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Ombelet S, Natale A, Ronat JB, Kesteman T, Vandenberg O, Jacobs J, Hardy L. Biphasic versus monophasic manual blood culture bottles for low-resource settings: an in-vitro study. THE LANCET MICROBE 2022; 3:e124-e132. [DOI: 10.1016/s2666-5247(21)00241-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 08/19/2021] [Accepted: 08/25/2021] [Indexed: 11/29/2022] Open
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Surface-enhanced Raman spectroscopy for comparison of serum samples of typhoid and tuberculosis patients of different stages. Photodiagnosis Photodyn Ther 2021; 35:102426. [PMID: 34217869 DOI: 10.1016/j.pdpdt.2021.102426] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/25/2021] [Accepted: 06/28/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Surface-enhanced Raman spectroscopy (SERS) is a reliable tool for the identification and differentiation of two different human pathological conditions sharing the same symptomology, typhoid and tuberculosis (TB). OBJECTIVES To explore the potential of surface-enhanced Raman spectroscopy for differentiation of two different diseases showing the same symptoms and analysis by principal component analysis (PCA) and partial least square discriminate analysis (PLS-DA). METHODS Serum samples of clinically diagnosed typhoid and tuberculosis infected individuals were analyzed and differentiated by SERS using silver nanoparticles (Ag NPs) as a SERS substrate. For this purpose, the collected serum samples were analyzed under the SERS instrument and unique SERS spectra of typhoid and tuberculosis were compared showing notable spectral differences in protein, lipid and carbohydrates features. Different stages of the diseased class of typhoid (Early acute and late acute stage) and tuberculosis (Pulmonary and extra-pulmonary stage) were compared with each other and with healthy human serum samples, which were significantly separated. Moreover, SERS data was analyzed using multivariate data analysis techniques including principal component analysis (PCA) and partial least square discriminate analysis (PLS-DA) and differences were so prominent to observe. RESULTS SERS Spectral data of typhoid and tuberculosis showed clear differences and were significantly separated using PCA. SERS spectral data of both stages of typhoid and tuberculosis were separated according to 1st principle component. Moreover, by analyzing data using partial least square discriminate analysis, differentiation of two disease classes were considered more valid with a 100% value of sensitivity, specificity and accuracy. CONCLUSION SERS can be employed for identification and comparison of two different human pathological conditions sharing same symptomology.
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Tahira M, Nawaz H, Majeed MI, Rashid N, Tabbasum S, Abubakar M, Ahmad S, Akbar S, Bashir S, Kashif M, Ali S, Hyat H. Surface-enhanced Raman spectroscopy analysis of serum samples of typhoid patients of different stages. Photodiagnosis Photodyn Ther 2021; 34:102329. [PMID: 33965602 DOI: 10.1016/j.pdpdt.2021.102329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/14/2021] [Accepted: 04/30/2021] [Indexed: 01/04/2023]
Abstract
BACKGROUND Surface-enhanced Raman spectroscopy (SERS) of body fluids is considered a quick, simple and easy to use method for the diagnosis of disease. OBJECTIVES To evaluate rapid, reliable, and non-destructive SERS-based diagnostic tool with multivariate data analysis including principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) for classification of different stages of typhoid on the basis of characteristic SERS spectral features. METHODS SERS has been used for analysis of serum samples of different stages of typhoid including early acute stage and late acute stage in comparison with healthy samples, in order to investigate capability of this technique for diagnosis of typhoid. SERS spectral features associated with the biochemical changes taking place during the development of the typhoid fever were analyzed and identified. RESULTS The value of area under the receiver operating characteristics (AUROC) for early acute stage versus healthy is 0.87 and that for healthy versus late acute stage is 0.52. PLS-DA classifier model gives values of 100 % for accuracy, sensitivity and specificity, respectively for the SERS spectral data sets of healthy versus early acute stage. Moreover, this classifier model gives values of 91 %, 89 % and 97 % for accuracy, sensitivity and specificity, respectively for the SERS spectral data sets of healthy versus late acute stage. CONCLUSIONS Based on preliminary work it is concluded that SERS has potential to diagnose various stages of typhoid fever including early acute and late acute stage in comparison with healthy samples.
