SARS-CoV-2: phylogenetic origins, pathogenesis, modes of transmission, and the potential role of nanotechnology

[SARS-CoV-2 Infection in Pregnancy and Incidence of Congenital Malformations - is there a Correlation? Analysis of 8032 Pregnancies from the CRONOS Registry]

BACKGROUND

Based on single case reports, the COVID-19 Related Obstetric and Neonatal Outcome Study (CRONOS) registry, sponsored by the German Society for Perinatal Medicine (DGPM), investigated the likelihood that SARS-CoV-2 infections of the mother in (early) pregnancy cause embryopathies and/or fetopathies.

MATERIAL/METHODS

The CRONOS registry enrolled a total of 8032 women with confirmed SARS-CoV-2 infection during pregnancy at more than 130 participating hospitals from April 2020 to February 2023. Both maternal and fetal data were documented and the anonymized multicenter data were analyzed.

RESULTS

Of 7142 fully documented pregnancies (including postnatal data), 140 showed congenital malformations. 8.57% of the mothers had had a SARS-CoV-2-infection in the 1st trimester and 36.43% in the 2nd trimester. In 66 cases with congenital malformations (47.14%), the malformation was only detected after the diagnosis of a maternal SARS-CoV-2 infection. The overall prevalence of congenital malformations in this cohort was 1.96%, compared to a prevalence of 2.39% reported in the EUROCAT (European network of population-based registries for the epidemiological surveillance of congenital anomalies) pre-pandemic registry between 2017-2019.

DISCUSSION

Our multicenter data argue against a link between maternal SARS-CoV-2 infection in early pregnancy and congenital malformation.

Spotlight on therapeutic efficiency of green synthesis metals and their oxide nanoparticles in periodontitis

Periodontitis, one of the most prevalent dental diseases, causes the loss of bone and gum tissue that hold teeth in place. Several bacteria, commonly present in clinically healthy oral cavities, may induce and perpetuate periodontitis when their concentration rises in the gingival sulcus. Antibacterial effect against various Gram-negative and Gram-positive bacteria, including pathogenic and drug-resistant ones, has been shown for several distinct transient metal and metal oxide NPs. Therefore, NPs may be used in biomedicine to treat periodontal problems and in nanotechnology to inhibit the development of microorganisms. Instead of using harmful chemicals or energy-intensive machinery, biosynthesis of metal and metal oxide nanoparticles (NPs) has been suggested. To produce metal and metal oxide NPs, the ideal technique is "Green" synthesis because of its low toxicity and safety for human health and the environment. Gold NPs (AuNPs) appear to be less toxic to mammalian cells than other nanometals because their antibacterial activity is not dependent on reactive oxygen species (ROS). AgNPs also possess chemical stability, catalytic activity, and superior electrical and thermal conductivity, to name a few of their other advantageous characteristics. It was observed that zinc oxide (ZnO) NPs and copper (Cu) NPs exhibited discernible inhibitory effects against gram-positive and gram-negative bacterial strains, respectively. ZnO NPs demonstrated bactericidal activity against the microorganisms responsible for periodontitis. Medications containing magnetic NPs are highly effective against multidrug-resistant bacterial and fungal infections. The titanium dioxide (TiO2) NPs are implicated in elevating salivary peroxidase activity in individuals diagnosed with chronic periodontitis. Furthermore, specific metallic NPs have the potential to enhance the antimicrobial efficacy of periodontitis treatments when combined. Therefore, these NPs, as well as their oxide NPs, are only some of the metals and metal oxides that have been synthesized in environmentally friendly ways and shown to have therapeutic benefits against periodontitis.

SARS-CoV-2 in Pregnancy, Birth and Puerperium. Guideline of the DGGG und DGPM (S2k-Level, AWMF Registry Number 015/092, March 2022)

Objective This S2k guideline of the German Society for Gynecology and Obstetrics (DGGG) and the German Society of Perinatal Medicine (DGPM) contains consensus-based recommendations for the care and treatment of pregnant women, parturient women, women who have recently given birth, and breastfeeding women with SARS-CoV-2 infection and their newborn infants. The aim of the guideline is to provide recommendations for action in the time of the COVID-19 pandemic for professionals caring for the above-listed groups of people.

