Comparative Study of Chemosensory Dysfunction in COVID-19 in 2 Geographically Distinct Regions.

OBJECTIVE: To directly compare the prevalence of chemosensory dysfunction (smell and taste) in geographically distinct regions with the same questionnaires. METHODS: A cross-sectional study was performed to evaluate the self-reported symptoms among adults (older than 18 years) who underwent COVID-19 testing at an ambulatory assessment center in Canada and at a hospital in Israel between March 16, 2020, and August 19, 2020. The primary outcome was the prevalence of self-reported chemosensory dysfunction (anosmia/hypomsia and dysgeusia/ageusia). Subgroup analysis was performed to evaluate the prevalence of chemosensory deficits among the outpatients. RESULTS: We identified a total of 350 COVID-19-positive patients (138 Canadians and 212 Israelis). The overall prevalence of chemosensory dysfunction was 47.1%. There was a higher proportion of chemosensory deficits among Canadians compared to Israelis (66.7% vs 34.4%, P < .01). A subgroup analysis for outpatients (never hospitalized) still identified a higher prevalence of chemosensory dysfunction among Canadians compared to Israelis (68.2% vs 36.1%, P < 0.01). A majority of patients recovered their sense of smell after 4 weeks of symptom onset. CONCLUSION: Although the prevalence of chemosensory deficit in COVID-19 was found to be similar to previously published reports, the prevalence can vary significantly across different geographical regions. Therefore, it is important to obtain regionally specific data so that the symptom of anosmia/dysgeusia can be used as a guide for screening for the clinical diagnosis of COVID-19.

Large libraries of single-chain trimer peptide-MHCs enable antigen-specific CD8+ T cell discovery and analysis.

The discovery and characterization of antigen-specific CD8+ T cell clonotypes typically involves the labor-intensive synthesis and construction of peptide-MHC tetramers. We adapt single-chain trimer (SCT) technologies into a high throughput platform for pMHC library generation, showing that hundreds can be rapidly prepared across multiple Class I HLA alleles. We use this platform to explore the impact of peptide and SCT template mutations on protein expression yield, thermal stability, and functionality. SCT libraries were an efficient tool for identifying T cells recognizing commonly reported viral epitopes. We then construct SCT libraries to capture SARS-CoV-2 specific CD8+ T cells from COVID-19 participants and healthy donors. The immunogenicity of these epitopes is validated by functional assays of T cells with cloned TCRs captured using SCT libraries. These technologies should enable the rapid analyses of peptide-based T cell responses across several contexts, including autoimmunity, cancer, or infectious disease.

WHO's Community-Centered Epidemic and Pandemic Information Platform: Hive.

Each epidemic and pandemic is accompanied by an infodemic. The infodemic during the COVID-19 pandemic was unprecedented. Accessing accurate information was difficult and misinformation harmed the pandemic response, the health of individuals and trust in science, governments and societies. WHO is building a community-centered information platform, the Hive, to deliver on the vision of ensuring that all people everywhere have access to the right information, at the right time, in the right format in order to make decisions to protect their health and the health of others. The platform provides access to credible information, a safe space for knowledge-sharing, discussion, and collaborating with others, and a forum to crowdsource solutions to problems. The platform is equipped with many collaboration features, including instant chats, event management, and data analytics tools to generate insights. The Hive platform is an innovative minimum viable product (MVP) that seeks to leverage the complex information ecosystem and the invaluable role communities play to share and access trustworthy health information during epidemics and pandemics.

Novel pro-and eukaryotic expression plasmid expressing omicron antigens delivered via Salmonella elicited MHC class I and II based protective immunity.