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Affiliation(s)
- Maimoona Tahira
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Haq Nawaz
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan.
| | - Muhammad Irfan Majeed
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan.
| | - Nosheen Rashid
- Department of Chemistry, University of Central Punjab, Faisalabad Campus, Faisalabad, Pakistan
| | - Shaheera Tabbasum
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Muhammad Abubakar
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Shamsheer Ahmad
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Saba Akbar
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Saba Bashir
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Muhammad Kashif
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Saqib Ali
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
| | - Hamza Hyat
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, 38040, Pakistan
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Iskandar K, Molinier L, Hallit S, Sartelli M, Hardcastle TC, Haque M, Lugova H, Dhingra S, Sharma P, Islam S, Mohammed I, Naina Mohamed I, Hanna PA, Hajj SE, Jamaluddin NAH, Salameh P, Roques C. Surveillance of antimicrobial resistance in low- and middle-income countries: a scattered picture. Antimicrob Resist Infect Control 2021; 10:63. [PMID: 33789754 PMCID: PMC8011122 DOI: 10.1186/s13756-021-00931-w] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 03/22/2021] [Indexed: 01/07/2023] Open
Abstract
Data on comprehensive population-based surveillance of antimicrobial resistance is lacking. In low- and middle-income countries, the challenges are high due to weak laboratory capacity, poor health systems governance, lack of health information systems, and limited resources. Developing countries struggle with political and social dilemma, and bear a high health and economic burden of communicable diseases. Available data are fragmented and lack representativeness which limits their use to advice health policy makers and orientate the efficient allocation of funding and financial resources on programs to mitigate resistance. Low-quality data means soaring rates of antimicrobial resistance and the inability to track and map the spread of resistance, detect early outbreaks, and set national health policy to tackle resistance. Here, we review the barriers and limitations of conducting effective antimicrobial resistance surveillance, and we highlight multiple incremental approaches that may offer opportunities to strengthen population-based surveillance if tailored to the context of each country.
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Affiliation(s)
- Katia Iskandar
- Department of Mathématiques Informatique et Télécommunications, Université Toulouse III, Paul Sabatier, INSERM, UMR 1027, 31000, Toulouse, France.
- INSPECT-LB, Institut National de Santé Publique, d'Épidémiologie Clinique et de Toxicologie-Liban, Beirut, 6573-14, Lebanon.
- Faculty of Pharmacy, Lebanese University, Mount Lebanon, Lebanon.
| | - Laurent Molinier
- Faculté de Médecine, Equipe constitutive du CERPOP, UMR1295, unité mixte INSERM, Université Paul Sabatier Toulouse III, 31000, Toulouse, France
| | - Souheil Hallit
- INSPECT-LB, Institut National de Santé Publique, d'Épidémiologie Clinique et de Toxicologie-Liban, Beirut, 6573-14, Lebanon
- Faculty of Medicine and Medical Sciences, Holy Spirit University of Kaslik (USEK), Jounieh, Lebanon
| | - Massimo Sartelli
- Department of Surgery, University of Macerata, 62100, Macerata, Italy
| | - Timothy Craig Hardcastle
- Department of Trauma Service, Inkosi Albert Luthuli Central Hospital, Durban, 4091, South Africa
- Department of Surgery, Nelson Mandela School of Clinical Medicine, University of KwaZulu-Natal, Congela, 4041, Durban, South Africa
| | - Mainul Haque
- Unit of Pharmacology, Faculty of Medicine and Defence Health, Universiti Pertahanan Nasional Malaysia (National Defence University of Malaysia), Kem Perdana Sungai Besi, 57000, Malaysia
| | - Halyna Lugova
- Faculty of Medicine and Defence Health, National Defence University of Malaysia, 57000, Kuala Lumpur, Malaysia
| | - Sameer Dhingra
- Department of Pharmacy Practice, National Institute of Pharmaceutical Education and Research (NIPER) Hajipur, Bihar, India
| | - Paras Sharma
- Department of Pharmacognosy, BVM College of Pharmacy, Gwalior, India
| | - Salequl Islam
- Department of Microbiology, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| | - Irfan Mohammed
- Department of Restorative Dentistry, Federal University of Pelotas School of Dentistry, Pelotas, RS, 96020-010, Brazil
| | - Isa Naina Mohamed
- Pharmacoepidemiology and Drug Safety Unit, Pharmacology Department, Medical Faculty, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Kuala Lumpur, Malaysia
| | - Pierre Abi Hanna
- Faculty of Pharmacy, Lebanese University, Mount Lebanon, Lebanon
| | - Said El Hajj
- Department of Medicine, Lebanese University, Beirut, Lebanon
| | - Nurul Adilla Hayat Jamaluddin
- Pharmacoepidemiology and Drug Safety Unit, Pharmacology Department, Medical Faculty, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Kuala Lumpur, Malaysia
| | - Pascale Salameh
- INSPECT-LB, Institut National de Santé Publique, d'Épidémiologie Clinique et de Toxicologie-Liban, Beirut, 6573-14, Lebanon
- Department of Medicine, Lebanese University, Beirut, Lebanon