Methods The PICO format was used to develop specific questions. A systematic targeted search of the literature was carried out using PubMed, and previously formulated statements and recommendations issued by the DGGG and the DGPM were used to summarize the evidence. This guideline also drew on research data from the CRONOS registry. As the data basis was insufficient for a purely evidence-based guideline, the guideline was compiled using an S2k-level consensus-based process. After summarizing and presenting the available data, the guideline authors drafted recommendations in response to the formulated PICO questions, which were then discussed and voted on.

Recommendations Recommendations on hygiene measures, prevention measures and care during pregnancy, delivery, the puerperium and while breastfeeding were prepared. They also included aspects relating to the monitoring of mother and child during and after infection with COVID-19, indications for thrombosis prophylaxis, caring for women with COVID-19 while they are giving birth, the presence of birth companions, postnatal care, and testing and monitoring the neonate during rooming-in or on the pediatric ward.

Application of nanomaterials against SARS-CoV-2: An emphasis on their usefulness against emerging variants of concern

Researchers are now looking to nanomaterials to fight serious infectious diseases that cause outbreaks and even pandemics. SARS-CoV-2 brought chaos to almost every walk of life in the past 2 years and has challenged every available treatment method. Although vaccines were developed in no time against it, the most pressing issue was the emergence of variants of concern arising because of the rapidly evolving viral strains. The higher pathogenicity and, in turn, the higher mortality rate of infections caused by these variants renders the existing vaccines less effective and the effort to produce further vaccines a costly endeavor. While several techniques, such as immunotherapy and repurposed pharmaceutical research, are being studied to minimize viral infection, the fundamentals of nanotechnology must also be considered to enhance the anti-SARS-CoV-2 efforts. For instance, silver nanoparticles (AgNPs) have been applied against SARS-CoV-2 effectively. Similarly, nanomaterials have been tested in masks, gloves, and disinfectants to aid in controlling SARS-CoV-2. Nanotechnology has also contributed to diagnoses such as rapid and accurate detection and treatment such as the delivery of mRNA vaccines and other antiviral agents into the body. The development of polymeric nanoparticles has been dubbed a strategy of choice over traditional drugs because of their tunable release kinetics, specificity, and multimodal drug composition. Our article explores the potential of nanomaterials in managing the variants of concern. This will be achieved by highlighting the inherent ability of nanomaterials to act against the virus on fronts such as inhibition of SARS-CoV-2 entry, inhibition of RNA replication in SARS-CoV-2, and finally, inhibition of their release. In this review, a detailed discussion on the potential of nanomaterials in these areas will be tallied with their potential against the current and emerging future variants of concern.

Potential Predictive Value of miR-125b-5p, miR-155-5p and Their Target Genes in the Course of COVID-19

Purpose

This study aimed to provide new biomarkers for predicting the disease course of COVID-19 by analyzing the dynamic changes of microRNA (miRNA) and its target gene expression in the serum of COVID-19 patients at different stages.

Methods

Serum samples were collected from all COVID-19 patients at three time points: the acute stage, the turn-negative stage, and the recovery stage. The expression level of miRNA and the target mRNA was measured by Quantitative Real-Time Polymerase Chain Reaction (RT-qPCR). The classification tree model was established to predict the disease course, and the prediction efficiency of independent variables in the model was analyzed using the receiver operating characteristic (ROC) curve.

Results

The expression of miR-125b-5p and miR-155-5p was significantly up-regulated in the acute stage and gradually decreased in the turn-negative and recovery stages. The expression of the target genes CDH5, STAT3, and TRIM32 gradually down-regulated in the acute, turn-negative, and recovery stages. MiR-125b-5p, miR-155-5p, STAT3, and TRIM32 constituted a classification tree model with 100% accuracy of prediction and AUC >0.7 for identification and prediction in all stages.

Conclusion

MiR-125b-5p, miR-155-5p, STAT3, and TRIM32 could be useful biomarkers to predict the time nodes of the acute, turn-negative, and recovery stages of COVID-19.

