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BackgroundAcute respiratory infections (ARIs), primarily pneumonia, are the leading infectious cause of under-5 mortality worldwide. Manually counting respiratory rate (RR) for 60 seconds using an ARI timer is commonly practiced by community health workers to detect fast breathing, an important sign of pneumonia. However, correctly counting breaths manually and classifying the RR is challenging, often leading to inappropriate treatment. A potential solution is to introduce RR counters, which count and classify RR automatically. ObjectiveThis study aims to determine how the RR count of an Automated Respiratory Infection Diagnostic Aid (ARIDA) agrees with the count of an expert panel of pediatricians counting RR by reviewing a video of the child’s chest for 60 seconds (reference standard), for children aged younger than 5 years with cough and/or difficult breathing. MethodsA cross-sectional study aiming to enroll 290 children aged 0 to 59 months presenting to pediatric in- and outpatient departments at a teaching hospital in Addis Ababa, Ethiopia, was conducted. Enrollment occurred between April and May 2017. Once enrolled, children participated in at least one of three types of RR evaluations: (1) agreement—measure the RR count of an ARIDA in comparison with the reference standard, (2) consistency—measure the agreement between two ARIDA devices strapped to one child, and (3) RR fluctuation—measure RR count variability over time after ARIDA attachment as measured by a manual count. The agreement and consistency of expert clinicians (ECs) counting RR for the same child with the Mark 2 ARI timer for 60 seconds was also measured in comparison with the reference standard. ResultsPrimary outcomes were (1) mean difference between the ARIDA and reference standard RR count (agreement) and (2) mean difference between RR counts obtained by two ARIDA devices started simultaneously (consistency). ConclusionsStudy strengths included the design allowing for comparison between both ARIDA and the EC with the reference standard RR count. A limitation is that exactly the same set of breaths were not compared between ARIDA and the reference standard since ARIDA can take longer than 60 seconds to count RR. Also, manual RR counting, even when aided by a video of the child’s chest movements, is subject to human error and can result in low interrater reliability. Further work is needed to reach global consensus on the most appropriate reference standard and an acceptable level of agreement to provide ministries of health with evidence to make an informed decision on whether to scale up new automated RR counters. Trial RegistrationClinicalTrials.gov NCT03067558; https://clinicaltrials.gov/ct2/show/NCT03067558 International Registered Report Identifier (IRRID)RR1-10.2196/16531

Sensitive field-deployable diagnostic tests can assist malaria programs in achieving elimination. The performance of a new Alere™ Malaria Ag P.f Ultra Sensitive rapid diagnostic test (uRDT) was compared with the currently available SD Bioline Malaria Ag P.f RDT in blood specimens from asymptomatic individuals in Nagongera, Uganda, and in a Karen Village, Myanmar, representative of high- and low-transmission areas, respectively, as well as in pretreatment specimens from study participants from four Plasmodium falciparum-induced blood-stage malaria (IBSM) studies. A quantitative reverse transcription PCR (qRT-PCR) and a highly sensitive enzyme-linked immunosorbent assay (ELISA) test for histidine-rich protein II (HRP2) were used as reference assays. The uRDT showed a greater than 10-fold lower limit of detection for HRP2 compared with the RDT. The sensitivity of the uRDT was 84% and 44% against qRT-PCR in Uganda and Myanmar, respectively, and that of the RDT was 62% and 0% for the same two sites. The specificities of the uRDT were 92% and 99.8% against qRT-PCR for Uganda and Myanmar, respectively, and 99% and 99.8% against the HRP2 reference ELISA. The RDT had specificities of 95% and 100% against qRT-PCR for Uganda and Myanmar, respectively, and 96% and 100% against the HRP2 reference ELISA. The uRDT detected new infections in IBSM study participants 1.5 days sooner than the RDT. The uRDT has the same workflow as currently available RDTs, but improved performance characteristics to identify asymptomatic malaria infections. The uRDT may be a useful tool for malaria elimination strategies.