The latest omicron variants are emerging with mutations in the receptor binding domain (RBD) that confer immune evasion and resistance against current vaccines. Such variants have raised the peril of future vaccine effectiveness, as leading vaccines target the spike protein. Type-IV hypersensitivity, and other ailments due to the dominant Th1 response by leading vaccines, is also to be resolved. Therefore, vaccine that target diverse SARS-CoV-2 proteins and provide broad-spectrum protection and a balanced Th1 and Th2 response is an indispensable armament against the pandemic. In that prospect, a novel dual expression plasmid pJHL270 was developed and demonstrated the expression of omicron antigens exogenously from Salmonella and endogenously in the host cells. The simultaneous activation of MHC class I and II molecules culminated in a balanced Th1 and Th2 response, which was evident through the upsurge of IgG, IgA antibodies, IgG2a/IgG1 ratio, cytokine responses and CD4+, CD8+ T-lymphocytes. The level of CD44+ cells showed the trigger for Th1 and Th2 balance and memory-cell activation for long-lasting immunity. The level of IFN-γ + cells and neutralizing antibodies signifies the anti-viral response. The vaccine protected the hamsters from BA.5 and BA.2.75 omicron viral-challenge, exhibited a significant reduction in lung viral-load and histopathological lesions. In addition to two-way antigen expression and bilateral immune elicitation, this Salmonella-based vaccine delivery system can be prospectively applied to humans and a broad range of animals as a convenient alternative to viral and chemical vaccine delivery approaches.

The Prevalence of SARS-CoV-2 in Autopsies Surrounding the Time of Pandemic Onset: A Retrospective Review of Cases.

CONTEXT: The first case of coronavirus disease 2019 (COVID-19) in the United States (U.S.) was confirmed in January 2020. Initially, little was known about the epidemiology and clinical course of the disease and diagnostic testing was limited in the U.S. until March/April 2020. Since then, many studies have speculated that SARS-CoV-2 may have pre-existed undiagnosed outside China before the known outbreak. OBJECTIVE: To evaluate the prevalence of SARS-CoV-2 in adult autopsy cases performed just before and during the beginning of the pandemic at our institution, where autopsy was not performed on known COVID-19 cases. DESIGN: We included adult autopsies performed in our institution from 6/1/2019-6/30/2020. Cases were divided into groups based on the likelihood of cause of death being related to COVID-19, presence of a clinical respiratory illness, and histologic findings of pneumonia. Archived formalin-fixed-paraffin-embedded lung tissue of all COVID-possible cases and COVID-unlikely cases with pneumonia were tested for the SARS-CoV-2 RNA, using Centers for Disease Control and Prevention 2019-nCoV-Real-Time Reverse Transcription polymerase chain reaction (qRT-PCR). RESULTS: Eighty-eight cases were identified, and among those, 42/88 (48%) cases were considered COVID-possible cause of death with 24/42 (57%) showing respiratory illness and/or pneumonia. COVID-19 as cause of death was considered unlikely in 46/88 (52%) with 34/46 (74%) showing no respiratory illness or pneumonia. SARS-CoV-2 qRT-PCR was performed on a total of 49 cases; 42 COVID-possible and seven COVID-unlikely with pneumonia, and all cases were negative (0/49). CONCLUSIONS: Our data suggests that autopsied patients in our community who died between 6/1/2019-6/30/2020 without known COVID-19 were unlikely to have had subclinical and/or undiagnosed COVID-19 infection.

Family satisfaction with intensive care unit communication during the COVID-19 pandemic: a prospective multicentre Australian study Family Satisfaction - COVID ICU.

BACKGROUND: Virtual communication has become common practice during the coronavirus disease 2019 (COVID-19) pandemic because of visitation restrictions. AIMS: The authors aimed to evaluate overall family satisfaction with the intensive care unit (FS-ICU) care involving virtual communication strategies during the COVID-19 pandemic period. METHODS: In this prospective multicentre study involving three metropolitan hospitals in Melbourne, Australia, the next of kin (NOK) of all eligible ICU patients between 1 July 2020 and 31 October 2020 were requested to complete an adapted version of the FS-ICU 24-questionnaire. Group comparisons were analysed and calculated for family satisfaction scores: ICU/care (satisfaction with care), FS-ICU/dm (satisfaction with information/decision-making) and FS-ICU/total (overall satisfaction with the ICU). The essential predictors that influence family satisfaction were identified using quantitative and qualitative analyses. RESULTS: Seventy-three of the 227 patients' NOK who initially agreed completed the FS-ICU questionnaire (response rate 32.2%). The mean FS-ICU/total was 63.9 (standard deviation [SD], 30.8). The mean score for satisfaction with FS-ICU/dm was lower than the FS-ICU/care (62.1 [SD, 30.3) vs 65.4 (SD, 31.4); P < 0.001]. There was no difference in mean FS-ICU/total scores between survivors (n = 65; 89%) and non-survivors (n = 8, 11%). Higher patient Acute Physiology and Chronic Health Evaluation III score, female NOK and the patient dying in the ICU were independent predictors for FS-ICU/total score, while a telephone call at least once a day by an ICU doctor was related to family satisfaction for FS-ICU/dm. CONCLUSIONS: There was low overall family satisfaction with ICU care and virtual communication strategies adopted during the COVID-19 pandemic. Efforts should be targeted for improving factors with virtual communication that cause low family satisfaction during the COVID-19 pandemic.