- Faculty of Medicine, University of Nicosia, Nicosia, Cyprus
| | - Christine Roques
- Department of Bactériologie-Hygiène, Centre Hospitalier Universitaire, Hôpital Purpan, 31330, Toulouse, France
- Department of Bioprocédés et Systèmes Microbiens, Laboratoire de Génie Chimique, Université Paul Sabatier Toulouse III, UMR 5503, 31330, Toulouse, France
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Wight J, Varin MP, Robertson GJ, Huot Y, Lang AS. Microbiology in the Field: Construction and Validation of a Portable Incubator for Real-Time Quantification of Coliforms and Other Bacteria. Front Public Health 2020; 8:607997. [PMID: 33324604 PMCID: PMC7723852 DOI: 10.3389/fpubh.2020.607997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 10/28/2020] [Indexed: 11/24/2022] Open
Abstract
Performing microbiological assays on environmental samples in field settings poses logistical challenges with respect to the availability of suitable equipment or the ability to get samples to the laboratory in a timely fashion. For example, the viability of some bacteria can decrease greatly between sampling and arrival to the laboratory for processing. We developed and constructed rugged, reliable, and cost-effective portable incubators that were used by 10 independent field teams to perform microbiological assays on surface water samples from lakes across Canada. Rigorous testing and validation of our incubators ensured that incubation conditions were consistent within and across all 10 field teams and 2 sampling years. Samples from all sites were processed in duplicate and bacterial counts were highly repeatable within and across sampling teams. Bacterial counts were also found to be statistically equivalent to counts obtained with standard laboratory techniques using a conventional incubator. Using this method, thermotolerant coliforms (TTCs) and Escherichia coli were quantified from 432 lakes, allowing comparison to both historical datasets that relied on TTCs and those following current guidelines that use E. coli counts. We found higher loads at the shoreline than the middle of lakes and different patterns between ecozones. E. coli was not frequently detected, but many lakes exceeded Canadian guideline values for activities such as swimming and some even exceeded the guideline value for secondary recreational activities such as boating. To the best of our knowledge, this is the largest bacteriological water quality assessment of freshwater lakes to date in terms of both spatial scale and the number of lakes sampled. Our incubator design can be easily adapted for a wide variety of researcher goals and represents a robust platform for field studies and other applications, including those in remote or low-resources settings.
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Affiliation(s)
- Jordan Wight
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Marie-Pierre Varin
- Département de Géomatique Appliquée, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Gregory J Robertson
- Wildlife Research Division, Environment and Climate Change Canada, Mount Pearl, NL, Canada
| | - Yannick Huot
- Département de Géomatique Appliquée, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Andrew S Lang
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, Canada
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Ombelet S, Peeters M, Phe C, Tsoumanis A, Kham C, Teav S, Vlieghe E, Phe T, Jacobs J. Nonautomated Blood Cultures in a Low-Resource Setting: Optimizing the Timing of Blind Subculture. Am J Trop Med Hyg 2020; 104:612-621. [PMID: 33258440 PMCID: PMC7866355 DOI: 10.4269/ajtmh.20-0249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/27/2020] [Indexed: 12/29/2022] Open
Abstract
Laboratory procedures for blood cultures in a hospital in Phnom Penh were adapted to optimize detection of Burkholderia pseudomallei, an important pathogen in this setting. The effects of these changes are analyzed in this study. Blood cultures consisted of two BacT/ALERT bottles (bioMérieux, Marcy-l’Etoile, France). Growth was detected visually by daily inspection of the bottles. In 2016, the aerobic–anaerobic pair (FA/FN FAN) was substituted by an aerobic pair of BacT/ALERT FA Plus bottles. Blind subculture (BS) (subculture in the absence of visual growth) was advanced from day 3 to day 2 of incubation in July 2016. In July 2018, it was further advanced to day 1 of incubation. From July 2016 to October 2019, 9,760 blood cultures were sampled. The proportion of cultures showing pathogen growth decreased from 9.6% to 6.8% after the implementation of the laboratory changes (P < 0.001). Advancing the BS from day 3 to day 2 led to an increased proportion of pathogens detected by day 3 (92.8% versus 82.3%; P < 0.001); for B. pseudomallei, this increase was even more remarkable (92.0% versus 18.2%). Blind subculture on day 1 similarly increased the proportion of pathogens detected by day 2 (82.9% versus 69.0% overall, 66.7% versus 10.0% for B. pseudomallei; both P < 0.001). However, after implementation of day 1 subculture, a decrease in recovery of B. pseudomallei was observed (12.4% of all pathogens versus 4.3%; P < 0.001). In conclusion, earlier subculture significantly shortens time to detection and time to actionable results. Some organisms may be missed by performing an early subculture, especially those that grow more slowly.