An insight to the therapeutic potential of algae-derived sulfated polysaccharides and polyunsaturated fatty acids: Focusing on the COVID-19

Covid-19 pandemic severely affected human health worldwide. The rapidly increasing COVID-19 cases and successive mutations of the virus have made it a major challenge for scientists to find the best and efficient drug/vaccine/strategy to counteract the virus pathogenesis. As a result of research in scientific databases, regulating the immune system and its responses with nutrients and nutritional interventions is the most critical solution to prevent and combat this infection. Also, modulating other organs such as the intestine with these compounds can lead to the vaccines' effectiveness. Marine resources, mainly algae, are rich sources of nutrients and bioactive compounds with known immunomodulatory properties and the gut microbiome regulations. According to the purpose of the review, algae-derived bioactive compounds with immunomodulatory activities, sulfated polysaccharides, and polyunsaturated fatty acids have a good effect on the immune system. In addition, they have probiotic/prebiotic properties in the intestine and modulate the gut microbiomes; therefore, they can increase the effectiveness of vaccines produced. Thus, they with respectable safety, immune regulation, and modulation of microbiota have potential therapeutic against infections, especially COVID-19. They can also be employed as promising candidates for the prevention and treatment of viral infections, such as COVID-19.

Plasma Torquetenovirus (TTV) microRNAs and severity of COVID-19

Background

Torquetenovirus (TTV), a widespread anellovirus recognized as the main component of the healthy human virome, displays viremia that is highly susceptible to variations in immune competence. TTV possesses microRNA (miRNA)-coding sequences that might be involved in viral immune evasion. Among TTV-encoded miRNAs, miRNA t1a, t3b, and tth8 have been found in biological fluids. Here, the presence of TTV DNA and TTV miRNAs in the plasma of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected subjects was investigated to monitor the possible association with coronavirus disease 2019 (COVID-19) severity.

Methods

Detection of TTV DNA and miRNA t1a, t3b, and tth8 was investigated in plasma samples of 56 SARS-CoV-2-infected subjects with a spectrum of different COVID-19 outcomes. TTV DNA and TTV miRNAs were assessed with a universal single step real-time TaqMan PCR assay and miRNA quantitative RT-PCR miRNA assay, respectively.

Results

The TTV DNA prevalence was 59%, whereas at least one TTV miRNA was found in 94% of the patients tested. miRNA tth8 was detected in 91% of subjects, followed by miRNAs t3b (64%) and miRNAt1a (30%). Remarkably, although TTV DNA was unrelated to COVID-19 severity, miRNA tth8 was significantly associated with the degree of disease (adjusted incidence rate ratio (IRR) 2.04, 95% CI 1.14–3.63, for the subjects in the high severity group compared to those in the low severity group).

Conclusions

Our findings encourage further investigation to understand the potential role of TTV miRNAs in the different outcomes of COVID-19 at early and late stages.

Changes in cognitive functioning after COVID-19: A systematic review and meta-analysis

Introduction

We conducted a systematic review and meta‐analysis of the cognitive effects of coronavirus disease 2019 (COVID‐19) in adults with no prior history of cognitive impairment.

Methods

Searches in Medline/Web of Science/Embase from January 1, 2020, to December 13, 2021, were performed following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines.  A meta‐analysis of the Montreal Cognitive Assessment (MoCA) total score comparing recovered COVID‐19 and healthy controls was performed.

Results

Oof 6202 articles, 27 studies with 2049 individuals were included (mean age = 56.05 years, evaluation time ranged from the acute phase to 7 months post‐infection). Impairment in executive functions, attention, and memory were found in post‐COVID‐19 patients.  The meta‐analysis was performed with a subgroup of 290 individuals and showed a difference in MoCA score between post‐COVID‐19 patients versus controls (mean difference = −0.94, 95% confidence interval [CI] −1.59, −0.29; P = .0049).

Discussion

Patients recovered from COVID‐19 have lower general cognition compared to healthy controls up to 7 months post‐infection.

