).
Typhoon Haiyan hit the Philippines in November 2013 and left a trail of destruction. As part of its emergency response, Médecins Sans Frontières distributed materials for reconstructing houses and boats as standardized kits to be shared between households. Community engagement was sought and communities were empowered in deciding how to make the distributions. We aimed to answer, Was this effective and what lessons were learned?
METHODS
A cross-sectional survey using a semi-structured questionnaire was conducted in May 2014 and included all community leaders and 269 households in 22 barangays (community administrative areas).
RESULTS
All houses were affected by the typhoon, of which 182 (68%) were totally damaged. All households reported having received and used the housing material. However, in 238 (88%) house repair was incomplete because the materials provided were insufficient or inappropriate for the required repairs.
CONCLUSION
This experience of emergency mass distribution of reconstruction or repair materials of houses and boats led by the local community was encouraging. The use of "standardized kits" resulted in equity issues, because households were subjected to variable degrees of damage. A possible way out is to follow up the emergency distribution with a needs assessment and a tailored distribution. (Disaster Med Public Health Preparedness. 2017;11:285-289).
Journal Article > CommentarySubscription Only
Med J Aust. 1 May 2014; Volume 200 (Issue 9); 512-512.; DOI:10.5694/mja14.00143
Martinez Garcia D, Brown AL
Med J Aust. 1 May 2014; Volume 200 (Issue 9); 512-512.; DOI:10.5694/mja14.00143
Journal Article > ResearchFull Text
Lancet. 19 April 2011; Volume 377 (Issue 9776); DOI:10.1016/S0140-6736(11)60438-8
Boehme CC, Nicol MP, Nabeta P, Michael JS, Gotuzzo E, et al.
Lancet. 19 April 2011; Volume 377 (Issue 9776); DOI:10.1016/S0140-6736(11)60438-8
BACKGROUND: The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA, USA) can detect tuberculosis and its multidrug-resistant form with very high sensitivity and specificity in controlled studies, but no performance data exist from district and subdistrict health facilities in tuberculosis-endemic countries. We aimed to assess operational feasibility, accuracy, and effectiveness of implementation in such settings. METHODS: We assessed adults (≥18 years) with suspected tuberculosis or multidrug-resistant tuberculosis consecutively presenting with cough lasting at least 2 weeks to urban health centres in South Africa, Peru, and India, drug-resistance screening facilities in Azerbaijan and the Philippines, and an emergency room in Uganda. Patients were excluded from the main analyses if their second sputum sample was collected more than 1 week after the first sample, or if no valid reference standard or MTB/RIF test was available. We compared one-off direct MTB/RIF testing in nine microscopy laboratories adjacent to study sites with 2-3 sputum smears and 1-3 cultures, dependent on site, and drug-susceptibility testing. We assessed indicators of robustness including indeterminate rate and between-site performance, and compared time to detection, reporting, and treatment, and patient dropouts for the techniques used. FINDINGS: We enrolled 6648 participants between Aug 11, 2009, and June 26, 2010. One-off MTB/RIF testing detected 933 (90·3%) of 1033 culture-confirmed cases of tuberculosis, compared with 699 (67·1%) of 1041 for microscopy. MTB/RIF test sensitivity was 76·9% in smear-negative, culture-positive patients (296 of 385 samples), and 99·0% specific (2846 of 2876 non-tuberculosis samples). MTB/RIF test sensitivity for rifampicin resistance was 94·4% (236 of 250) and specificity was 98·3% (796 of 810). Unlike microscopy, MTB/RIF test sensitivity was not significantly lower in patients with HIV co-infection. Median time to detection of tuberculosis for the MTB/RIF test was 0 days (IQR 0-1), compared with 1 day (0-1) for microscopy, 30 days (23-43) for solid culture, and 16 days (13-21) for liquid culture. Median time to detection of resistance was 20 days (10-26) for line-probe assay and 106 days (30-124) for conventional drug-susceptibility testing. Use of the MTB/RIF test reduced median time to treatment for smear-negative tuberculosis from 56 days (39-81) to 5 days (2-8). The indeterminate rate of MTB/RIF testing was 2·4% (126 of 5321 samples) compared with 4·6% (441 of 9690) for cultures. INTERPRETATION: The MTB/RIF test can effectively be used in low-resource settings to simplify patients' access to early and accurate diagnosis, thereby potentially decreasing morbidity associated with diagnostic delay, dropout and mistreatment. FUNDING: Foundation for Innovative New Diagnostics, Bill & Melinda Gates Foundation, European and Developing Countries Clinical Trials Partnership (TA2007.40200.009), Wellcome Trust (085251/B/08/Z), and UK Department for International Development.