Implementation of genomic surveillance of SARS-CoV-2 in the Caribbean: Lessons learned for sustainability in resource-limited settings

The COVID-19 pandemic highlighted the importance of global genomic surveillance to monitor the emergence and spread of SARS-CoV-2 variants and inform public health decision-making. Until December 2020 there was minimal capacity for viral genomic surveillance in most Caribbean countries. To overcome this constraint, the COVID-19: Infectious disease Molecular epidemiology for PAthogen Control & Tracking (COVID-19 IMPACT) project was implemented to establish rapid SARS-CoV-2 whole genome nanopore sequencing at The University of the West Indies (UWI) in Trinidad and Tobago (T&T) and provide needed SARS-CoV-2 sequencing services for T&T and other Caribbean Public Health Agency Member States (CMS). Using the Oxford Nanopore Technologies MinION sequencing platform and ARTIC network sequencing protocols and bioinformatics pipeline, a total of 3610 SARS-CoV-2 positive RNA samples, received from 17 CMS, were sequenced in-situ during the period December 5th 2020 to December 31st 2021. Ninety-one Pango lineages, including those of five variants of concern (VOC), were identified. Genetic analysis revealed at least 260 introductions to the CMS from other global regions. For each of the 17 CMS, the percentage of reported COVID-19 cases sequenced by the COVID-19 IMPACT laboratory ranged from 0·02% to 3·80% (median = 1·12%). Sequences submitted to GISAID by our study represented 73·3% of all SARS-CoV-2 sequences from the 17 CMS available on the database up to December 31st 2021. Increased staffing, process and infrastructural improvement over the course of the project helped reduce turnaround times for reporting to originating institutions and sequence uploads to GISAID. Insights from our genomic surveillance network in the Caribbean region directly influenced non-pharmaceutical countermeasures in the CMS countries. However, limited availability of associated surveillance and clinical data made it challenging to contextualise the observed SARS-CoV-2 diversity and evolution, highlighting the need for development of infrastructure for collecting and integrating genomic sequencing data and sample-associated metadata.

Using Non-Invasive Respiratory Monitoring for COVID-19 Pulmonary Embolism Diagnosis.

With the high incidence rate of pulmonary embolism (PE) and pneumonia reported in hospitalized patients with COVID-19, the ability to determine the dominant etiology for severe respiratory distress quickly and accurately is crucial to a patient's well-being. Traditionally, D-dimer blood tests and diagnostic imaging studies would be utilized to determine the presence of a PE or a venous thromboembolism. However, COVID-19 places patients in a prothrombotic state and performing diagnostic imaging studies on all patients with COVID-19 would be impractical, making the need for a simple and reliable method to determine the likelihood of PE or venous thromboembolism a priority for emergency departments. The authors believe the use of non-invasive respiratory monitoring technology to assess lung function in hospitalized patients with COVID-19 can aid in discerning the dominant hypoxia etiology and tailoring of their treatment. Here, the authors outline a case and method of using non-invasive respiratory monitoring of lung function in the successful diagnosis of a PE in a 62-year-old patient with COVID-19.

Salmonella-mediated oral delivery of multiple-target vaccine constructs with conserved and variable regions of SARS-CoV-2 protect against the Delta and Omicron variants in hamster.

