Project description:Background: Antibodies against SARS-CoV-2 can be detected by various testing platforms, but a detailed understanding of assay performance is critical. Methods: We developed and validated a simple enzyme-linked immunosorbent assay (ELISA) to detect IgG binding to the receptor-binding domain (RBD) of SARS-CoV-2, which was then applied for surveillance. ELISA results were compared to a set of complimentary serologic assays using a large panel of clinical research samples. Results: The RBD ELISA exhibited robust performance in ROC curve analysis (AUC> 0.99; Se = 89%, Sp = 99.3%). Antibodies were detected in 23/353 (6.5%) healthcare workers, 6/9 RT-PCR-confirmed mild COVID-19 cases, and 0/30 non-COVID-19 cases from an ambulatory site. RBD ELISA showed a positive correlation with neutralizing activity (p = <0.0001, R 2 = 0.26). Conclusions: We applied a validated SARS-CoV-2-specific IgG ELISA in multiple contexts and performed orthogonal testing on samples. This study demonstrates the utility of a simple serologic assay for detecting prior SARS-CoV-2 infection, particularly as a tool for efficiently testing large numbers of samples as in population surveillance. Our work also highlights that precise understanding of SARS-CoV-2 infection and immunity at the individual level, particularly with wide availability of vaccination, may be improved by orthogonal testing and/or more complex assays such as multiplex bead assays.
Project description:ObjectiveTo inform quarantine and contact-tracing policies concerning re-positive cases-cases testing positive among those recovered.Materials and methodsWe systematically reviewed and appraised relevant literature from PubMed and Embase for the extent of re-positive cases and their epidemiological characteristics.ResultsIn 90 case reports/series, a total of 276 re-positive cases were found. Among confirmed reinfections, 50% occurred within 90 days from recovery. Four reports related onward transmission. In thirty-five observational studies, rate of re-positives ranged from zero to 50% with no onward transmissions reported. In eight reviews, pooled recurrence rate ranged from 12% to 17.7%. Probability of re-positive increased with several factors.ConclusionRecurrence of a positive SARS-CoV-2 test is commonly reported within the first weeks following recovery from a first infection.
Project description:Lockdowns to contain the spread of the SARS-CoV-2 have disrupted routines and behaviors, which could lead to a worsening of lifestyle and an increase in the burden of non-communicable diseases. This study aimed to describe the changes in physical activity, diet, alcohol drinking, and cigarette smoking during lockdown. A self-administered online survey addressing adults living in a province in northern Italy was advertised through websites and social media. Citizens could access the survey in anonymity from 4 May until 15 June 2020. A total of 1826 adults completed the survey, with a worsening of physical activity (35.1%), diet (17.6%), alcohol drinking (12.5%), and cigarette smoking (7.7%) reported. In contrast, 33.5% reported an improvement in diet, 12.6% in alcohol drinking, 5.3% in physical activity and 4.1% in cigarette smoking. Female sex, young adult age, suspension of work activity, and symptoms of psychological distress were the factors associated with a greater likelihood of change, which was frequently for the worse. Lockdown had an impact on lifestyle, with some net beneficial effects on diet and mostly negative effects on physical activity. Public health measures should be implemented to avoid long-term negative effects of the lockdown, supporting individuals more prone to change for the worse.
Project description:Wastewater surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has garnered extensive public attention during the coronavirus disease pandemic as a proposed complement to existing disease surveillance systems. Over the past year, methods for detection and quantification of SARS-CoV-2 viral RNA in untreated sewage have advanced, and concentrations in wastewater have been shown to correlate with trends in reported cases. Despite the promise of wastewater surveillance, for these measurements to translate into useful public health tools, bridging the communication and knowledge gaps between researchers and public health responders is needed. We describe the key uses, barriers, and applicability of SARS-CoV-2 wastewater surveillance for supporting public health decisions and actions, including establishing ethics consideration for monitoring. Although wastewater surveillance to assess community infections is not a new idea, the coronavirus disease pandemic might be the initiating event to make this emerging public health tool a sustainable nationwide surveillance system, provided that these barriers are addressed.
Project description:BackgroundDespite improving trends, countries in Europe continue to face public-health challenges. This study investigated the priorities of stakeholders for research to meet these challenges.MethodsPublic-health research includes population-level and health-system research, but not clinical or biomedical research. The study drew on data from three surveys undertaken through collaboration in SPHERE (Strengthening Public Health Research in Europe). There was participation of ministries in 18 of 28 (64% response) European countries, from 22 of 39 (56% response) member national associations of the European Public Health Association, and from 80 civil society health organisations (53% of members of the European Public Health Alliance)ResultsPublic-health research fields included disease control, health promotion and health services. Ministries of health, rather than ministries of science or education, mostly took responsibility for public-health research: they reported varied but well-defined areas for research in relation to national health plans and programmes. National public health associations reported research priorities across most fields of public health, although with some European regional differences. Civil society health organisations prioritised health promotion research nationally, but also health services research internationally. There was less research reported on methods, such as modelling and economic analysis, wider determinants of health, and public-health interventions.ConclusionSystematic collaboration between stakeholders across European countries would enhance knowledge and promote innovation to address contemporary public-health challenges.
Project description:The emergence of SARS-CoV-2 variants has exacerbated the COVID-19 global health crisis. Thus far, all variants carry mutations in the spike glycoprotein, which is a critical determinant of viral transmission being responsible for attachment, receptor engagement and membrane fusion, and an important target of immunity. Variants frequently bear truncations of flexible loops in the N-terminal domain (NTD) of spike; the functional importance of these modifications has remained poorly characterised. We demonstrate that NTD deletions are important for efficient entry by the Alpha and Omicron variants and that this correlates with spike stability. Phylogenetic analysis reveals extensive NTD loop length polymorphisms across the sarbecoviruses, setting an evolutionary precedent for loop remodelling. Guided by these analyses, we demonstrate that variations in NTD loop length, alone, are sufficient to modulate virus entry. We propose that variations in NTD loop length act to fine-tune spike; this may provide a mechanism for SARS-CoV-2 to navigate a complex selection landscape encompassing optimisation of essential functionality, immune driven antigenic variation and ongoing adaptation to a new host.
Project description:The U.S. FDA approval of PAXLOVID, a combination therapy of nirmatrelvir and ritonavir has significantly boosted our morale in fighting the COVID-19 pandemic. Nirmatrelvir is an inhibitor of the main protease (MPro) of SARS-CoV-2. Since many SARS-CoV-2 variants that resist vaccines and antibodies have emerged, a concern of acquired viral resistance to nirmatrelvir naturally arises. Here, possible mutations in MPro to confer viral evasion of nirmatrelvir are analyzed and discussed from both evolutionary and structural standpoints. The analysis indicates that those mutations will likely reside in the whole aa45-51 helical region and residues including M165, L167, P168, R188, and Q189. Relevant mutations have also been observed in existing SARS-CoV-2 samples. Implications of this analysis to the fight against future drug-resistant viral variants and the development of broad-spectrum antivirals are discussed as well.