Enteric involvement of severe acute respiratory syndrome-associated coronavirus infection

Management of patients with digestive diseases during the COVID-19 pandemic. Clinical Practice Guidelines by the Russian scientific medical society of internal medicine (RSMSIM) and the Gastroenterological Scientific Society of Russia (2nd edition)

The presented clinical practice guidelines of the Gastroenterological Scientific Society of Russia (GSSR), diagnostic, and therapeutic approaches for patients with digestive diseases during the COVID-19 pandemic. The guidelines were approved by the XXIII Congress of the GSSR and the 22nd International Slavonic-Baltic Scientifi c Forum “St. Petersburg - Gastro-2020 ON-LINE” (St. Petersburg, June 11, 2020). The presented clinical practice guidelines of the Russian Scientific Medical Society of Internal Medicine (RSMSIM) and the Gastroenterological Scientific Society of Russia (GSSR), diagnostic, and therapeutic approaches for patients with digestive diseases during the COVID-19 pandemic. The recommendations were approved at the XV National Congress of Internal Medicine, XXIII Congress of NOGR on the basis of the 1st edition, adopted at the 22nd International Slavic- Baltic Scientific Forum “St. Petersburg - Gastro-2020 ON-LINE”.

Harmful Effects of COVID-19 on Major Human Body Organs: A Review

The world experienced the outbreak of a new pandemic disease in 2019, known as coronavirus (CoV) disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome-CoV-2 (SARS-CoV-2). The respiratory system is the organ system most commonly affected by COVID-19; however, several other organ systems have been reported to be affected. The SARS-CoV-2 RNA found in infected stub samples can cause lung contagion by binding to the angiotensin-converting enzyme-2 (ACE-2) receptor of the alveolar epithelial cells. The gut microbiota (GM) promote immunity, indicating that the alignment of the microbiota and corresponding metabolic processes in COVID-19 can help to identify novel biomarkers and new therapeutic targets for this disease. The cause of kidney damage in COVID-19 patients is possibly multifactorial, involving a complex mechanism that involves complement dysregulation and thrombotic microangiopathy, as well as the occurrence of a “cytokine storm” syndrome, which are immune responses that are abandoned and dysfunctional with unfavorable prognosis in severe COVID-19 cases. Furthermore, COVID-19 involves a continuous proliferation and activation of macrophages and lymphocytes. SARS-CoV-2 can also bind to the ACE-2 receptor expressed in the cerebral capillary endothelial cells that can invade the blood-brain wall, to penetrate the brain parenchyma. However, in the ongoing pandemic, there has been a surge in studies on a wide range of topics, including causes of respiratory failure, asymptomatic patients, intensive care patients, and survivors. This review briefly describes the damaging effects of COVID-19 on vital human organs and the inhibitory function of the ACE-2 receptor on the GM, which causes gut dysbiosis, and thus, this review discusses topics that have an opportunity for further investigation.

Detection of SARS-COV-2 receptor ACE-2 mRNA in thyroid cells: a clue for COVID-19-related subacute thyroiditis

PURPOSE

SARS-COV-2 is a pathogenic agent belonging to the coronavirus family, responsible for the current global world pandemic. Angiotensin-converting enzyme 2 (ACE-2) is the receptor for cellular entry of SARS-CoV-2. ACE-2 is a type I transmembrane metallo-carboxypeptidase involved in the Renin-Angiotensin pathway. By analyzing two independent databases, ACE-2 was identified in several human tissues including the thyroid. Although some cases of COVID-19-related subacute thyroiditis were recently described, direct proof for the expression of the ACE-2 mRNA in thyroid cells is still lacking. Aim of the present study was to investigate by RT-PCR whether the mRNA encoding for ACE-2 is present in human thyroid cells.

METHODS

RT-PCR was performed on in vitro ex vivo study on thyroid tissue samples (15 patients undergoing thyroidectomy for benign thyroid nodules) and primary thyroid cell cultures.

RESULTS

The ACE-2 mRNA was detected in all surgical thyroid tissue samples (n = 15). Compared with two reporter genes (GAPDH: 0.052 ± 0.0026 Cycles^-1; β-actin: 0.044 ± 0.0025 Cycles^-1; ACE-2: 0.035 ± 0.0024 Cycles^-1), the mean level of transcript expression for ACE-2 mRNA was abundant. The expression of ACE-2 mRNA in follicular cells was confirmed by analyzing primary cultures of thyroid cells, which expressed the ACE-2 mRNA at levels similar to tissues.