Corneal blindness accounts for 5.1% of visual deficiency and is the fourth leading cause of blindness globally. An additional 1.5–2 million people develop corneal blindness each year, including many children born with or who later develop corneal infections. Over 90% of corneal blind people globally live in low- and middle-income regions (LMIRs), where corneal ulcers are approximately 10-fold higher compared to high-income countries. While corneal transplantation is an effective option for patients in high-income countries, there is a considerable global shortage of corneal graft tissue and limited corneal transplant programs in many LMIRs. In situ tissue regeneration aims to restore diseases or damaged tissues by inducing organ regeneration. This can be achieved in the cornea using biomaterials based on extracellular matrix (ECM) components like collagen, hyaluronic acid, and silk. Solid corneal implants based on recombinant human collagen type III were successfully implanted into patients resulting in regeneration of the corneal epithelium, stroma, and sub-basal nerve plexus. As ECM crosslinking and manufacturing methods improve, the focus of biomaterial development has shifted to injectable, in situ gelling formulations. Collagen, collagen-mimetic, and gelatin-based in situ gelling formulas have shown the ability to repair corneal wounds, surgical incisions, and perforations in in-vivo models. Biomaterial approaches may not be sufficient to treat inflammatory conditions, so other cell-free therapies such as treatment with tolerogenic exosomes and extracellular vesicles may improve treatment outcomes. Overall, many of the technologies described here show promise as future medical devices or combination products with cell or drug-based therapies. In situ tissue regeneration, particularly with liquid formulas, offers the ability to triage and treat corneal injuries and disease with a single regenerative solution, providing alternatives to organ transplantation and improving patient outcomes. [ABSTRACT FROM AUTHOR]

Aim: Pneumonia is the leading infectious cause of death among children under five globally. Many pneumonia deaths result from inappropriate treatment due to misdiagnosis of signs and symptoms. This study aims to identify whether health extension workers (HEWs) in Ethiopia, using an automated multimodal device (Masimo Rad-G), adhere to required guidelines while assessing and classifying under five children with cough or difficulty breathing and to understand device acceptability.Methods: A cross-sectional study was conducted in three districts of Southern Nations, Nationalities, and Peoples' Region, Ethiopia. Between September and December 2018, 133 HEWs were directly observed using Rad-G while conducting 599 sick child consultations. Usability was measured as adherence to the World Health Organization requirements to assess fast breathing and device manufacturer instructions for use. Acceptability was assessed using semi-structured interviews with HEWs, first-level health facility workers and caregivers.Results: Adherence using the Rad-G routinely for 2 months was 85.3% (95% CI 80.2, 89.3). Health workers and caregivers stated a preference for Rad-G. Users highlighted a number of device design issues.Conclusion: While demonstrating high levels of acceptability and usability, the device modifications to consider include better probe fit, improved user interface with exclusive age categories and simplified classification outcomes. [ABSTRACT FROM AUTHOR]

Aim: Manually counting respiratory rate (RR) is commonly practiced by community health workers to detect fast breathing, an important sign of childhood pneumonia. Correctly counting and classifying breaths manually is challenging, often leading to inappropriate treatment. This study aimed to determine the usability of a new automated RR counter (ChARM) by health extension workers (HEWs), and its acceptability to HEWs, first-level health facility workers (FLHFWs) and caregivers in Ethiopia.Methods: A cross-sectional study was conducted in one region of Ethiopia between May and August 2018. A total of 131 HEWs were directly observed conducting 262 sick child consultations after training and 337 after 2 months. Usability was measured as adherence to the WHO requirements to assess fast breathing and device manufacturer instructions for use (IFU). Acceptability was measured through semi-structured interviews.Results: After 2 months, HEWs were shown to adhere to the requirements in 74.6% consultations; an increase of 18.6% after training (P < .001). ChARM is acceptable to users and caregivers, with HEWs suggesting that ChARM increased client flow and stating a willingness to use ChARM in future.Conclusion: Further research on the performance, cost-effectiveness and implementation of this device is warranted to inform policy decisions in countries with a high childhood pneumonia burden. [ABSTRACT FROM AUTHOR]

Aim: Pneumonia is the leading cause of child death after the neonatal period, resulting from late care seeking and inappropriate treatment. Diagnosis involves counting respiratory rate (RR); however, RR counting remains challenging for health workers and miscounting, and misclassification of RR is common. We evaluated the usability of a new automated RR counter, the Philips Children's Respiratory Monitor (ChARM), to Female Community Health Volunteers (FCHVs), and its acceptability to FCHVs and caregivers in Nepal., Methods: A cross-sectional study was conducted in Jumla district, Nepal. About 133 FCHVs were observed between September and December 2018 when using ChARM during 517 sick child consultations, 264 after training and 253 after 2 months of routine use of ChARM. Acceptability of the ChARM was explored using semi-structured interviews., Results: FCHV adherence to guidelines after 2 months of using ChARM routinely was 52.8% (95% CI 46.6-58.9). The qualitative findings suggest that ChARM is acceptable to FCHVs and caregivers; however, capacity constraints such as older age and low literacy and impacted device usability were mentioned., Conclusion: Further research on the performance, cost-effectiveness and implementation feasibility of this device is recommended, especially among low-literate CHWs., (© 2019 Malaria Consortium. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)

