Accuracy and ease-of-use of seven point-of-care SARS-CoV-2 antigen-detecting tests: A multi-centre clinical evaluation.

BACKGROUND: Antigen-detecting rapid diagnostic tests (Ag-RDTs) for SARS-CoV-2 are important diagnostic tools. We assessed clinical performance and ease-of-use of seven Ag-RDTs in a prospective, manufacturer-independent, multi-centre cross-sectional diagnostic accuracy study to inform global decision makers. METHODS: Unvaccinated participants suspected of a first SARS-CoV-2 infection were recruited at six sites (Germany, Brazil). Ag-RDTs were evaluated sequentially, with collection of paired swabs for routine reverse transcription polymerase chain reaction (RT-PCR) testing and Ag-RDT testing. Performance was compared to RT-PCR overall and in sub-group analyses (viral load, symptoms, symptoms duration). To understandusability a System Usability Scale (SUS) questionnaire and ease-of-use (EoU) assessment were performed. FINDINGS: 7471 participants were included in the analysis. Sensitivities across Ag-RDTs ranged from 70·4%-90·1%, specificities were above 97·2% for all Ag-RDTs but one (93·1%).Ag-RDTs, Mologic, Bionote, Standard Q, showed diagnostic accuracy in line with WHO targets (> 80% sensitivity, > 97% specificity). All tests showed high sensitivity in the first three days after symptom onset (≥87·1%) and in individuals with viral loads≥ 6 log10SARS-CoV2 RNA copies/mL (≥ 88·7%). Usability varied, with Rapigen, Bionote and Standard Q reaching very good scores; 90, 88 and 84/100, respectively. INTERPRETATION: Variability in test performance is partially explained by variable viral loads in population evaluated over the course of the pandemic. All Ag-RDTs reach high sensitivity early in the disease and in individuals with high viral loads, supporting their role in identifying transmission relevant infections. For easy-to-use tests, performance shown will likely be maintained in routine implementation. FUNDING: Ministry of Science, Research and Arts, State of Baden-Wuerttemberg, Germany, internal funds from Heidelberg University Hospital, University Hospital Charité - Universitätsmedizin Berlin, UK Department of International Development, WHO, Unitaid.

Toxicity of spike fragments SARS-CoV-2 S protein for zebrafish: A tool to study its hazardous for human health?

Despite the significant increase in the generation of SARS-CoV-2 contaminated domestic and hospital wastewater, little is known about the ecotoxicological effects of the virus or its structural components in freshwater vertebrates. In this context, this study evaluated the deleterious effects caused by SARS-CoV-2 Spike protein on the health of Danio rerio, zebrafish. We demonstrated, for the first time, that zebrafish injected with fragment 16 to 165 (rSpike), which corresponds to the N-terminal portion of the protein, presented mortalities and adverse effects on liver, kidney, ovary and brain tissues. The conserved genetic homology between zebrafish and humans might be one of the reasons for the intense toxic effects followed inflammatory reaction from the immune system of zebrafish to rSpike which provoked damage to organs in a similar pattern as happen in severe cases of COVID-19 in humans, and, resulted in 78,6% of survival rate in female adults during the first seven days. The application of spike protein in zebrafish was highly toxic that is suitable for future studies to gather valuable information about ecotoxicological impacts, as well as vaccine responses and therapeutic approaches in human medicine. Therefore, besides representing an important tool to assess the harmful effects of SARS-CoV-2 in the aquatic environment, we present the zebrafish as an animal model for translational COVID-19 research.

Molecular testing and analysis of disease spreading during the emergence of COVID-19 in Macaé, the Brazilian National Capital of Oil.

The Brazilian strategy to overcome the spread of COVID-19 has been particularly criticized due to the lack of a national coordinating effort and an appropriate testing program. Here, a successful approach to control the spread of COVID-19 transmission is described by the engagement of public (university and governance) and private sectors (hospitals and oil companies) in Macaé, state of Rio de Janeiro, Brazil, a city known as the National Oil Capital. In 2020 between the 17th and 38th epidemiological week, over two percent of the 206,728 citizens were subjected to symptom analysis and RT-qPCR testing by the Federal University of Rio de Janeiro, with positive individuals being notified up to 48 h after swab collection. Geocodification and spatial cluster analysis were used to limit COVID-19 spreading in Macaé. Within the first semester after the outbreak of COVID-19 in Brazil, Macaé recorded 1.8% of fatalities associated with COVID-19 up to the 38th epidemiological week, which was at least five times lower than the state capital (10.6%). Overall, considering the successful experience of this joint effort of private and public engagement in Macaé, our data suggest that the development of a similar strategy countrywise could have contributed to a better control of the COVID-19 spread in Brazil. Quarantine decree by the local administration, comprehensive molecular testing coupled to scientific analysis of COVID-19 spreading, prevented the catastrophic consequences of the pandemic as seen in other populous cities within the state of Rio de Janeiro and elsewhere in Brazil.