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Affiliation(s)
- Sien Ombelet
- Department of Immunology, Microbiology and Transplantation, KULeuven, Leuven, Belgium.,Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Marjan Peeters
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Chhundy Phe
- Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia
| | - Achilleas Tsoumanis
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Chun Kham
- Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia
| | - Syna Teav
- Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia
| | - Erika Vlieghe
- Department of General Internal Medicine, Infectious and Tropical Diseases, University Hospital Antwerp, Antwerp, Belgium
| | - Thong Phe
- Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia
| | - Jan Jacobs
- Department of Immunology, Microbiology and Transplantation, KULeuven, Leuven, Belgium.,Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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Peeters M, Ombelet S, Chung P, Tsoumanis A, Lim K, Long L, De Smet B, Kham C, Teav S, Vlieghe E, Phe T, Jacobs J. Slow growth of Burkholderia pseudomallei compared to other pathogens in an adapted blood culture system in Phnom Penh, Cambodia. J Med Microbiol 2019; 68:1159-1166. [PMID: 31188093 DOI: 10.1099/jmm.0.001011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
PURPOSE Burkholderia pseudomallei is a key pathogen causing bloodstream infections at Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia. Here, visual instead of automated detection of growth of commercial blood culture bottles is done. The present study assessed the performance of this system. METHODOLOGY Blood culture sets, consisting of paired adult aerobic and anaerobic bottles (bioMérieux, FA FAN 259791 and FN FAN 252793) were incubated in a standard incubator for 7 days after reception. Each day, the bottle growth indicator was visually inspected for colour change indicating growth. Blind subculture was performed from the aerobic bottle at day 3. RESULTS From 2010 to 2015, 11 671 sets representing 10 389 suspected bloodstream infection episodes were documented. In 1058 (10.2 %) episodes, pathogens grew; they comprised Escherichia coli (31.7 %), Salmonella Paratyphi A (13.9 %), B. pseudomallei (8.5 %), Staphylococcus aureus (7.8 %) and Klebsiella pneumoniae (7.0 %). Blind subculture yielded 72 (4.1 %) pathogens, mostly (55/72, 76.4 %) B. pseudomallei. Cumulative proportions of growth at day 2 were as follows: E. coli: 85.0 %, Salmonella Paratyphi A: 85.0 %, K. pneumoniae: 76.3 % and S. aureus: 52.2 %; for B. pseudomallei, this was only 4.0 %, which increased to 70.1 % (70/99) at day 4 mainly by detection on blind subculture (55/99). Compared to the anaerobic bottles, aerobic bottles had a higher yield and a shorter time-to-detection, particularly for B. pseudomallei. CONCLUSIONS Visual inspection for growth of commercial blood culture bottles in a low-resource setting provided satisfactory yield and time-to-detection. However, B. pseudomallei grew slowly and was mainly detected by blind subculture. The aerobic bottle outperformed the anaerobic bottle.
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Affiliation(s)
- Marjan Peeters
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Sien Ombelet
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Panha Chung
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Achilleas Tsoumanis
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Kruy Lim
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Leng Long
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Birgit De Smet
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Chun Kham
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Syna Teav
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Erika Vlieghe
- Unit of Internal Medicine and Infectious Diseases, University Hospital Antwerp, Antwerp, Belgium
| | - Thong Phe
- Sihanouk Hospital Centre of HOPE, Phnom Penh, Cambodia
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
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Koirala KD, Chappuis F, Verdonck K, Rijal S, Boelaert M. Persistent febrile illnesses in Nepal: A systematic review. Indian J Med Res 2019; 148:385-395. [PMID: 30666001 PMCID: PMC6362719 DOI: 10.4103/ijmr.ijmr_505_18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Background & objectives Although febrile illnesses are a frequent cause of consultation and hospitalization in low- and middle-income countries (LMICs), research has mainly focused on acute febrile illnesses (AFIs). In contrast, there are limited data on the causes of persistent febrile illnesses (PFIs) in LMIC. Lack of clarity on the differential diagnosis of PFIs in the rural tropics leads to the absence of diagnostic guidance tools. Methods In this study, a review of the potential causes of persistent fever defined as fever of more than seven days was done in Nepal, with a focus on nine pathogen-specific conditions. The current knowledge on their burden, distribution and diagnosis was summarized. Results Limited data were found on the incidence and public health burden of leptospirosis, murine typhus and brucellosis due to the absence of diagnostic tools outside reference laboratories and the overlap of signs and symptoms with other febrile conditions. The incidence of malaria and visceral leishmaniasis (VL) was found to be decreasing in Nepal, with some changes of the geographical areas at risk. Interpretation & conclusions This review indicates a need for more research on the causes of PFIs in Nepal and in the region and for the development of clinical guidance tailored to current local epidemiology. Guidance tools should include specific clinical features (e.g. eschar), results of rapid diagnostic tests (e.g. malaria, VL), appropriate indications for more sophisticated tests (e.g. abdominal ultrasound, polymerase chain reaction) and recommendations for adequate use of empirical treatment.
