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A centrifugal microfluidic platform to develop various microfluidic operations – the first of its kind in South Africa – is presented. Rapid and low-cost prototyping of centrifugal microfluidic disc devices, as well as a set-up to test the devices using centrifugal forces, is described. Preliminary results show that various microfluidic operations such as fluidic valving, transportation, and microfluidic droplet generation can be achieved. This work provides a complete centrifugal microfluidic platform and the building blocks on which to develop a variety of microfluidic applications and potential products rapidly and at a low cost.

We review the utility of centrifugal microfluidic technologies applied to point-of-care diagnosis in extremely under-resourced environments. The various challenges faced in these settings are showcased, using areas in India and Africa as examples. Measures for the ability of integrated devices to effectively address point-of-care challenges are highlighted, and centrifugal, often termed CD-based microfluidic technologies, technologies are presented as a promising platform to address these challenges. We describe the advantages of centrifugal liquid handling, as well as the ability of a standard CD player to perform a number of common laboratory tests, fulfilling the role of an integrated lab-on-a-CD. Innovative centrifugal approaches for point-of-care in extremely resource-poor settings are highlighted, including sensing and detection strategies, smart power sources and biomimetic inspiration for environmental control. The evolution of centrifugal microfluidics, along with examples of commercial and advanced prototype centrifugal microfluidic systems, is presented, illustrating the success of deployment at the point-of-care. A close fit of emerging centrifugal systems to address a critical panel of tests for under-resourced clinic settings, formulated by medical experts, is demonstrated. This emphasizes the potential of centrifugal microfluidic technologies to be applied effectively to extremely challenging point-of-care scenarios and in playing a role in improving primary care in resource-limited settings across the developing world.

Growing evidence suggests that ABO blood group may play a role in the immunopathogenesis of SARS‐CoV‐2 infection, with group O individuals less likely to test positive and group A conferring a higher susceptibility to infection and propensity to severe disease. The level of evidence supporting an association between ABO type and SARS‐CoV‐2/COVID‐19 ranges from small observational studies, to genome‐wide‐association‐analyses and country‐level meta‐regression analyses. ABO blood group antigens are oligosaccharides expressed on red cells and other tissues (notably endothelium). There are several hypotheses to explain the differences in SARS‐CoV‐2 infection by ABO type. For example, anti‐A and/or anti‐B antibodies (e.g. present in group O individuals) could bind to corresponding antigens on the viral envelope and contribute to viral neutralization, thereby preventing target cell infection. The SARS‐CoV‐2 virus and SARS‐CoV spike (S) proteins may be bound by anti‐A isoagglutinins (e.g. present in group O and group B individuals), which may block interactions between virus and angiotensin‐converting‐enzyme‐2‐receptor, thereby preventing entry into lung epithelial cells. ABO type‐associated variations in angiotensin‐converting enzyme‐1 activity and levels of von Willebrand factor (VWF) and factor VIII could also influence adverse outcomes, notably in group A individuals who express high VWF levels. In conclusion, group O may be associated with a lower risk of SARS‐CoV‐2 infection and group A may be associated with a higher risk of SARS‐CoV‐2 infection along with severe disease. However, prospective and mechanistic studies are needed to verify several of the proposed associations. Based on the strength of available studies, there are insufficient data for guiding policy in this regard. [ABSTRACT FROM AUTHOR]

Background and Objectives: The International Haemovigilance Network collects aggregate data on complications of blood donation from member haemovigilance systems (HVS). We analysed the data collected in 2006–2016 in order to learn from it and consider future improvements. Materials and Methods: National HVS entered annual data on donation complications and on annual whole blood and apheresis donations in the 'ISTARE' (International Surveillance of Transfusion Adverse Reactions and Events) online database. We calculated national and aggregate donation complication rates. Results: Twenty‐four HVS provided data for 138 country years (CY; median 7 CY, IQR 2–8), covering 155 M donations. The overall complication rate was 6·3/1000 donations and the median country rate 3·2/1000 (IQR 1·1–10·1). Overall and severe complication rates varied considerably between HVS. Vasovagal reactions (VVR) were most commonly reported: 4·6/1000 donations, median country rate 3·1/1000 donations (IQR 0·6–7·7). Rare complications included generalized allergic reaction (0·10/100 000) and major blood vessel injury (category available since 2015; 0·12/100 000). Eighteen HVS reported complications of whole blood donation (WBD) and apheresis separately (89 CY, 101·6 M WBD and 26·3 M apheresis donations). The median country VVR rate was 3·4/1000 WBD (IQR 1·0–9·1) and 1·5/1000 apheresis donations (1·0–4·2). Rates of venepuncture‐related complications tended to be higher for apheresis: the median country rate of reported haematomas was 0·39/1000 WBD (IQR 0·31–1·2) vs. 4·2/1000 apheresis donations (0·69–5·6). Conclusion: International reporting allows HVS to study rates of blood donation complications and capture information about very rare events. The present variability of reporting and severity assessment hampers comparisons between HVS and requires further work. [ABSTRACT FROM AUTHOR]