Mapping the distributions of blood-sucking mites and mite-borne agents in China: a modeling study

Background

Emerging mite-borne pathogens and associated disease burdens in recent decades are raising serious public health concerns, yet their distributions and ecology remain under-investigated. We aim to describe the geographical distributions of blood-sucking mites and mite-borne agents and to assess their ecological niches in China.

Methods

We mapped 549 species of blood-sucking mites belonging to 100 genera at the county level and eight mite-associated agents detected from 36 species of blood-sucking mites in China during 1978–2020. Impacts of climatic and environmental factors on the ecology of 21 predominant vector mites and a leading pathogen, Orientia tsutsugamushi, were assessed using boosted regression tree (BRT) models, and model-predicted risks were mapped. We also estimated the model-predicted number, area and population size of affected counties for each of the 21 mite species in China.

Results

Laelaps echidninus is the leading mite species that potentially affects 744 million people, followed by La. jettmari (517 million) and Eulaelaps stabularis (452 million). Leptotrombidium scutellare is the mite species harboring the highest variety of mite-borne agents including four Rickettsia species and two viruses, followed by Eu. stabularis (2 agents), L. palpale (2) and La. echidninus (2). The top two agents that parasitize the largest number of mite species are O. tsutsugamushi (28 species) and hantavirus (8). Mammalian richness, annual mean temperature and precipitation of the driest quarter jointly determine the ecology of the mites, forming four clusters of major mite species with distinct geographic distributions. High-risk areas of O. tsutsugamushi are mainly distributed in southern and eastern coastal provinces where 71.5 million people live.

Conclusions

Ecological niches of major mite species and mite-borne pathogens are much more extensive than what have been observed, necessitating expansion of current filed surveillance.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-022-00966-0.

Identification of host transcriptome-guided repurposable drugs for SARS-CoV-1 infections and their validation with SARS-CoV-2 infections by using the integrated bioinformatics approaches

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is one of the most severe global pandemic due to its high pathogenicity and death rate starting from the end of 2019. Though there are some vaccines available against SAER-CoV-2 infections, we are worried about their effectiveness, due to its unstable sequence patterns. Therefore, beside vaccines, globally effective supporting drugs are also required for the treatment against SARS-CoV-2 infection. To explore commonly effective repurposable drugs for the treatment against different variants of coronavirus infections, in this article, an attempt was made to explore host genomic biomarkers guided repurposable drugs for SARS-CoV-1 infections and their validation with SARS-CoV-2 infections by using the integrated bioinformatics approaches. At first, we identified 138 differentially expressed genes (DEGs) between SARS-CoV-1 infected and control samples by analyzing high throughput gene-expression profiles to select drug target key receptors. Then we identified top-ranked 11 key DEGs (SMAD4, GSK3B, SIRT1, ATM, RIPK1, PRKACB, MED17, CCT2, BIRC3, ETS1 and TXN) as hub genes (HubGs) by protein-protein interaction (PPI) network analysis of DEGs highlighting their functions, pathways, regulators and linkage with other disease risks that may influence SARS-CoV-1 infections. The DEGs-set enrichment analysis significantly detected some crucial biological processes (immune response, regulation of angiogenesis, apoptotic process, cytokine production and programmed cell death, response to hypoxia and oxidative stress), molecular functions (transcription factor binding and oxidoreductase activity) and pathways (transcriptional mis-regulation in cancer, pathways in cancer, chemokine signaling pathway) that are associated with SARS-CoV-1 infections as well as SARS-CoV-2 infections by involving HubGs. The gene regulatory network (GRN) analysis detected some transcription factors (FOXC1, GATA2, YY1, FOXL1, TP53 and SRF) and micro-RNAs (hsa-mir-92a-3p, hsa-mir-155-5p, hsa-mir-106b-5p, hsa-mir-34a-5p and hsa-mir-19b-3p) as the key transcriptional and post- transcriptional regulators of HubGs, respectively. We also detected some chemicals (Valproic Acid, Cyclosporine, Copper Sulfate and arsenic trioxide) that may regulates HubGs. The disease-HubGs interaction analysis showed that our predicted HubGs are also associated with several other diseases including different types of lung diseases. Then we considered 11 HubGs mediated proteins and their regulatory 6 key TFs proteins as the drug target proteins (receptors) and performed their docking analysis with the SARS-CoV-2 3CL protease-guided top listed 90 anti-viral drugs out of 3410. We found Rapamycin, Tacrolimus, Torin-2, Radotinib, Danoprevir, Ivermectin and Daclatasvir as the top-ranked 7 candidate-drugs with respect to our proposed target proteins for the treatment against SARS-CoV-1 infections. Then, we validated these 7 candidate-drugs against the already published top-ranked 11 target proteins associated with SARS-CoV-2 infections by molecular docking simulation and found their significant binding affinity scores with our proposed candidate-drugs. Finally, we validated all of our findings by the literature review. Therefore, the proposed candidate-drugs might play a vital role for the treatment against different variants of SARS-CoV-2 infections with comorbidities, since the proposed HubGs are also associated with several comorbidities.