CONCLUSIONS

The results of the present study demonstrate that the mRNA encoding for the ACE-2 receptor is expressed in thyroid follicular cells, making them a potential target for SARS-COV-2 entry. Future clinical studies in patients with COVID-19 will be required for increase our understanding of the thyroid repercussions of SARS-CoV-2 infection.

COVID-19-from mucosal immunology to IBD patients

Viral infections with SARS-CoV-2 can cause a multi-facetted disease, which is not only characterized by pneumonia and overwhelming systemic inflammatory immune responses, but which can also directly affect the digestive system and infect intestinal epithelial cells. Here, we review the current understanding of intestinal tropism of SARS-CoV-2 infection, its impact on mucosal function and immunology and summarize the effect of immune-suppression in patients with inflammatory bowel disease (IBD) on disease outcome of COVID-19 and discuss IBD-relevant implications for the clinical management of SARS-CoV-2 infected individuals.

Clinical features, comorbidities, complications and treatment options in severe and non-severe COVID-19 patients: A systemic review and meta-analysis

OBJECTIVES

The aim of this analysis was to assess the prevalence of clinical features, comorbidities, complications and treatment options in the patients with COVID-19 and compare incidence of these clinical data in severe and non-severe patients.

DESIGN

Systemic review and Meta-analysis.

METHODS

PubMed, Embase, Scopus and Web of Sciences databases were searched to identify relevant papers until 20 July 2020. All studies comparing clinical data of severe and non-severe patients of COVID-19 were included. Heterogeneity across included studies was determined using Cochrane's Q test and the I2 statistic. Results were expressed as odds ratio with accompanying 95% confidence intervals.

RESULTS

Twelve studies with 3,046 patients were included. The result showed the most prevalent clinical symptoms were fever 88.3%, cough 62.2%, fatigue 39.5% and dyspnoea 31.5%. Further meta-analysis showed incidence of fever, cough, fatigue and dyspnoea was higher in severe patients. The most prevalent comorbidities were hypertension 22.6%, diabetes 11.5%, cardiovascular disease 10.3% and cancer 2.5%. We found that compared with non-severe patients, the symptoms, existing comorbidities and complications are prevalent in severe COVID-19 patients. Future well-methodologically designed studies from other populations are strongly recommended.

Microscopic Observation of SARS-Like Particles in RT-qPCR SARS-CoV-2 Positive Sewage Samples

The ongoing outbreak of novel coronavirus pneumonia (COVID-19) caused by SARS-CoV-2 infection has spread rapidly worldwide. The major transmission routes of SARS-CoV-2 are recognised as inhalation of aerosol/droplets and person-to-person contact. However, some studies have demonstrated that live SARS-CoV-2 can be isolated from the faeces and urine of infected patients, which can then enter the wastewater system. The currently available evidence indicates that the viral RNA present in wastewater may become a potential source of epidemiological data. However, to investigate whether wastewater may present a risk to humans such as sewage workers, we investigated whether intact particles of SARS-CoV-2 were observable and whether it was possible to isolate the virus in wastewater. Using a correlative strategy of light microscopy and electron microscopy (CLEM), we demonstrated the presence of intact and degraded SARS-like particles in RT-qPCR SARS-CoV-2-positive sewage sample collected in the city of Marseille. However, the viral infectivity assessment of SARS-CoV-2 in the wastewater was inconclusive, due to the presence of other viruses known to be highly resistant in the environment such as enteroviruses, rhinoviruses, and adenoviruses. Although the survival and the infectious risk of SARS-CoV-2 in wastewater cannot be excluded from our study, additional work may be required to investigate the stability, viability, fate, and decay mechanisms of SARS-CoV-2 thoroughly in wastewater.

COVID-19 and the gastrointestinal tract: Source of infection or merely a target of the inflammatory process following SARS-CoV-2 infection?

Gastrointestinal (GI) symptoms have been described in a conspicuous percentage of coronavirus disease 2019 (COVID-19) patients. This clinical evidence is supported by the detection of viral RNA in stool, which also supports the hypothesis of a possible fecal-oral transmission route. The involvement of GI tract in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is corroborated by the theoretical assumption that angiotensin converting enzyme 2, which is a SARS-CoV-2 target receptor, is present along the GI tract. Studies have pointed out that gut dysbiosis may occur in COVID-19 patients, with a possible correlation with disease severity and with complications such as multisystem inflammatory syndrome in children. However, the question to be addressed is whether dysbiosis is a consequence or a contributing cause of SARS-CoV-2 infection. In such a scenario, pharmacological therapies aimed at decreasing GI permeability may be beneficial for COVID-19 patients. Considering the possibility of a fecal-oral transmission route, water and environmental sanitation play a crucial role for COVID-19 containment, especially in developing countries.