Since the emergence of the pandemic COVID19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the development of vaccines has been the prime strategy to control the disease transmission. Most of the developed vaccines target the spike protein, however, the emerging variants have alterations, particularly at the same region which may pose resistance to neutralizing antibodies. In this study, we explored the variable and conserved regions of SARS-CoV-2 as a potential inclusion in a multiple-target vaccine with the exploitation of Salmonella-based vector for oral mRNA vaccine against Delta and Omicron variants. Increased IgG and IgA levels imply the induction of humoral response and the CD4+, CD8+ and IFN-γ+ sub-population level exhibits cell-mediated immune responses. The degree of CD44+ cells indicates the induction of memory cells corresponding to long-term immune responses. Furthermore, we assessed the protective efficacy of the vaccines against the Delta and Omicron variants in the hamster model. The vaccine constructs induced neutralizing antibodies and protected the viral-challenged hamsters with significant decrease in lung viral load and reduced histopathological lesions. These results reinforce the use of the conserved and variable regions as potential antigen targets of SARS-CoV-2 as well as the exploitation of bacteria-mediated delivery for oral mRNA vaccine development.

Virtual nature experiences and mindfulness practices while working from home during COVID-19: Effects on stress, focus, and creativity.

In this study, we focus on the impact of daily virtual nature experiences combined with mindfulness practices on remote workers' creativity, stress, and focus over an extended period (9 weeks) during the COVID-19 pandemic. Our results show a positive effect of virtual reality (VR) nature experience on increasing focus and reducing stress. When VR nature and mindfulness practices were combined, we also found an increase in convergent thinking task performance. Our findings demonstrate that 10-minute daily exposure to VR nature and mindfulness practices could compensate for some of the adverse effects of working remotely by improving some aspects of workers' well-being and creativity.

Pivoting to online: The benefits, challenges and possibilities for international programme evaluations

Global South non-government organizations rely on international funding and aid for continued service delivery. Service evaluation plays a significant role in ensuring compliance and ongoing service funding. Traditional service evaluation approaches could not take place during 2021 due to COVID-19, alternate mechanisms needed to be embraced. This article reports on the benefits and challenges of undertaking service evaluations online during the pandemic and the learnings and possibilities for a post-pandemic world. It emphasizes the importance of translating a relational approach to service evaluation to the online environment. Key learnings include that while some of the benefits of context and in-person connection are lost, taking a relational approach involving careful planning and reflexivity means the online evaluation process can be successful. Undertaking service evaluations online offers possibilities in a post-pandemic world as cost-effective alternatives to the expensive and time-consuming reality of in-person service evaluation across international borders and within development contexts. [ FROM AUTHOR]

SARS-CoV-2 drives NLRP3 inflammasome activation in human microglia through spike protein.

Coronavirus disease-2019 (COVID-19) is primarily a respiratory disease, however, an increasing number of reports indicate that SARS-CoV-2 infection can also cause severe neurological manifestations, including precipitating cases of probable Parkinson's disease. As microglial NLRP3 inflammasome activation is a major driver of neurodegeneration, here we interrogated whether SARS-CoV-2 can promote microglial NLRP3 inflammasome activation. Using SARS-CoV-2 infection of transgenic mice expressing human angiotensin-converting enzyme 2 (hACE2) as a COVID-19 pre-clinical model, we established the presence of virus in the brain together with microglial activation and NLRP3 inflammasome upregulation in comparison to uninfected mice. Next, utilising a model of human monocyte-derived microglia, we identified that SARS-CoV-2 isolates can bind and enter human microglia in the absence of viral replication. This interaction of virus and microglia directly induced robust inflammasome activation, even in the absence of another priming signal. Mechanistically, we demonstrated that purified SARS-CoV-2 spike glycoprotein activated the NLRP3 inflammasome in LPS-primed microglia, in a ACE2-dependent manner. Spike protein also could prime the inflammasome in microglia through NF-κB signalling, allowing for activation through either ATP, nigericin or α-synuclein. Notably, SARS-CoV-2 and spike protein-mediated microglial inflammasome activation was significantly enhanced in the presence of α-synuclein fibrils and was entirely ablated by NLRP3-inhibition. Finally, we demonstrate SARS-CoV-2 infected hACE2 mice treated orally post-infection with the NLRP3 inhibitory drug MCC950, have significantly reduced microglial inflammasome activation, and increased survival in comparison with untreated SARS-CoV-2 infected mice. These results support a possible mechanism of microglial innate immune activation by SARS-CoV-2, which could explain the increased vulnerability to developing neurological symptoms akin to Parkinson's disease in COVID-19 infected individuals, and a potential therapeutic avenue for intervention.