Profiles in conspiracism: Associations with two psychiatric syndromes, religiosity and pandemic-related health behaviors

INTRODUCTION

Conspiratorial beliefs are often maladaptive for individuals and dangerous for societies. Other prevalent belief systems such as (normative) religious belief and (pathological) delusional belief show parallels to conspiratorial beliefs, which may also be linked to excessive social media exposure. We conducted an online survey to characterize heterogeneous profiles of conspiracy-mindedness, with respect to these other phenomena.

METHODS

Eight hundred and thirty six American adults from online panels completed validated questionnaires including the Conspiracy Mindedness Questionnaire (CMQ), Centrality of Religion Scale (CRS), Peters Delusion Inventory (PDI; 21-item version), and Facebook Addiction Scale (FAS). Additionally, they completed 4 questions addressing categorical belief in the origin of SARS-CoV-2, and pandemic-related health behaviors. Total scores on each questionnaire were Z-transformed and entered into K-means cluster analysis. Cluster membership was used in post-hoc analyses to compare pandemic-related items.

RESULTS

An optimal solution included 3 clusters with above-mean (high) CMQ and 3 below-mean (low) CMQ scores. The 3 high-CMQ clusters included: (1) high-religion, low-social media addiction; (2) high religion, social media addiction and delusion; (3) low religion and delusion. High-CMQ clusters 1 and 2 each had rates of zoonotic and malevolent viral origin beliefs that were relatively lower and higher than the grand sample rates, respectively. Significant differences in intended pandemic health-related behaviors among the high-CMQ clusters (compared to the rest of the sample) included Cluster 1-high on Precautions and low on Vaccination; Cluster 2-high on Testing. Respondents who endorsed SARS-CoV-2 origin beliefs (across clusters) that were least plausible and most malevolent were least inclined to engage in pandemic health behaviors.

CONCLUSIONS

Distinct subpopulations of persons with high conspiracy-mindedness exist, which are highly heterogeneous in their other coexisting beliefs and behaviors. Some of these may be pathological, such as delusional belief and social media addiction-like behavior, and they have varied associations with pandemic-related belief and behavior. These results, while cross-sectional, suggest that the psychological origins and consequences of conspiratorial beliefs may not be unitary. Instead, conspiratorial belief may be a common expression of diverse psychological and social/experiential factors, and in turn exert varied influence on decisions and overt behavior.

Inhibition Ability of Natural Compounds on Receptor-Binding Domain of SARS-CoV2: An In Silico Approach

The lack of medication to treat COVID-19 is still an obstacle that needs to be addressed by all possible scientific approaches. It is essential to design newer drugs with varied approaches. A receptor-binding domain (RBD) is a key part of SARS-CoV-2 virus, located on its surface, that allows it to dock to ACE2 receptors present on human cells, which is followed by admission of virus into cells, and thus infection is triggered. Specific receptor-binding domains on the spike protein play a pivotal role in binding to the receptor. In this regard, the in silico method plays an important role, as it is more rapid and cost effective than the trial and error methods using experimental studies. A combination of virtual screening, molecular docking, molecular simulations and machine learning techniques are applied on a library of natural compounds to identify ligands that show significant binding affinity at the hydrophobic pocket of the RBD. A list of ligands with high binding affinity was obtained using molecular docking and molecular dynamics (MD) simulations for protein–ligand complexes. Machine learning (ML) classification schemes have been applied to obtain features of ligands and important descriptors, which help in identification of better binding ligands. A plethora of descriptors were used for training the self-organizing map algorithm. The model brings out descriptors important for protein–ligand interactions.