Many infectious diseases, as well as some cancers, that affect global health are most accurately diagnosed through nucleic acid amplification and detection. There is a great need to simplify nucleic acid-based assay systems for use in global health in low-resource settings as well as in settings that do not have convenient access to laboratory staff and equipment such as doctors' offices and home care settings. In developing countries, unreliable electric power, inadequate supply chains, and lack of maintenance for complex diagnostic instruments are all common infrastructure shortfalls. Many elements of instrument-free, disposable, nucleic acid amplification assays have been demonstrated in recent years. However, the problem of instrument-free, low-cost, temperature-controlled chemical heating remains unsolved. In this paper we present the current status and results of work towards developing disposable, low-cost, temperature-controlled heaters designed to support isothermal nucleic acid amplification assays that are integrated with a two-dimensional paper network. Our approach utilizes the heat generated through exothermic chemical reactions and controls the heat through use of engineered phase change materials to enable sustained temperatures required for nucleic acid amplification. By selecting appropriate exothermic and phase change materials, temperatures can be controlled over a wide range, suitable for various isothermal amplification methods, and maintained for over an hour at an accuracy of +/- 1°C.

Many infectious diseases that affect global health are most accurately diagnosed through nucleic acid amplification and detection. However, existing nucleic acid amplification tests are too expensive and complex for most low-resource settings. The small numbers of centralized laboratories that exist in developing countries tend to be in urban areas and primarily cater to the affluent. In contrast, rural area health care facilities commonly have only basic equipment and health workers have limited training and little ability to maintain equipment and handle reagents. 1 Reliable electric power is a common infrastructure shortfall. In this paper, we discuss a practical approach to the design and development of non-instrumented molecular diagnostic tests that exploit the benefits of isothermal amplification strategies. We identify modular instrument-free technologies for sample collection, sample preparation, amplification, heating, and detection. By appropriately selecting and integrating these instrument-free modules, we envision development of an easy to use, infrastructure independent diagnostic test that will enable increased use of highly accurate molecular diagnostics at the point of care in low-resource settings.

We report on the use of a non-instrumented device for the implementation of a loop-mediated amplification (LAMP) based assay for the select-agent bacterial-wilt pathogen Ralstonia solanacearum race 3 biovar 2. Heat energy is generated within the device by the exothermic hydration of calcium oxide, and the reaction temperature is regulated by storing latent energy at the melting temperature of a renewable lipid-based engineered phase-change material. Endpoint detection of the LAMP reaction is achieved without opening the reaction tube by observing the fluorescence of an innovative FRET-based hybridization probe with a simple custom fluorometer. Non-instrumented devices could maintain reactions near the design temperature of 63°C for at least an hour. Using this approach DNA extracted from the pathogen could be detected at fewer than ten copies within a 25 μL reaction mix, illustrating the potential of these technologies for simple, powerful agricultural diagnostics in the field. Furthermore, the assay was just as reliable when implemented in a tropical environment at 31°C as it was when implemented in an air-conditioned lab maintained at 22°C, illustrating the potential value of the technology for field conditions in the tropics and subtropics.

Contraceptive diaphragms offer a discreet method of pregnancy protection that women can use when needed with no side effects. Incorporating antiretroviral HIV microbicides into such devices may also provide protection against HIV infection. The paper gives a brief outline of the work being conducted by PATH, CONRAD and QUB on the development of a microbicide-releasing SILCS diaphragm. The design, engineering and manufacturing challenges that have been encountered will be discussed, as well as the potential impact such a device could have in the developing world.

We have achieved the first complete, non-instrumented nucleic acid amplification test (NAAT) using a calcium oxide heat source thermally linked to an engineered phase change material. These two components alone maintain a thermal profile suitable for the loop-mediated isothermal amplification assay. Starting with computational fluid dynamics analysis, we identified nominal geometry for the exothermic reaction chamber, phase change material chamber, thermal insulation, and packaging. Using this model, we designed and fabricated an alpha prototype assay platform. We have verified the function of this multi-pathogen-capable platform with both fluorescent and visual turbidity indications using samples spiked with malaria DNA. Both the exothermically heated platform samples and samples heated on a Perkin-Elmer GeneAmp9600 thermocycler were first incubated at 62°C for 45 minutes, then heated to 95°C to terminate enzyme activity, then analyzed. Results from the exothermically heated, non-instrumented platform were comparable to those from the thermocycler. These developments will enable point-of-care diagnostics using accurate NAATs which until now have required a well-equipped laboratory. The aim of this research is to provide pathogen detection with NAAT-level sensitivity in low-resource settings where assays such as immunochromatographic strip tests are successfully used but where there is no access to the infrastructure and logistics required to operate and maintain instrument-based diagnostics.