scholarly journals Usability of Rapid Cholera Detection Device (OmniVis) for Water Quality Workers in Bangladesh: Iterative Convergent Mixed Methods Study

10.2196/22973 ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. e22973
Author(s):  
Theresa L Rager ◽  
Cristian Koepfli ◽  
Wasif A Khan ◽  
Sabeena Ahmed ◽  
Zahid Hayat Mahmud ◽  
...  

Background Cholera poses a significant global health burden. In Bangladesh, cholera is endemic and causes more than 100,000 cases each year. Established environmental reservoirs leave millions at risk of infection through the consumption of contaminated water. The Global Task Force for Cholera Control has called for increased environmental surveillance to detect contaminated water sources prior to human infection in an effort to reduce cases and deaths. The OmniVis rapid cholera detection device uses loop-mediated isothermal amplification and particle diffusometry detection methods integrated into a handheld hardware device that attaches to an iPhone 6 to identify and map contaminated water sources. Objective The aim of this study was to evaluate the usability of the OmniVis device with targeted end users to advance the iterative prototyping process and ultimately design a device that easily integrates into users’ workflow. Methods Water quality workers were trained to use the device and subsequently completed an independent device trial and usability questionnaire. Pretraining and posttraining knowledge assessments were administered to ensure training quality did not confound trial and questionnaire Results Device trials identified common user errors and device malfunctions including incorrect test kit insertion and device powering issues. We did not observe meaningful differences in user errors or device malfunctions accumulated per participant across demographic groups. Over 25 trials, the mean time to complete a test was 47 minutes, a significant reduction compared with laboratory protocols, which take approximately 3 days. Overall, participants found the device easy to use and expressed confidence and comfort in using the device independently. Conclusions These results are used to advance the iterative prototyping process of the OmniVis rapid cholera detection device so it can achieve user uptake, workflow integration, and scale to ultimately impact cholera control and elimination strategies. We hope this methodology will promote robust usability evaluations of rapid pathogen detection technologies in device development.


2020 ◽  
Author(s):  
Theresa L Rager ◽  
Cristian Koepfli ◽  
Wasif A Khan ◽  
Sabeena Ahmed ◽  
Zahid Hayat Mahmud ◽  
...  

BACKGROUND Cholera poses a significant global health burden. In Bangladesh, cholera is endemic and causes more than 100,000 cases each year. Established environmental reservoirs leave millions at risk of infection through the consumption of contaminated water. The Global Task Force for Cholera Control has called for increased environmental surveillance to detect contaminated water sources prior to human infection in an effort to reduce cases and deaths. The OmniVis rapid cholera detection device uses loop-mediated isothermal amplification and particle diffusometry detection methods integrated into a handheld hardware device that attaches to an iPhone 6 to identify and map contaminated water sources. OBJECTIVE The aim of this study was to evaluate the usability of the OmniVis device with targeted end users to advance the iterative prototyping process and ultimately design a device that easily integrates into users’ workflow. METHODS Water quality workers were trained to use the device and subsequently completed an independent device trial and usability questionnaire. Pretraining and posttraining knowledge assessments were administered to ensure training quality did not confound trial and questionnaire RESULTS Device trials identified common user errors and device malfunctions including incorrect test kit insertion and device powering issues. We did not observe meaningful differences in user errors or device malfunctions accumulated per participant across demographic groups. Over 25 trials, the mean time to complete a test was 47 minutes, a significant reduction compared with laboratory protocols, which take approximately 3 days. Overall, participants found the device easy to use and expressed confidence and comfort in using the device independently. CONCLUSIONS These results are used to advance the iterative prototyping process of the OmniVis rapid cholera detection device so it can achieve user uptake, workflow integration, and scale to ultimately impact cholera control and elimination strategies. We hope this methodology will promote robust usability evaluations of rapid pathogen detection technologies in device development.



2019 ◽  
Vol 9 (3) ◽  
pp. 450-459 ◽  
Author(s):  
Amadu Salifu ◽  
Helen M. K. Essandoh ◽  
Afsatou Ndama Traore ◽  
Natasha Potgieter

Abstract Regular monitoring of microbial quality of water used for drinking is an important aspect of public health. Microbiological quality, using a novel microbial water quality test kit – Compartment Bag Test (CBT; AguaGenX, LLC, Chapel Hill, NC, USA), and physical parameters (pH, dissolved oxygen, turbidity, temperature and electrical conductivity) of 94 different water sources used by communities in the Ahenema Kokoben area of Ghana for drinking were tested. Using the WHO drinking water quality risk categories for the presence of Escherichia coli indicator bacteria, only 56% (53/94) of the water sources were safe for drinking, while 29% (27/94) of the water sources were classified as high risk and unsafe for human purposes. Some of the physical parameters were also higher than guideline values and could have been a contributing factor to poor water quality. Overall, the CBT proved to be a reliable alternative to traditional and laboratory-dependent microbial drinking water quality tests which can be easily used by water authorities to make sure that water is safe to drink.