The gut microbiome: a missing link in understanding the gastrointestinal manifestations of COVID-19?

Coronavirus disease 2019 (COVID-19), which is caused by infection with SARS-CoV-2, presents with a broad constellation of both respiratory and nonrespiratory symptoms, although it is primarily considered a respiratory disease. Gastrointestinal symptoms-including nausea, abdominal pain, vomiting, and diarrhea-rank chief among these. When coupled with the presence of viral RNA in fecal samples, the presence of gastrointestinal symptoms raises relevant questions regarding whether SARS-CoV-2 can productively infect the upper or lower gastrointestinal tract. Despite the well-documented prevalence of gastrointestinal symptoms and the high rate of SARS-CoV-2 fecal RNA shedding, the biological, clinical, and epidemiological relevance of these findings is unclear. Furthermore, the isolation of replication-competent virus from fecal samples has not been reproducibly and rigorously demonstrated. Although SARS-CoV-2 shedding likely occurs in a high proportion of patients, gastrointestinal symptoms affect only a subset of individuals. Herein, we summarize what is known about gastrointestinal symptoms and fecal viral shedding in COVID-19, explore the role of the gut microbiome in other respiratory diseases, speculate on the role of the gut microbiota in COVID-19, and discuss potential future directions. Taking these concepts together, we propose that studying gut microbiota perturbations in COVID-19 will enhance our understanding of the symptomology and pathophysiology of this novel devastating disease.

Severe acute respiratory syndrome coronavirus 2 for physicians: Molecular characteristics and host immunity (Review)

Recently, severe acute respiratory syndrome (SARS) coronavirus (CoV) 2 (SARS‑CoV‑2)‑causing CoV disease 2019 (COVID‑19) emerged in China and has become a global pandemic. SARS‑CoV‑2 is a novel CoV originating from β‑CoVs. Major distinctions in the gene sequences between SARS‑CoV and SARS‑CoV‑2 include the spike gene, open reading frame (ORF) 3b and ORF 8. SARS‑CoV‑2 infection is initiated when the virus interacts with angiotensin‑converting enzyme 2 (ACE2) receptors on host cells. Through this mechanism, the virus infects the alveolar, esophageal epithelial, ileum, colon and other cells on which ACE2 is highly expressed, causing damage to target organs. To date, host innate immunity may be the only identified direct factor associated with viral replication. However, increased ACE2 expression may upregulate the viral load indirectly by increasing the baseline level of infectious virus particles. The peak viral load of SARS‑CoV‑2 is estimated to occur ~10 days following fever onset, causing patients in the acute stage to be the primary infection source. However, patients in the recovery stage or with occult infections can also be contagious. The host immune response in patients with COVID‑19 remains to be elucidated. By studying other SARS and Middle East respiratory syndrome coronaviruses, it is hypothesized that patients with COVID‑19 may lack sufficient antiviral T‑cell responses, which consequently present with innate immune response disorders. This may to a certain degree explain why this type of CoV triggers severe inflammatory responses and immune damage and its associated complications.

Lactiplantibacillus plantarum as a Potential Adjuvant and Delivery System for the Development of SARS-CoV-2 Oral Vaccines

The most important characteristics regarding the mucosal infection and immune responses against the Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) as well as the current vaccines against coronavirus disease 2019 (COVID-19) in development or use are revised to emphasize the opportunity for lactic acid bacteria (LAB)-based vaccines to offer a valid alternative in the fight against this disease. In addition, this article revises the knowledge on: (a) the cellular and molecular mechanisms involved in the improvement of mucosal antiviral defenses by beneficial Lactiplantibacillus plantarum strains, (b) the systems for the expression of heterologous proteins in L. plantarum and (c) the successful expressions of viral antigens in L. plantarum that were capable of inducing protective immune responses in the gut and the respiratory tract after their oral administration. The ability of L. plantarum to express viral antigens, including the spike protein of SARS-CoV-2 and its capacity to differentially modulate the innate and adaptive immune responses in both the intestinal and respiratory mucosa after its oral administration, indicates the potential of this LAB to be used in the development of a mucosal COVID-19 vaccine.