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Affiliation(s)
- Kanika Deshpande Koirala
- Department of Medicine, B.P. Koirala Institute of Health Science, Dharan, Nepal; Epidemiology and Control of Neglected Tropical Diseases Unit, Institute of Tropical Medicine, Antwerp, Belgium; Institute of Global Health, University of Geneva, Geneva, Switzerland
| | - François Chappuis
- Institute of Global Health, University of Geneva; Division of Tropical & Humanitarian Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Kristien Verdonck
- Epidemiology and Control of Neglected Tropical Diseases Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Suman Rijal
- Department of Medicine, B.P. Koirala Institute of Health Science, Dharan, Nepal
| | - Marleen Boelaert
- Epidemiology and Control of Neglected Tropical Diseases Unit, Institute of Tropical Medicine, Antwerp, Belgium
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Arora P, Thorlund K, Brenner DR, Andrews JR. Comparative accuracy of typhoid diagnostic tools: A Bayesian latent-class network analysis. PLoS Negl Trop Dis 2019; 13:e0007303. [PMID: 31067228 PMCID: PMC6527309 DOI: 10.1371/journal.pntd.0007303] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 05/20/2019] [Accepted: 03/13/2019] [Indexed: 11/19/2022] Open
Abstract
Background Typhoid fevers are infections caused by the bacteria Salmonella enterica serovar Typhi (Salmonella Typhi) and Paratyphi A, B and C (Salmonella Paratyphi). Approximately 17.8 million incident cases of typhoid fever occur annually, and incidence is highest in children. The accuracy of current diagnostic tests of typhoid fever is poorly understood. We aimed to determine the comparative accuracy of available tests for the pediatric population. Methods We first conducted a systematic literature review to identify studies that compared diagnostic tests for typhoid fever in children (aged ≤15 years) to blood culture results. We applied a Bayesian latent-class extension to a network meta-analysis model. We modelled known diagnostic properties of bone marrow culture and the relationship between bone marrow and blood culture as informative priors in a Bayesian framework. We tested sensitivities for the proportion of negative blood samples that were false as well as bone marrow sensitivity and specificity. Results We found 510 comparisons from 196 studies and 57 specific to the pediatric population. IgM-based tests outperformed their IgG-based counterparts for ELISA and Typhidot tests. The lateral flow IgG test performed comparatively well with 92% sensitivity (72% to 98% across scenario analyses) and 94% specificity. The most sensitive test of those investigated for the South Asian pediatric population was the Reverse Passive Hemagglutination Assay with 99% sensitivity (98% - 100% across scenario analyses). Adding a Widal slide test to other typhoid diagnostics did not substantially improve diagnostic performance beyond the single test alone, however, a lateral flow-based IgG rapid test combined with the typhoid/paratyphoid (TPT) assay yielded improvements in sensitivity without substantial declines in specificity and was the best performing combination test in this setting. Conclusion In the pediatric population, lateral-flow IgG, TPT and Reverse Passive Hemagglutination tests had high diagnostic accuracy compared to other diagnostics. Combinations of tests may provide a feasible option to increase diagnostic sensitivity. South Asia has the most informed set of data on typhoid diagnostic testing accuracy, and the evidence base in other important regions needs to be expanded. Typhoid fever is an infection caused by the bacterium Salmonella Typhi. Typhoid fever is rare in developed countries but remains high in the developing world. Effective treatment is available but accurate diagnosis of typhoid fever is challenging as typhoid fever can be difficult to distinguish from other infections. Bone marrow culture is the most accurate diagnostic test for typhoid fever however is invasive and not feasible in many settings. New vaccines for typhoid and the need for improved estimates of burden increases the demand for improved understanding of diagnostic accuracy. Comparing the diagnostic accuracy of tests for typhoid fever is challenging as head-to-head studies are few. We applied newly developed methods for comparative evaluation of diagnostic tests for typhoid fever in children using statistical approaches that allowed for the proper incorporation of uncertainty and comparison of tests that had not been compared directly. The lateral-flow IgG, TPT and Reverse Passive Hemagglutination tests all had good diagnostic accuracy compared to other diagnostics. Combinations of tests may provide a feasible option to increase diagnostic sensitivity. Finally, while South Asia has the most informed set of data on typhoid diagnostic testing accuracy, the evidence base in other important regions needs to be expanded.