Aging and diabetes drive the COVID-19 forwards; unveiling nature and existing therapies for the treatment

Human SARS Coronavirus-2 (SARS-CoV-2) has infected more than 170 million people worldwide and resulted in more than 3.5 million deaths so far. The infection causes Coronavirus disease (COVID-19) in people of all age groups, notably diabetic and old age people, at a higher risk of infectivity and fatality. Around 35% of the patients who have died of the disease were diabetic. The infection is associated with weakening immune response, chronic inflammation, and potential direct pancreatic impairment. There seems to be a three-way association of the SARS-CoV-2 infection with diabetes and aging. The COVID-19 infection causes metabolism complications, which may induce diabetes and accelerate aging in healthy individuals. How does diabetes elevate the likelihood of the infection is not clearly understood. we summarize mechanisms of accelerated aging in COVID-19 and diabetes, and the possible correlation of these three diseases. Various drug candidates under different stages of pre-clinical or clinical developments give us hope for the development of COVID-19 therapeutics, but there is no approved drug so far to treat this disease. Here, we explored the potential of anti-diabetic and anti-aging natural compounds for the COVID-19 treatment. We have also reviewed different therapeutic strategies with plant-based natural products that may be used to cure patients infected with SARS-CoV-2 and post-infection syndrome.

Hidden in Plain Sight: Natural Products of Commensal Microbiota as an Environmental Selection Pressure for the Rise of New Variants of SARS-CoV-2

Since the emergence of SARS-CoV-2, little attention has been paid to the interplay between the interaction of virus and commensal microbiota. Here, we used molecular docking and dynamics simulations to study the interaction of some of the known metabolites and natural products (NPs) produced by commensal microbiota with the receptor binding domain (RBD) of the spike glycoprotein of SARS-CoV-2. The results predict that NPs of commensal microbiota such as bile acids and non-ribosomal peptides (NRPs), of which some are siderophores, bind to the wild-type RBD and interfere with its binding to the ACE2 receptor. N501Y mutation, which is present in many of the emerging variants of the virus, abolishes the predicted binding pocket of bile acids and NRPs. Based on these findings, available experimental data showing that bile acids reduce the binding affinity of wild-type RBD to the ACE2 receptor, and the data suggesting that the respiratory tract microbiota affect viral infection we put forward the following proposal: mutations such as N501Y enable the RBD to bind to the ACE2 receptor more effectively in the presence of NPs produced by the respiratory tract bacteria thereby, increasing the infectivity rate of the virus. We hope our data stimulate future works to better understand the interactions of NPs produced by commensal microbiota with respiratory viruses like SARS-CoV-2.

Multi-Organ Histopathological Changes in a Mouse Hepatitis Virus Model of COVID-19