SARS-CoV-2 and the role of orofecal transmission: a systematic review

Background: Mode of transmission of SARS-CoV-2 is of key public health importance. SARS-CoV-2 has been detected in the feces of some COVID-19 patients, suggesting the possibility that the virus could, in addition to droplet and fomite transmission, be transmitted via the orofecal route. Methods: This review is part of an Open Evidence Review on Transmission Dynamics of COVID-19. We conduct ongoing searches using WHO COVID-19 Database, LitCovid, medRxiv, and Google Scholar; assess study quality based on five criteria and report important findings on an ongoing basis. Where necessary, authors are contacted for further details on the content of their articles. Results: We include searches up until 20 December 2020. We included 110 relevant studies: 76 primary observational studies or reports, and 35 reviews (one cohort study also included a review) examining the potential role of orofecal transmission of SARS-CoV-2. Of the observational studies, 37 were done in China. A total of 48 studies (n=9,081 patients) reported single cases, case series or cohort data on individuals with COVID-19 diagnosis or their contacts and 46 (96%) detected binary RT-PCR with 535 out of 1358 samples positive for SARs-CoV-2 (average 39.4%). The results suggest a long duration of fecal shedding, often recorded after respiratory samples tested negative, and symptoms of gastrointestinal disease were reported in several studies. Twenty-nine studies reported finding SARS-CoV-2 RNA in wastewater, river water or toilet areas. Six studies attempted viral culture from COVID-19 patients' fecal samples: culture was successful in 3 of 6 studies, and one study demonstrated invasion of the virus into the intestinal epithelial cells. Conclusions: Varied observational and mechanistic evidence suggests SARS-CoV-2 can infect and be shed from the gastrointestinal tract, including some data demonstrating viral culture in fecal samples. Future studies should test this hypothesis rigorously to allow the development of appropriate public health measures.

SARS-CoV-2 and the role of orofecal transmission: a systematic review

BACKGROUND

Modes of transmission of SARS-CoV-2 are of key public health importance. SARS-CoV-2 has been detected in the feces of some COVID-19 patients, suggesting the possibility that the virus could, in addition to droplet and fomite transmission, be transmitted via the orofecal route.

METHODS

This review is part of an Open Evidence Review on Transmission Dynamics of COVID-19. We conduct ongoing searches using WHO COVID-19 Database, LitCovid, medRxiv, and Google Scholar; assess study quality based on five criteria and report important findings. Where necessary, authors are contacted for further details on the content of their articles.

RESULTS

We include searches up until 20 December 2020. We included 110 relevant studies: 76 primary observational studies or reports, and 35 reviews (one cohort study also included a review) examining the potential role of orofecal transmission of SARS-CoV-2. Of the observational studies, 37 were done in China. A total of 48 studies (n=9,081 patients) reported single cases, case series or cohort data on individuals with COVID-19 diagnosis or their contacts and 46 (96%) detected binary RT-PCR with 535 out of 1358 samples positive for SARS-CoV-2 (average 39.4%). The results suggest a long duration of fecal shedding, often recorded after respiratory samples tested negative, and symptoms of gastrointestinal disease were reported in several studies. Twenty-nine studies reported finding SARS-CoV-2 RNA in wastewater, river water or toilet areas. Six studies attempted viral culture from COVID-19 patients' fecal samples: culture was successful in 3 of 6 studies, and one study demonstrated invasion of the virus into intestinal epithelial cells.

CONCLUSIONS

Varied observational and mechanistic evidence suggests SARS-CoV-2 can infect and be shed from the gastrointestinal tract, including some data demonstrating viral culture in fecal samples. To fully assess these risks, quantitative data on infectious virus in these settings and infectious dose are needed.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): a Systemic Infection

To date, seven identified coronaviruses (CoVs) have been found to infect humans; of these, three highly pathogenic variants have emerged in the 21st century. The newest member of this group, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first detected at the end of 2019 in Hubei province, China. Since then, this novel coronavirus has spread worldwide, causing a pandemic; the respiratory disease caused by the virus is called coronavirus disease 2019 (COVID-19). The clinical presentation ranges from asymptomatic to mild respiratory tract infections and influenza-like illness to severe disease with accompanying lung injury, multiorgan failure, and death. Although the lungs are believed to be the site at which SARS-CoV-2 replicates, infected patients often report other symptoms, suggesting the involvement of the gastrointestinal tract, heart, cardiovascular system, kidneys, and other organs; therefore, the following question arises: is COVID-19 a respiratory or systemic disease? This review aims to summarize existing data on the replication of SARS-CoV-2 in different tissues in both patients and ex vivo models.