The Evolution of Medical Countermeasures for Ebola Virus Disease: Lessons Learned and Next Steps.

The Ebola virus disease outbreak that occurred in Western Africa from 2013-2016, and subsequent smaller but increasingly frequent outbreaks of Ebola virus disease in recent years, spurred an unprecedented effort to develop and deploy effective vaccines, therapeutics, and diagnostics. This effort led to the U.S. regulatory approval of a diagnostic test, two vaccines, and two therapeutics for Ebola virus disease indications. Moreover, the establishment of fieldable diagnostic tests improved the speed with which patients can be diagnosed and public health resources mobilized. The United States government has played and continues to play a key role in funding and coordinating these medical countermeasure efforts. Here, we describe the coordinated U.S. government response to develop medical countermeasures for Ebola virus disease and we identify lessons learned that may improve future efforts to develop and deploy effective countermeasures against other filoviruses, such as Sudan virus and Marburg virus.

SARS‐CoV‐2 triggers complement activation through interactions with heparan sulfate

Objectives To determine whether SARS‐CoV‐2 can trigger complement activation, the pathways that are involved and the functional significance of the resultant effect. Methods SARS‐CoV‐2 was inoculated into a human lepirudin‐anticoagulated whole blood model, which contains a full repertoire of complement factors and leukocytes that express complement receptors. Complement activation was determined by measuring C5a production with an ELISA, and pretreatment with specific inhibitors was used to identify the pathways involved. The functional significance of this was then assessed by measuring markers of C5a signalling including leukocyte C5aR1 internalisation and CD11b upregulation with flow cytometry. Results SARS‐CoV‐2 inoculation in this whole blood model caused progressive C5a production over 24 h, which was significantly reduced by inhibitors for factor B, C3, C5 and heparan sulfate. However, this phenomenon could not be replicated in cell‐free plasma, highlighting the requirement for cell surface interactions with heparan sulfate. Functional analysis of this phenomenon revealed that C5aR1 signalling and CD11b upregulation in granulocytes and monocytes was delayed and only occurred after 24 h. Conclusion SARS‐CoV‐2 is a noncanonical alternative pathway activator that progressively triggers complement activation through interactions with heparan sulfate. The mechanisms by which SARS‐CoV‐2 activates complement remain unclear, and so here, we utilised an ex vivo human whole blood model to interrogate the pathways and functional responses involved. SARS‐CoV‐2 inoculation in blood caused progressive C5a production over 24 h, which was blocked entirely by inhibitors for factor B, C3, C5 and heparan sulfate. This study therefore provides direct mechanistic evidence for SARS‐CoV‐2 driving complement activation and the requirement for cell surfaces and heparan sulfate.

Association of Frailty, Age, and Biological Sex With Severe Acute Respiratory Syndrome Coronavirus 2 Messenger RNA Vaccine-Induced Immunity in Older Adults.

BACKGROUND: Male sex and old age are risk factors for severe coronavirus disease 2019, but the intersection of sex and aging on antibody responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines has not been characterized. METHODS: Plasma samples were collected from older adults (aged 75-98 years) before and after 3 doses of SARS-CoV-2 mRNA vaccination, and from younger adults (aged 18-74 years) post-dose 2, for comparison. Antibody binding to SARS-CoV-2 antigens (spike protein [S], S receptor-binding domain, and nucleocapsid), functional activity against S, and live-virus neutralization were measured against the vaccine virus and the Alpha, Delta, and Omicron variants of concern (VOCs). RESULTS: Vaccination induced greater antibody titers in older females than in older males, with both age and frailty associated with reduced antibody responses in males but not females. Responses declined significantly in the 6 months after the second dose. The third dose restored functional antibody responses and eliminated disparities caused by sex, age, and frailty in older adults. Responses to the VOCs, particularly the Omicron variant, were significantly reduced relative to the vaccine virus, with older males having lower titers to the VOCs than older females. Older adults had lower responses to the vaccine and VOC viruses than younger adults, with greater disparities in males than in females. CONCLUSIONS: Older and frail males may be more vulnerable to breakthrough infections owing to low antibody responses before receipt of a third vaccine dose. Promoting third dose coverage in older adults, especially males, is crucial to protecting this vulnerable population.