Infection with SARS-CoV-2, the virus responsible for the global COVID-19 pandemic, causes a respiratory illness that can severely impact other organ systems and is possibly precipitated by cytokine storm, septic shock, thrombosis, and oxidative stress. SARS-CoV-2 infected individuals may be asymptomatic or may experience mild, moderate, or severe symptoms with or without pneumonia. The mechanisms by which SARS-CoV-2 infects humans are largely unknown. Mouse hepatitis virus 1 (MHV-1)-induced infection was used as a highly relevant surrogate animal model for this study. We further characterized this animal model and compared it with SARS-CoV-2 infection in humans. MHV-1 inoculated mice displayed death as well as weight loss, as reported earlier. We showed that MHV-1-infected mice at days 7-8 exhibit severe lung inflammation, peribronchiolar interstitial infiltration, bronchiolar epithelial cell necrosis and intra-alveolar necrotic debris, alveolar exudation (surrounding alveolar walls have capillaries that are dilated and filled with red blood cells), mononuclear cell infiltration, hyaline membrane formation, the presence of hemosiderin-laden macrophages, and interstitial edema. When compared to uninfected mice, the infected mice showed severe liver vascular congestion, luminal thrombosis of portal and sinusoidal vessels, hepatocyte degeneration, cell necrosis, and hemorrhagic changes. Proximal and distal tubular necrosis, hemorrhage in interstitial tissue, and the vacuolation of renal tubules were observed. The heart showed severe interstitial edema, vascular congestion, and dilation, as well as red blood cell extravasation into the interstitium. Upon examination of the MHV-1 infected mice brain, we observed congested blood vessels, perivascular cavitation, cortical pericellular halos, vacuolation of neuropils, darkly stained nuclei, pyknotic nuclei, and associated vacuolation of the neuropil in the cortex, as well as acute eosinophilic necrosis and necrotic neurons with fragmented nuclei and vacuolation in the hippocampus. Our findings suggest that the widespread thrombotic events observed in the surrogate animal model for SARS-CoV-2 mimic the reported findings in SARS-CoV-2 infected humans, representing a highly relevant and safe animal model for the study of the pathophysiologic mechanisms of SARS-CoV-2 for potential therapeutic interventions.

Role of gastrointestinal system on transmission and pathogenesis of SARS-CoV-2

Coronavirus disease 2019 (COVID-19) continues to pose a significant threat to global health. Primary prevention remains as a major strategy against the pandemic. Current evidence proves that aerosol and droplet-based routes are the main means of transmission of COVID-19 but other ways should be sought in order to prevent possible collateral transmission. The gastrointestinal system may be one such route. Angiotensin converting enzyme 2 is the target entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that is abundantly expressed in the gastrointestinal tract. SARS-CoV-2 is able to infect human enterocytes similar to severe acute respiratory syndrome and Middle Eastern respiratory syndrome. Herein this review, we discuss the current knowledge regarding the role of gastrointestinal transmission in transmission and pathophysiology of COVID-19.

A theoretical strategy for acceleration of human immune response against SARS-CoV-2: a fusion protein harboring virus-binding and pre-exposed antigen domains

Coronavirus disease 2019 (COVID-19) is a respiratory disease that outbreaks since December 2019 and spread globally. Various methods have been used to treat SARS-CoV-2 that is generally based on the information obtained from the therapeutic approaches used for SARS-COV and MERS patients. In this article, we introduce a theoretical strategy in which a two-domain fusion protein presents the virus to the immune system. This fusion protein contains a viral-binding domain such as the ACE2 domain and a domain such as the hepatitis B antigen that has previously been exposed to the immune system. This two-domain fusion protein, could be called “virus-presenting fusion protein”, would attach to the virus spike protein via the ACE2 domain while the hepatitis B antigen would be bound by anti-hepatitis B antibodies facilitating the opsonization and presentation of the virus to the immune system. We believe that this virus-presenting fusion protein will accelerate the immune response to the SARS-CoV-2 virus.

Animal Transmission of SARS-CoV-2 and the Welfare of Animals during the COVID-19 Pandemic

The accelerated pace of research into Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) necessitates periodic summaries of current research. The present paper reviews virus susceptibilities in species with frequent human contact, and factors that are best predictors of virus susceptibility. Species reviewed were those in contact with humans through entertainment, pet, or agricultural trades, and for whom reports (either anecdotal or published) exist regarding the SARS-CoV-2 virus and/or the resulting disease state COVID-19. Available literature was searched using an artificial intelligence (AI)-assisted engine, as well as via common databases, such as Web of Science and Medline. The present review focuses on susceptibility and transmissibility of SARS-CoV-2, and polymorphisms in transmembrane protease serine 2 (TMPRSS2) and angiotensin-converting enzyme 2 (ACE2) that contribute to species differences. Dogs and pigs appear to have low susceptibility, while ferrets, mink, some hamster species, cats, and nonhuman primates (particularly Old World species) have high susceptibility. Precautions may therefore be warranted in interactions with such species, and more selectivity practiced when choosing appropriate species to serve as models for research.