Next-Generation Sequencing Reveals the Progression of COVID-19

The novel coronavirus SARS-CoV-2 (causing the disease COVID-19) has caused a highly transmissible and ongoing pandemic worldwide. Due to its rapid development, next-generation sequencing plays vital roles in many aspects. Here, we summarize the current knowledge on the origin and human transmission of SARS-CoV-2 based on NGS analysis. The ACE2 expression levels in various human tissues and relevant cells were compared to provide insights into the mechanism of SAS-CoV-2 infection. Gut microbiota dysbiosis observed by metagenome sequencing and the immunogenetics of COVID-19 patients according to single-cell sequencing analysis were also highlighted. Overall, the application of these sequencing techniques could be meaningful for finding novel intermediate SARS-CoV-2 hosts to block interspecies transmission. This information will further benefit SARS-CoV-2 diagnostic development and new therapeutic target discovery. The extensive application of NGS will provide powerful support for our fight against future public health emergencies.

Phage Display Technique as a Tool for Diagnosis and Antibody Selection for Coronaviruses

Phage display is one of the important and effective molecular biology techniques and has remained indispensable for research community since its discovery in the year 1985. As a large number of nucleotide fragments may be cloned into the phage genome, a phage library may harbour millions or sometimes billions of unique and distinctive displayed peptide ligands. The ligand–receptor interactions forming the basis of phage display have been well utilized in epitope mapping and antigen presentation on the surface of bacteriophages for screening novel vaccine candidates by using affinity selection-based strategy called biopanning. This versatile technique has been modified tremendously over last three decades, leading to generation of different platforms for combinatorial peptide display. The translation of new diagnostic tools thus developed has been used in situations arising due to pathogenic microbes, including bacteria and deadly viruses, such as Zika, Ebola, Hendra, Nipah, Hanta, MERS and SARS. In the current situation of pandemic of Coronavirus disease (COVID-19), a search for neutralizing antibodies is motivating the researchers to find therapeutic candidates against novel SARS-CoV-2. As phage display is an important technique for antibody selection, this review presents a concise summary of the very recent applications of phage display technique with a special reference to progress in diagnostics and therapeutics for coronavirus diseases. Hopefully, this technique can complement studies on host–pathogen interactions and assist novel strategies of drug discovery for coronaviruses.

TMPRSS11D and TMPRSS13 Activate the SARS-CoV-2 Spike Protein

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) utilizes host proteases, including a plasma membrane-associated transmembrane protease, serine 2 (TMPRSS2) to cleave and activate the virus spike protein to facilitate cellular entry. Although TMPRSS2 is a well-characterized type II transmembrane serine protease (TTSP), the role of other TTSPs on the replication of SARS-CoV-2 remains to be elucidated. Here, we have screened 12 TTSPs using human angiotensin-converting enzyme 2-expressing HEK293T (293T-ACE2) cells and Vero E6 cells and demonstrated that exogenous expression of TMPRSS11D and TMPRSS13 enhanced cellular uptake and subsequent replication of SARS-CoV-2. In addition, SARS-CoV-1 and SARS-CoV-2 share the same TTSPs in the viral entry process. Our study demonstrates the impact of host TTSPs on infection of SARS-CoV-2, which may have implications for cell and tissue tropism, for pathogenicity, and potentially for vaccine development.

Microbiota Modulation of the Gut-Lung Axis in COVID-19

COVID-19 is an infectious disease caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), and according to the World Health Organization (WHO), to date, SARS-CoV-2 has already infected more than 91.8 million people worldwide with 1,986,871 deaths. This virus affects mainly the respiratory system, but the gastrointestinal tract (GIT) is also a target, meanwhile SARS-CoV-2 was already detected in oesophagus, stomach, duodenum, rectum, and in fecal samples from COVID-19 patients. Prolonged GIT manifestations in COVID-19, mainly the diarrhea, were correlated with decreased richness and diversity of the gut microbiota, immune deregulation and delayed SARS-CoV-2 clearance. So, the bidirectional interactions between the respiratory mucosa and the gut microbiota, known as gut-lung axis, are supposed to be involved in the healthy or pathologic immune responses to SARS-CoV-2. In accordance, the intestinal dysbiosis is associated with increased mortality in other respiratory infections, due to an exacerbated inflammation and decreased regulatory or anti-inflammatory mechanisms in the lungs and in the gut, pointing to this important relationship between both mucosal compartments. Therefore, since the mucous membranes from the respiratory and gastrointestinal tracts are affected, in addition to dysbiosis and inflammation, it is plausible to assume that adjunctive therapies based on the modulation of the gut microbiota and re-establishment of eubiosis conditions could be an important therapeutic approach for constraining the harmful consequences of COVID-19. Then, in this review, we summarized studies showing the persistence of SARS-CoV-2 in the gastrointestinal system and the related digestive COVID-19 manifestations, in addition to the literature demonstrating nasopharyngeal, pulmonary and intestinal dysbiosis in COVID-19 patients. Lastly, we showed the potential beneficial role of probiotic administration in other respiratory infections, and discuss the possible role of probiotics as an adjunctive therapy in SARS-CoV-2 infection.