2018 ◽  
Vol 16 (3) ◽  
pp. 359-368 ◽  
Author(s):  
Fatuma Matwewe ◽  
Kate Hyland ◽  
Jacqueline Thomas

Abstract In developing countries, rural water sources have the highest levels of faecal contamination but are the least monitored. Affordable field-based water quality tests are needed. The presence of faecal indicator bacteria can be determined with hydrogen sulphide (H2S) detecting tests, that are inexpensive and simple to make locally. In rural Tanzania, a non-governmental organisation (NGO) designed, produced and evaluated a new H2S water quality test kit. The H2S test results correlated with log10Escherichia coli densities from conventional water quality tests. The production cost was US$ 1.10 and the test retailed for US$ 1.37. In total, 433 tests were sold through local pharmacies and NGOs. Additionally, 165 WaSH education meetings, reaching 3,408 community members, were conducted with the H2S test demonstrated in over half the meetings. Pre- and post-surveys of 294 meeting participants saw an increased reporting of household level water treatment by 24%. The H2S test was widely accepted, with 94% of those surveyed willing to buy the test in the future. International and national guidelines for drinking water monitoring need to be amended to include locally produced H2S water quality tests. This will enable households to monitor their own water sources and make informed choices about water safety and treatment.



2010 ◽  
Vol 7 (s1) ◽  
pp. S428-S432 ◽  
Author(s):  
Ashok Kumar Yadav ◽  
Parveen Khan ◽  
Sanjay K. Sharma

This study deals with the statistical analysis and study of water quality index to assess hardness of groundwater in Todaraisingh tehsil of Tonk district of Rajasthan state. The study has been carried out to examine its suitability for drinking, irrigation and industrial purpose. The presence of problematic salts contains in groundwater due to local pollutants and affected the groundwater quality adversely. The estimated values were compared with drinking water quality standards prescribed by B.I.S. It was found that drinking water is severely polluted with hardness causing salts. This study reveals that people dependent on water sources of the study area are prone to health hazards of contaminated water and quality managements to hardness urgently needed.



Author(s):  
Ashok Sinha ◽  
Ranjan Ganguly ◽  
Ishwar K. Puri

Conventional methods of monitoring and testing water quality involve collection of the sample to be tested and its subsequent analysis in a research laboratory for which some procedures may not be feasible or even accessible under certain field situations. Therefore, next generation sensors are required. Herein, an innovative concept that combines a micromixer and microparticle trap is proposed that should enable more rapid pathogen detection in contaminated water. In it, immunomagnetic separation (a procedure [1,2] that is well practiced in the field of immunochemistry) is scaled down from the benchtop to the microscale. Our design is generic, i.e., design is not limited to the detection of waterborne biological agents, but can be used for other forms of chemical analysis. Testing for waterborne bacteria requires analysis methods that must meet a number of challenging criteria. Time and sensitivity of analysis are the more important limitations. Bacterial detection methods have to be rapid and very sensitive since the presence of even a small pathogenic sample may sometimes constitute an infectious or otherwise harmful dose. Selective detection is also required because small numbers of pathogenic bacteria are often present in a complex biological environment along with many other nonpathogenic organisms. As an example, the infectious dosage of a pathogen such as E. coli O157:H7 or Salmonella is as low as 10 cells and the existing coliform standard for E. coli in water is 4 cells: 100 ml [3].





2021 ◽  
Vol 186 (Supplement_1) ◽  
pp. 801-807
Author(s):  
Nathaniel A Young ◽  
Ryan L Lambert ◽  
Angela M Buch ◽  
Christen L Dahl ◽  
Jackson D Harris ◽  
...  

ABSTRACT Introduction Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic compounds used industrially for a wide variety of applications. These PFAS compounds are very stable and persist in the environment. The PFAS contamination is a growing health issue as these compounds have been reported to impact human health and have been detected in both domestic and global water sources. Contaminated water found on military bases poses a potentially serious health concern for active duty military, their families, and the surrounding communities. Previous detection methods for PFAS in contaminated water samples require expensive and time-consuming testing protocols that limit the ability to detect this important global pollutant. The main objective of this work was to develop a novel detection system that utilizes a biological reporter and engineered bacteria as a way to rapidly and efficiently detect PFAS contamination. Materials and Methods The United States Air Force Academy International Genetically Engineered Machine team is genetically engineering Rhodococcus jostii strain RHA1 to contain novel DNA sequences composed of a propane 2-monooxygenase alpha (prmA) promoter and monomeric red fluorescent protein (mRFP). The prmA promoter is activated in the presence of PFAS and transcribes the mRFP reporter. Results The recombinant R. jostii containing the prmA promoter and mRFP reporter respond to exposure of PFAS by activating gene expression of the mRFP. At 100 µM of perfluorooctanoic acid, the mRFP expression was increased 3-fold (qRT-PCR). Rhodococcus jostii without exposure to PFAS compounds had no mRFP expression. Conclusions This novel detection system represents a synthetic biology approach to more efficiently detect PFAS in contaminated samples. With further refinement and modifications, a similar system could be readily deployed in the field around the world to detect this critical pollutant.



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