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Background The current coronavirus infectious disease 2019 (COVID-19) pandemic has caused unexpected pressure on medical supplies, interrupting supply chains and increasing prices. The supply of antiviral filters which form an essential part of the ventilator circuit have been affected by these issues. Three-dimensional (3D) printing may provide a solution to some of these issues. Methods We designed and tested 3D printed heat and moisture exchange (HME) and antiviral casing. For each casing we tested two different filter materials derived from a sediment water filter cartridge or 1.5-μm glass fiber filter paper. A polyurethane sponge was used for the HME. Each design was tested for circuit leak, circuit compliance, peak inspiratory pressure and casing integrity using methylene blue dye. Results We designed, produced, and tested two different types of antiviral filters with six different internal configurations. Overall, we tested 10 modified filter designs and compared them with the original commercial filter. Except for the combination of 1.5-μm filter paper and 5 mm sponge peak inspiratory pressure and circuit compliance of the filters produced were within the operating limits of the ventilator. All In addition, all filters passed the dye test. Conclusions Our filter may be of particular importance to those working in low middle-income countries unable to compete with stronger economies. Our design relies on products available outside the healthcare supply chain, much of which can be purchased in grocery stores, hardware stores, or industrial and academic institutions. We hope that these HMEs and viral filters may be beneficial to clinicians who face critical supply chain issues during the COVID-19 pandemic.

This paper discusses the ways in which 2009 novel swine‐origin influenza A (H1N1) was announced and resonated with current pandemic anxieties. In particular, the US Centers for Disease Control and Prevention (CDC) are used as a lens through which recent pandemic anxieties can be analysed and understood. This entails a closer look at the securitisation of public health and the challenges and struggles this may have caused within public health agencies. In that light, CDC' formal entanglement with global health security and its announcement of the H1N1 pandemic are interpreted, followed by an ethnographically informed focus on various people who were engaged in the H1N1 emergency response and their practices and practical struggles in the face of pandemic anxiety.

Pesticide exposure in Ecuador's banana industry reflects political economic and ecological processes that interact across scales to affect human health. We use this case study to illustrate opportunities for applying political ecology of health scholarship in the burgeoning field of global health. Drawing on an historical literature review and ethnographic data collected in Ecuador's El Oro province, we present three main areas where a political ecological approach can enrich global health scholarship: perceptive characterization of multi-scalar and ecologically entangled pathways to health outcomes; critical analysis of discursive dynamics such as competing scalar narratives; and appreciation of the environment-linked subjectivities and emotions of people experiencing globalized health impacts. Rapprochement between these fields may also provide political ecologists with access to valuable empirical data on health outcomes, venues for engaged scholarship, and opportunities to synthesize numerous insightful case studies and discern broader patterns.La exposición a agroquímicos en la industria bananera del Ecuador evidencia procesos de ecología y economía política interactuando en diferentes escalas y que terminan afectando a la salud humana. Este estudio de caso ilustra como la ecología política de la salud puede aportar al creciente campo de la salud global. A partir de una revisión histórica de literatura y de datos etnográficos recopilados en la provincia de El Oro, Ecuador, presentamos tres áreas principales donde la perspectiva de ecología política puede enriquecer el campo de la salud global: caracterización perspicaz de trayectorias multi‐escalares y ecológicamente relacionadas que afectan a la salud; valoración crítica de dinámicas discursivas tales como las narrativas escalares contrapuestas; y apreciación de subjetividades y emociones relacionadas con el ambiente entre personas que viven impactos de salud global. El acercamiento entre estos dos campos también puede proporcionar a los ecólogos políticos acceso a valiosos datos empíricos sobre salud, espacios para la praxis y oportunidades para sintetizar numerosos estudios de casos perspicaces para discernir patrones más amplios.

In this Feature, the most recent developments as well as “pros and cons” in smartphone sensing, which have been developed using various functional nanoparticles in paper-based sensing systems, will be discussed. Additionally, smart phone sensing and POC combination as a potential tool that opens a gate for knowledge flow “from lab scale data to public use” will be evaluated.

Where malaria surveillance and health care is inadequate, iron supplements given without food can increase the severity of malarial infections. The likely explanation is that the rate of iron influx into the plasma from high-dose oral supplements exceeds the rate of iron binding to transferrin and a quantity of non-transferrin-bound iron (NTBI) is formed. It is proposed that NTBI increases the intensity of malarial infections by increasing the sequestration of malaria-infected red cells in the capillaries of the brain and intestine, causing more cerebral malaria and further increasing the permeability of the intestinal barrier to the passage of pathogens. Bacteremia is frequently reported in children with severe malaria. At the same time, high iron doses stimulate the growth of pathogenic bacteria in the stool, further increasing the potential for bacteremia. The normal immune response to malaria, as well as other infections and inflammatory disorders, is to prevent further microbial growth by stimulating hepcidin synthesis and preventing the passage of iron into the plasma. Iron absorption is decreased and the efficacy of the iron interventions would be expected to be lower in the presence of infections.

Background Traditional methods of detecting Leishmania from cutaneous lesions involve invasive diagnostic procedures, such as scrapings, which cause discomfort, require technical expertise, and carry risks of invasive procedures. We compared the performance of 2 novel, molecular-based non-invasive methods for the diagnosis of cutaneous leishmaniasis (CL). Methods Consecutive patients presenting to the Leishmania Clinic at the Hospital Nacional Cayetano Heredia were enrolled. PCR was performed on filter paper lesion impressions (FPLIs), cytology brushes, and lancets for detection of Leishmania DNA. Smears from lesion scrapings and leishmanin skin test were also performed. Outcome measures were sensitivity and specificity. Composite reference standard was any 2 of 5 tests positive. Species identification was performed by PCR assays of positive specimens. Results Ninety patients with 129 lesions were enrolled, 117 of which fulfilled reference criteria for a diagnosis of CL. Of these 117 lesions, 113 were positive by PCR of lancets used for lesion scrapings versus 116 by PCR of FPLIs (p = 0.930) or 116 by PCR of cytology brushes (p = 0.930). Sensitivity and specificity of PCR on lancets were 96.6% [95% CI 93.3–99.9%] and 100%, respectively. Sensitivity and specificity of FPLI PCR were 99.1% [95% CI 97.4–100%] and 100%, respectively. Sensitivity and specificity of cytology brush PCR were 99.1% [95% CI 97.4–100%] and 100%, respectively. Giemsa-stained lesion smear and leishmanin skin test had inferior sensitivities at 47.9% [95% CI 38.9–57.0%] and 82.3% [95% CI 73.9–90.7%], respectively, compared to PCR of invasive or non-invasive specimens (p

Here we describe an ultra-low-cost origami-based approach for large-scale manufacturing of microscopes, specifically demonstrating brightfield, darkfield, and fluorescence microscopes. Merging principles of optical design with origami enables high-volume fabrication of microscopes from 2D media. Flexure mechanisms created via folding enable a flat compact design. Structural loops in folded paper provide kinematic constraints as a means for passive self-alignment. This light, rugged instrument can survive harsh field conditions while providing a diversity of imaging capabilities, thus serving wide-ranging applications for cost-effective, portable microscopes in science and education.