Digestive system involvement of infections with SARS-CoV-2 and other coronaviruses: Clinical manifestations and potential mechanisms

Although coronavirus (CoV) infection is often characterized by respiratory symptoms, the virus can also result in extrapulmonary symptoms, especially the symptoms related to the digestive system. The outbreak of coronavirus disease 2019 (COVID-19) is currently the world’s most pressing public health threat and has a significant impact on civil societies and the global economy. The occurrence of digestive symptoms in patients with COVID-19 is closely related to the development and prognosis of the disease. Moreover, thus far, there are no specific antiviral drug or vaccine approved for the treatment or prevention of COVID-19. Therefore, we elaborate on the effects of CoVs on the digestive system and the potential underlying mechanisms.

International Observational Survey of the Effectiveness of Personal Protective Equipment during Endoscopic Procedures Performed in Patients with COVID-19

INTRODUCTION AND AIMS

This international survey was performed to evaluate the cumulative incidence of nosocomial novel coronavirus disease 2019 (COVID-19) among healthcare professionals during endoscopic procedures.

METHODS

We performed an international web-based self-reported questionnaire survey. Participants completed the questionnaires every week for 12 weeks. The questionnaire elicited responses regarding the development of COVID-19 and details of the personal protective equipment (PPE) used.

RESULTS

All 483 participants were included in the analysis. Participants had a mean age of 42.3 years and comprised 68.3% males. The geographic distribution of the study population was Asia (89.2%), Europe (2.9%), North and South America (4.8%), Oceania (0.6%), and Africa (1.5%). The most common endoscopy-related role of the participants was endoscopist (78.7%), and 74.5% had >10 years of experience. Fourteen participants had performed 83 endoscopic procedures in patients positive for COVID-19. During the mean follow-up period of 4.95 weeks, there were no cases of COVID-19 when treating COVID-19 positive patients. The most common PPE used by participants treating patients with COVID-19 was a surgical mask plus N95 mask plus face shield, goggles, cap, long-sleeved isolation gown, and single pair of gloves. The most common PPE used by participants treating patients without COVID-19 was a surgical mask, no face shield but goggles, cap, long-sleeved isolation gown, and single pair of gloves during all endoscopic procedures.

CONCLUSIONS

The risk of COVID-19 transmission during any endoscopic procedure was low in clinical practice.

Human Intestinal Organoids Recapitulate Enteric Infections of Enterovirus and Coronavirus

Enteroviruses, such as EV-A71 and CVA16, mainly infect the human gastrointestinal tract. Human coronaviruses, including SARS-CoV and SARS-CoV-2, have been variably associated with gastrointestinal symptoms. We aimed to optimize the human intestinal organoids and hypothesize that these optimized intestinal organoids can recapitulate enteric infections of enterovirus and coronavirus. We demonstrate that the optimized human intestinal organoids enable better simulation of the native human intestinal epithelium, and that they are significantly more susceptible to EV-A71 than CVA16. Higher replication of EV-A71 than CVA16 in the intestinal organoids triggers a more vigorous cellular response. However, SARS-CoV and SARS-CoV-2 exhibit distinct dynamics of virus-host interaction; more robust propagation of SARS-CoV triggers minimal cellular response, whereas, SARS-CoV-2 exhibits lower replication capacity but elicits a moderate cellular response. Taken together, the disparate profile of the virus-host interaction of enteroviruses and coronaviruses in human intestinal organoids may unravel the cellular basis of the distinct pathogenicity of these viral pathogens.