A metagenomic DNA sequencing assay that is robust against environmental DNA contamination.

Metagenomic DNA sequencing is a powerful tool to characterize microbial communities but is sensitive to environmental DNA contamination, in particular when applied to samples with low microbial biomass. Here, we present Sample-Intrinsic microbial DNA Found by Tagging and sequencing (SIFT-seq) a metagenomic sequencing assay that is robust against environmental DNA contamination introduced during sample preparation. The core idea of SIFT-seq is to tag the DNA in the sample prior to DNA isolation and library preparation with a label that can be recorded by DNA sequencing. Any contaminating DNA that is introduced in the sample after tagging can then be bioinformatically identified and removed. We applied SIFT-seq to screen for infections from microorganisms with low burden in blood and urine, to identify COVID-19 co-infection, to characterize the urinary microbiome, and to identify microbial DNA signatures of sepsis and inflammatory bowel disease in blood.

Oral mRNA Vaccines Against Infectious Diseases- A Bacterial Perspective [Invited].

The mRNA vaccines from Pfizer/BioNTech and Moderna were granted emergency approval in record time in the history of vaccinology and played an instrumental role in limiting the pandemic caused by SARS-CoV-2. The success of these vaccines resulted from over 3 decades of research from many scientists. However, the development of orally administrable mRNA vaccine development is surprisingly underexplored. Our group specializing in Salmonella-based vaccines explored the possibility of oral mRNA vaccine development. Oral delivery was made possible by the exploitation of the Semliki Forest viral replicon and Salmonella vehicle for transgene amplification and gene delivery, respectively. Herein we highlight the prospect of developing oral replicon-based mRNA vaccines against infectious diseases based on our recent primary studies on SARS-CoV-2. Further, we discuss the potential advantages and limitations of bacterial gene delivery.

A Simplified SARS-CoV-2 Mouse Model Demonstrates Protection by an Oral Replicon-Based mRNA Vaccine.

A mouse model of SARS-CoV-2 that can be developed in any molecular biology lab with standard facilities will be valuable in evaluating drugs and vaccines. Here we present a simplified SARS-CoV-2 mouse model exploiting the rapid adenoviral purification method. Mice that are sensitive to SARS-CoV-2 infection were generated by transducing human angiotensin-converting enzyme 2 (hACE2) by an adenovirus. The expression kinetics of the hACE2 in transduced mice were assessed by immunohistochemistry, RT-PCR, and qPCR. Further, the ability of the hACE2 to support viral replication was determined in vitro and in vivo. The hACE2 expression in the lungs of mice was observed for at least nine days after transduction. The murine macrophages expressing hACE2 supported viral replication with detection of high viral titers. Next, in vivo studies were carried out to determine viral replication and lung disease following SARS-CoV-2 challenge. The model supported viral replication, and the challenged mouse developed lung disease characteristic of moderate interstitial pneumonia. Further, we illustrated the utility of the system by demonstrating protection using an oral mRNA vaccine. The multicistronic vaccine design enabled by the viral self-cleaving peptides targets receptor binding domain (RBD), heptad repeat domain (HR), membrane glycoprotein (M) and epitopes of nsp13 of parental SARS-CoV-2. Further, Salmonella and Semliki Forest virus replicon were exploited, respectively, for gene delivery and mRNA expression. We recorded potent cross-protective neutralizing antibodies in immunized mice against the SARS-CoV-2 delta variant. The vaccine protected the mice against viral replication and SARS-CoV-2-induced weight loss and lung pathology. The findings support the suitability of the model for preclinical evaluation of anti-SARS-CoV-2 therapies and vaccines. In addition, the findings provide novel insights into mRNA vaccine design against infectious diseases not limiting to SARS-CoV-2.