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Affiliation(s)
- Paul Arora
- Dalla Lana School of Public Health, Division of Epidemiology, University of Toronto, Ontario, Canada
- * E-mail:
| | - Kristian Thorlund
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada
| | - Darren R. Brenner
- Departments of Oncology and Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, United States of America
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Semret M, Ndao M, Jacobs J, Yansouni CP. Point-of-care and point-of-'can': leveraging reference-laboratory capacity for integrated diagnosis of fever syndromes in the tropics. Clin Microbiol Infect 2018; 24:836-844. [PMID: 29649602 DOI: 10.1016/j.cmi.2018.03.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 01/07/2023]
Abstract
BACKGROUND There is an urgent need for integrated diagnosis of febrile syndromes able to account for multiple pathogens and to inform decisions for clinical care and public health. AIMS To reflect on the evolving roles of laboratory-based testing for non-malarial febrile illnesses (NMFIs) in low-resource settings, and to consider how advances in diagnostics, in connectivity and transport, and in implementation of quality systems may substantially enhance the capacity of reference laboratories to bridge the current gap between remote passive surveillance and clinically meaningful integrated fever diagnosis. SOURCES Iterative search of PubMed databases, organizational reports, and expert consultation. CONTENT Implementation of new technologies-such as very broad molecular panels for surveillance and mass spectrometry-may considerably diminish capability gaps in reference laboratories in low-resource settings. Although the need for clinical bacteriology diagnostics is now recognized, the lack of new simple and rapid phenotypic tests for antimicrobial resistance remains a key deficiency. Several initiatives to strengthen diagnostic preparedness for infectious disease outbreaks have highlighted the need for functional tiered laboratory networks. Recently, dramatic headway in connectivity-such as combining automated readers with the image processing and data transmission capabilities of smartphones-now allows for more complex testing and interfacing with distant laboratory information systems while reducing workload and errors. Together with connectivity to transmit and receive results, new approaches to specimen collection and transport-such as the validation of rectal swabs and the use of aerial drones to transport specimens to distant laboratories-now make remote testing feasible. The above innovations also open up the possibility of implementing quality systems through community-level diagnostic stewardship. Finally, strengthened laboratory networks actively support the feasibility of implementing quality-assured point-of-care testing where it is needed. IMPLICATIONS Recent advances offer the present-day possibility of innovations to re-invent the relationship between distant reference laboratories and end-users for integrated diagnosis of NMFIs.
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Affiliation(s)
- M Semret
- J.D. MacLean Centre for Tropical Diseases, McGill University Health Centre, Montreal, Canada
| | - M Ndao
- National Reference Centre for Parasitology, Montreal, Canada
| | - J Jacobs
- Institute of Tropical Medicine, Antwerp, Belgium; KU Leuven, Department of Microbiology and Immunology, Leuven, Belgium
| | - C P Yansouni
- J.D. MacLean Centre for Tropical Diseases, McGill University Health Centre, Montreal, Canada.
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11
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Ombelet S, Ronat JB, Walsh T, Yansouni CP, Cox J, Vlieghe E, Martiny D, Semret M, Vandenberg O, Jacobs J. Clinical bacteriology in low-resource settings: today's solutions. THE LANCET. INFECTIOUS DISEASES 2018. [PMID: 29519767 DOI: 10.1016/s1473-3099(18)30093-8] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Low-resource settings are disproportionately burdened by infectious diseases and antimicrobial resistance. Good quality clinical bacteriology through a well functioning reference laboratory network is necessary for effective resistance control, but low-resource settings face infrastructural, technical, and behavioural challenges in the implementation of clinical bacteriology. In this Personal View, we explore what constitutes successful implementation of clinical bacteriology in low-resource settings and describe a framework for implementation that is suitable for general referral hospitals in low-income and middle-income countries with a moderate infrastructure. Most microbiological techniques and equipment are not developed for the specific needs of such settings. Pending the arrival of a new generation diagnostics for these settings, we suggest focus on improving, adapting, and implementing conventional, culture-based techniques. Priorities in low-resource settings include harmonised, quality assured, and tropicalised equipment, consumables, and techniques, and rationalised bacterial identification and testing for antimicrobial resistance. Diagnostics should be integrated into clinical care and patient management; clinically relevant specimens must be appropriately selected and prioritised. Open-access training materials and information management tools should be developed. Also important is the need for onsite validation and field adoption of diagnostics in low-resource settings, with considerable shortening of the time between development and implementation of diagnostics. We argue that the implementation of clinical bacteriology in low-resource settings improves patient management, provides valuable surveillance for local antibiotic treatment guidelines and national policies, and supports containment of antimicrobial resistance and the prevention and control of hospital-acquired infections.
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Affiliation(s)
- Sien Ombelet
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium.