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An optimized differentiation protocol improves maturation of intestinal organoids

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SARS-CoV-2 and SARS-CoV infection triggers less robust response than enteroviruses

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Coronaviruses show lower sensitivity to type III IFNs than enteroviruses

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Intestinal organoids recapitulate disparate pathogenicity of CoVs and enteroviruses

Determining available strategies for prevention and therapy: Exploring COVID‑19 from the perspective of ACE2 (Review)

Coronavirus disease 2019 (COVID-19) is an acute infectious pneumonia caused by a novel type of coronavirus infection. There are currently no clinically available specific drugs for the treatment of this virus. The process of host invasion is the key to viral infection, and it is a mechanism that needs to be considered when exploring antiviral drugs. At present, studies have confirmed that angiotensin-converting enzyme II (ACE2) is the main functional receptor through which severe acute respiratory syndrome coronavirus (SARS-CoV-2) invades host cells. Therefore, a number of studies have focused on this field. However, as ACE2 may play a dual role in mediating susceptibility and immunity to SARS-CoV-2 infection, the role of ACE2 in viral infection is controversial. Beginning with the physiological function of ACE2, the present review article summarizes the influence of the ACE2 content on the susceptibility to the virus and acute lung injury. Drug mechanisms were taken as the starting point, combined with the results of clinical trials, specifically elaborating upon and analyzing the efficacy of several ACE2-centered therapeutic drugs and their potential effects. In addition, the current status of ACE2 as a targeted therapy for COVID-19 is discussed in order to provide new insight into the clinical prevention and treatment of COVID-19.

Detection of SARS-CoV-2 RNA in hospital wastewater from a low COVID-19 disease prevalence area

Previous studies on SARS-CoV and MERS-CoV reported the detection of viral RNA in the stool of both symptomatic and asymptomatic individuals. These clinical observations suggest that municipal and hospital wastewater from affected communities may contain SARS-CoV-2 RNA. Recent studies have also reported the presence of SARS-CoV-2 RNA in human feces. Wastewater-based epidemiology (WBE) is a promising approach to understand the prevalence of viruses in a given catchment population, as wastewater contains viruses from symptomatic and asymptomatic individuals. The current study reports the first detection of SARS-CoV-2 RNA in untreated wastewater in Slovenia. Two sizes of centrifugal filters were tested: 30 kDa and 10 kDA AMICON® Ultra-15 Centrifugal Filters, where 10 kDA resulted in a higher concentration factor and higher recovery efficiency. The results in hospital wastewater show that WBE can be used for monitoring COVID -19 and could be applied in municipal wastewater treatment plants as a potential complementary tool for public health monitoring at population level.

Colonic Ileus, Distension, and Ischemia Due to COVID-19-Related Colitis: A Case Report and Literature Review

Coronavirus disease 2019 (COVID-19) predominantly presents with respiratory symptoms, however, the involvement of the gastrointestinal system has also been reported. Isolated gastrointestinal manifestation due to COVID-19 presenting as colonic distension is uncommon. Colonic ileus from COVID-19 infection presents as dilatation on imaging, with the risk of subsequent ischemia and perforation if not recognized and treated promptly. There is no consensus on the treatment modality for COVID-19-related colitis, however, COVID-19-targeted medications in conjunction with surgical intervention have been performed for management. We present a case of a 73-year-old man who presented with abdominal pain, distention, and diarrhea. He tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was found to have marked dilatation of the colon on imaging. He was initially given convalescent plasma to reduce inflammatory markers, as tocilizumab was contraindicated due to suspected bowel obstruction. Once more stable, he underwent surgical intervention followed by tocilizumab infusion. Pathological specimens of the colon demonstrated hemorrhagic colitis with microthrombi suggestive of COVID-19-related colitis.  Recognizing COVID-19-related colitis allows for timely diagnosis and management with targeted interventions in addition to surgery, which may prevent perforation. We suggest convalescent plasma followed by the formation of colostomy and finally infusion of tocilizumab as a feasible option for the treatment of COVID-19-related colitis. However, further research is needed in order to fully understand this entity and provide guidance for its management.

SARS-CoV-2 tropism, entry, replication, and propagation: Considerations for drug discovery and development

Since the initial report of the novel Coronavirus Disease 2019 (COVID-19) emanating from Wuhan, China, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has spread globally. While the effects of SARS-CoV-2 infection are not completely understood, there appears to be a wide spectrum of disease ranging from mild symptoms to severe respiratory distress, hospitalization, and mortality. There are no Food and Drug Administration (FDA)-approved treatments for COVID-19 aside from remdesivir; early efforts to identify efficacious therapeutics for COVID-19 have mainly focused on drug repurposing screens to identify compounds with antiviral activity against SARS-CoV-2 in cellular infection systems. These screens have yielded intriguing hits, but the use of nonhuman immortalized cell lines derived from non-pulmonary or gastrointestinal origins poses any number of questions in predicting the physiological and pathological relevance of these potential interventions. While our knowledge of this novel virus continues to evolve, our current understanding of the key molecular and cellular interactions involved in SARS-CoV-2 infection is discussed in order to provide a framework for developing the most appropriate in vitro toolbox to support current and future drug discovery efforts.