Background and objectives: Use of convalescent plasma for coronavirus disease 2019 (COVID‐19) treatment has gained interest worldwide. However, there is lack of evidence on its dosing, safety and effectiveness. Until data from clinical studies are available to provide solid evidence for worldwide applicable guidelines, there is a need to provide guidance to the transfusion community and researchers on this emergent therapeutic option. This paper aims to identify existing key gaps in current knowledge in the clinical application of COVID‐19 convalescent plasma (CCP). Materials and methods: The International Society of Blood Transfusion (ISBT) initiated a multidisciplinary working group with worldwide representation from all six continents with the aim of reviewing existing practices on CCP use from donor, product and patient perspectives. A subgroup of clinical transfusion professionals was formed to draft a document for CCP clinical application to identify the gaps in knowledge in existing literature. Results: Gaps in knowledge were identified in the following main domains: study design, patient eligibility, CCP dose, frequency and timing of CCP administration, parameters to assess response to CCP treatment and long‐term outcome, adverse events and CCP application in less‐resourced countries as well as in paediatrics and neonates. Conclusion: This paper outlines a framework of gaps in the knowledge of clinical deployment of CPP that were identified as being most relevant. Studies to address the identified gaps are required to provide better evidence on the effectiveness and safety of CCP use. [ABSTRACT FROM AUTHOR]

Background and objectives: COVID‐19 convalescent plasma (CCP) has been used, predominantly in high‐income countries (HICs) to treat COVID‐19; available data suggest the safety and efficacy of use. We sought to develop guidance for procurement and use of CCP, particularly in low‐ and middle‐income countries (LMICs) for which data are lacking. Materials and methods: A multidisciplinary, geographically representative group of individuals with expertise spanning transfusion medicine, infectious diseases and haematology was tasked with the development of a guidance document for CCP, drawing on expert opinion, survey of group members and review of available evidence. Three subgroups (i.e. donor, product and patient) were established based on self‐identified expertise and interest. Here, the donor and product‐related challenges are summarized and contrasted between HICs and LMICs with a view to guide related practices. Results: The challenges to advance CCP therapy are different between HICs and LMICs. Early challenges in HICs related to recruitment and qualification of sufficient donors to meet the growing demand. Antibody testing also posed a specific obstacle given lack of standardization, variable performance of the assays in use and uncertain interpretation of results. In LMICs, an extant transfusion deficit, suboptimal models of donor recruitment (e.g. reliance on replacement and paid donors), limited laboratory capacity for pre‐donation qualification and operational considerations could impede wide adoption. Conclusion: There has been wide‐scale adoption of CCP in many HICs, which could increase if clinical trials show efficacy of use. By contrast, LMICs, having received little attention, require locally applicable strategies for adoption of CCP. [ABSTRACT FROM AUTHOR]

The development of low‐cost, disposable electrode materials has been at the forefront of sensor technology in recent decades. Paper, offers possibilities for multi‐functional, disposable and economically friendly sensing capabilities and has proved to be a suitable reagent storage and substrate material in paper‐based analytical devices (PADs). In this work, we report a simple inkjet printing procedure on photographic paper for the fabrication of single analyte electrochemical sensors. A three‐electrode system, consisting of a 3 mm diameter working electrode (WE), a counter electrode (CE) and a reference electrode (RE) were prepared by inkjet printing of silver conductive inks for comparison to common commercial screen printed electrode (SPE) brands. In a second step, carbon coating and modification of the working electrode surface with an electrochemically reduced graphene oxide, gold nanoparticle (ERGO‐AuNP) film, to improve electrode sensitivity and selectivity was employed. Improved electron‐transfer kinetics, increased active surface area and enhanced catalytic properties were achieved due to the ERGO‐AuNP layer inclusion. Electrical and topographical characterization of the printed layers was performed in the fabrication process. Printing of Ag−NP ink showed good resistivity (1.8–6.3 Ω) on photographic paper. The prepared printed paper‐based electrodes (PPE) offer a quantitative analysis of Ni(II), based on the accumulation of Ni(dmgH)2 complexes at the modified electrode surface by square‐wave adsorptive cathodic stripping voltammetry (SW‐AdCSV). This study offers the first investigation on the feasibility of adsorptive electrochemical sensing methods at porous cellulose paper‐based substrates. Instrumental parameters including deposition potential and deposition time were optimized for both electrochemical sensors. Improved sensitivities were achieved at the modified integrated electrodes over the unmodified derivate with a limit of detection (LOD) of 32.19 μg L−1 achieved for the ERGO‐AuNP−CC−Ag−PPE. This is well below the EPA and WHO standards of 0.1 mg L−1 or 0.1 ppm for Ni2+ in drinking water. [ABSTRACT FROM AUTHOR]