| | | | | | - Cedric P Yansouni
- JD MacLean Centre for Tropical Diseases, McGill University Health Centre, Montreal, QC, Canada
| | - Janneke Cox
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Erika Vlieghe
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Department of General Internal Medicine, Infectious and Tropical Diseases, Antwerp University Hospital, Antwerp, Belgium; Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Delphine Martiny
- Department of Microbiology, LHUB-ULB, Pôle Hospitalier Universitaire de Bruxelles, Brussels, Belgium
| | - Makeda Semret
- JD MacLean Centre for Tropical Diseases, McGill University Health Centre, Montreal, QC, Canada; St Mary's Hospital Centre, Montreal, QC, Canada
| | - Olivier Vandenberg
- Department of Microbiology, LHUB-ULB, Pôle Hospitalier Universitaire de Bruxelles, Brussels, Belgium; Center for Environmental Health and Occupational Health, Public Health School, Université Libre de Bruxelles, Brussels, Belgium
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
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12
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Robinson ML, Manabe YC. Reducing Uncertainty for Acute Febrile Illness in Resource-Limited Settings: The Current Diagnostic Landscape. Am J Trop Med Hyg 2017; 96:1285-1295. [PMID: 28719277 DOI: 10.4269/ajtmh.16-0667] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AbstractDiagnosing the cause of acute febrile illness in resource-limited settings is important-to give the correct antimicrobials to patients who need them, to prevent unnecessary antimicrobial use, to detect emerging infectious diseases early, and to guide vaccine deployment. A variety of approaches are yielding more rapid and accurate tests that can detect more pathogens in a wider variety of settings. After decades of slow progress in diagnostics for acute febrile illness in resource-limited settings, a wave of converging advancements will enable clinicians in resource-limited settings to reduce uncertainty for the diagnosis of acute febrile illness.
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Affiliation(s)
- Matthew L Robinson
- Division of Infectious Disease, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Yukari C Manabe
- Division of Infectious Disease, Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland
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13
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Storey HL, Huang Y, Crudder C, Golden A, de los Santos T, Hawkins K. A Meta-Analysis of Typhoid Diagnostic Accuracy Studies: A Recommendation to Adopt a Standardized Composite Reference. PLoS One 2015; 10:e0142364. [PMID: 26566275 PMCID: PMC4643909 DOI: 10.1371/journal.pone.0142364] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/21/2015] [Indexed: 01/09/2023] Open
Abstract
Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS) can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates.
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Affiliation(s)
- Helen L. Storey
- Diagnostics Program, PATH, Seattle, Washington, United States of America
- * E-mail:
| | - Ying Huang
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Chris Crudder
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Allison Golden
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Tala de los Santos
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Kenneth Hawkins
- Diagnostics Program, PATH, Seattle, Washington, United States of America
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14
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Andrews JR, Ryan ET. Diagnostics for invasive Salmonella infections: Current challenges and future directions. Vaccine 2015; 33 Suppl 3:C8-15. [PMID: 25937611 DOI: 10.1016/j.vaccine.2015.02.030] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/03/2015] [Accepted: 02/08/2015] [Indexed: 10/23/2022]
Abstract
Invasive Salmonellosis caused by Salmonella enterica serotype Typhi or Paratyphi A, B, C, or invasive non-typhoidal Salmonella serotypes, is an immensely important disease cluster for which reliable, rapid diagnostic tests are not available. Blood culture remains the gold standard but is insensitive, slow, and resource-intensive. Existing molecular diagnostics have poor sensitivity due to the low organism burden in bodily fluids. Commercially available serologic tests for typhoidal Salmonella have had limited sensitivity and specificity. In high burden, resource-limited settings, reliance on clinical diagnosis or inaccurate tests often results in frequent, unnecessary treatment, which contributes selective pressure for the emergence of antimicrobial resistance. This practice also results in inadequate therapy for other etiologies of acute febrile illnesses, including leptospirosis and rickettsial infections. A number of novel serologic, molecular, transcriptomic and metabolomic approaches to diagnostics are under development. Target product profiles that outline specific needs may focus development and investment, and establish benchmarks for accuracy, cost, speed, and portability of new diagnostics. Of note, a critical barrier to diagnostic assay rollout will be the low cost and low perceived harm of empiric therapy on behalf of providers and patients, which leaves few perceived incentives to utilize diagnostics. Approaches that align incentives with societal goals of limiting inappropriate antimicrobial use, such as subsidizing diagnostics, may be essential for stimulating development and uptake of such assays in resource-limited settings. New diagnostics for invasive Salmonellosis should be developed and deployed alongside diagnostics for alternative etiologies of acute febrile illnesses to improve targeted use of antibiotics.
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Affiliation(s)
- Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, United States.
| | - Edward T Ryan
- Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States.
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15
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Luby SP, Saha S, Andrews JR. Towards sustainable public health surveillance for enteric fever. Vaccine 2015; 33 Suppl 3:C3-7. [PMID: 25912287 DOI: 10.1016/j.vaccine.2015.02.054] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/09/2015] [Accepted: 02/12/2015] [Indexed: 10/23/2022]
Abstract
Enteric fever that results from infection by the typhoidal Salmonellas (Salmonella Typhi and Salmonella Paratyphi A, B and C) is a life-threatening preventable illness. Surveillance of enteric fever is important to understand current burden of disease, to track changes in human health burden from increasing antimicrobial resistance and to assess the impact of efforts to reduce disease burden. Since enteric fever occurs predominantly in low income communities, expensive surveillance is not sustainable. Traditional hospital-based surveillance does not estimate population burden and intensive community-based cohort studies do not capture the severe disease that is crucial to policy decisions. While cohort studies have been considered the gold standard for incidence estimates, the resources required to conduct them are great; as a consequence, estimates of enteric fever burden have been highly geographically and temporally restricted. A hybrid approach combining laboratory diagnosis that is already being conducted in healthcare centers with community-based surveillance of health care facility use offers a low-cost, sustainable approach to generate policy relevant data.
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Affiliation(s)
- Stephen P Luby
- Infectious Diseases and Geographic Medicine, Stanford University, Stanford, CA, United States.
| | - Samir Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Jason R Andrews
- Infectious Diseases and Geographic Medicine, Stanford University, Stanford, CA, United States
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16
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Jones C, Darton TC, Pollard AJ. Why the development of effective typhoid control measures requires the use of human challenge studies. Front Microbiol 2014; 5:707. [PMID: 25566221 PMCID: PMC4267421 DOI: 10.3389/fmicb.2014.00707] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 11/27/2014] [Indexed: 01/21/2023] Open
Affiliation(s)
- Claire Jones
- Oxford Vaccine Group, Department of Paediatrics, National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford Oxford, UK
| | - Thomas C Darton
- Oxford Vaccine Group, Department of Paediatrics, National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford Oxford, UK
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford Oxford, UK
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17
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Bwambok DK, Christodouleas DC, Morin SA, Lange H, Phillips ST, Whitesides GM. Adaptive use of bubble wrap for storing liquid samples and performing analytical assays. Anal Chem 2014; 86:7478-85. [PMID: 24983331 DOI: 10.1021/ac501206m] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This paper demonstrates that the gas-filled compartments in the packing material commonly called "bubble wrap" can be repurposed in resource-limited regions as containers to store liquid samples, and to perform bioanalyses. The bubbles of bubble wrap are easily filled by injecting the samples into them using a syringe with a needle or a pipet tip, and then sealing the hole with nail hardener. The bubbles are transparent in the visible range of the spectrum, and can be used as "cuvettes" for absorbance and fluorescence measurements. The interiors of these bubbles are sterile and allow storage of samples without the need for expensive sterilization equipment. The bubbles are also permeable to gases, and can be used to culture and store micro-organisms. By incorporating carbon electrodes, these bubbles can be used as electrochemical cells. This paper demonstrates the capabilities of the bubbles by culturing E. coli, growing C. elegans, measuring glucose and hemoglobin spectrophotometrically, and measuring ferrocyanide electrochemically, all within the bubbles.
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Affiliation(s)
- David K Bwambok
- Department of Chemistry & Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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18
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Nam S, Kim MJ, Park M, Kim N, Lee YJ, Lee GC. Detection of coliforms in drinking water using skin patches: a rapid, reliable method that does not require an external energy source. Am J Trop Med Hyg 2014; 90:283-7. [PMID: 24420783 DOI: 10.4269/ajtmh.13-0349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The detection of coliforms requires incubation in a laboratory, generally powered using electricity. In many parts of the developing world, however, external energy sources such as electricity are not readily available. To develop a fast, reliable method for detecting coliforms in water without an external energy source, we assessed the efficacy of six test kits for the identification of coliforms in water samples. To assess the possibility of using body temperature as the sole source of heat for incubation, bacterial samples were then mixed with the enzymatic test kit reagent and attached to the human body surface using a patch system. The patches were attached to the bodies of volunteers for 24 hours and the practicality and accuracy of the patches were assessed. Coliforms were detected within 24 hours in all patches. This innovation will facilitate the testing of water quality by researchers and by economically disadvantaged people without electricity.
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Affiliation(s)
- Sehee Nam
- Water Analysis and Research Center, K-water, Daejeon, Republic of Korea; Korean Minjok Leadership Academy, Hoengseong, Gangwon, Republic of Korea
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Abstract
PURPOSE OF REVIEW Infection caused by ingestion of human-restricted Salmonella enterica serovars Typhi and Paratyphi predominantly affects the most impoverished sections of society. In this review, we describe recent advances made in estimating the burden of illness and the important role improved diagnostic tests may have in controlling infection and report the development of a new human challenge model of typhoid infection. RECENT FINDINGS Typhoid continues to be a major cause of morbidity, particularly in children and young adults in south east Asia, although accurate assessments are still hindered by the lack of reliable surveillance data. Recent reports of high rates of infection in Africa and the dominance of paratyphoid in several geographic areas are of particular concern. Diagnosis of enteric fever remains frustrated by the nonspecific clinical presentation of cases and the lack of test sensitivity. Methods to improve diagnostic accuracy are hindered by the incomplete understanding of immunobiological mechanisms of infection and lack of a suitable animal infection model. SUMMARY Enteric fever is a major global problem, the burden of which has only partially been recognized. Control strategies utilizing cheap accurate diagnostics and effective vaccines are urgently required, and their development should be accelerated by the use of a human challenge model.
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