Insights of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) pandemic: a current review

COVID-19, a pandemic of the 21st century caused by novel coronavirus SARS-CoV-2 was originated from China and shallowed world economy and human resource. The medical cures via herbal treatments, antiviral drugs, and vaccines still in progress, and studying rigorously. SARS-CoV-2 is more virulent than its ancestors due to evolution in the spike protein(s), mediates viral attachment to the host's membranes. The SARS-CoV-2 receptor-binding spike domain associates itself with human angiotensin-converting enzyme 2 (ACE-2) receptors. It causes respiratory ailments with irregularities in the hepatic, nervous, and gastrointestinal systems, as reported in humans suffering from COVID-19 and reviewed in the present article. There are several approaches, have been put forward by many countries under the world health organization (WHO) recommendations and some trial drugs were introduced for possible treatment of COVID-19, such as Lopinavir or Ritonavir, Arbidol, Chloroquine (CQ), Hydroxychloroquine (HCQ) and most important Remdesivir including other like Tocilizumab, Oritavancin, Chlorpromazine, Azithromycin, Baricitinib, etc. RT-PCR is the only and early detection test available besides the rapid test kit (serodiagnosis) used by a few countries due to unreasonable causes. Development of vaccine by several leader of pharmaceutical groups still under trial or waiting for approval for mass inoculation. Management strategies have been evolved by the recommendations of WHO, specifically important to control COVID-19 situations, in the pandemic era. This review will provide a comprehensive collection of studies to support future research and enhancement in our wisdom to combat COVID-19 pandemic and to serve humanity.

HIF Prolyl Hydroxylase Inhibitors for COVID-19 Treatment: Pros and Cons

The review analyzes the potential advantages and problems associated with using HIF prolyl hydroxylase inhibitors as a treatment for COVID-19. HIF prolyl hydroxylase inhibitors are known to boost endogenous erythropoietin (Epo) and activate erythropoiesis by stabilizing and activating the hypoxia inducible factor (HIF). Recombinant Epo treatment has anti-inflammatory and healing properties, and thus, very likely, will be beneficial for moderate to severe cases of COVID-19. However, HIF PHD inhibition may have a significantly broader effect, in addition to stimulating the endogenous Epo production. The analysis of HIF target genes reveals that some HIF-targets, such as furin, could play a negative role with respect to viral entry. On the other hand, HIF prolyl hydroxylase inhibitors counteract ferroptosis, the process recently implicated in vessel damage during the later stages of COVID-19. Therefore, HIF prolyl hydroxylase inhibitors may serve as a promising treatment of COVID-19 complications, but they are unlikely to aid in the prevention of the initial stages of infection.

Mucociliary Respiratory Epithelium Integrity in Molecular Defense and Susceptibility to Pulmonary Viral Infections

Mucociliary defense, mediated by the ciliated and goblet cells, is fundamental to respiratory fitness. The concerted action of ciliary movement on the respiratory epithelial surface and the pathogen entrapment function of mucus help to maintain healthy airways. Consequently, genetic or acquired defects in lung defense elicit respiratory diseases and secondary microbial infections that inflict damage on pulmonary function and may even be fatal. Individuals living with chronic and acute respiratory diseases are more susceptible to develop severe coronavirus disease-19 (COVID-19) illness and hence should be proficiently managed. In light of the prevailing pandemic, we review the current understanding of the respiratory system and its molecular components with a major focus on the pathophysiology arising due to collapsed respiratory epithelium integrity such as abnormal ciliary movement, cilia loss and dysfunction, ciliated cell destruction, and changes in mucus rheology. The review includes protein interaction networks of coronavirus infection-manifested implications on the molecular machinery that regulates mucociliary clearance. We also provide an insight into the alteration of the transcriptional networks of genes in the nasopharynx associated with the mucociliary clearance apparatus in humans upon infection by severe acute respiratory syndrome coronavirus-2.

Multi-Organ Involvement in COVID-19: Beyond Pulmonary Manifestations

Coronavirus Disease 19 (COVID-19), due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has become an on-going global health emergency affecting over 94 million cases with more than 2 million deaths globally. Primarily identified as atypical pneumonia, it has developed into severe acute respiratory distress syndrome (ARDS), a multi-organ dysfunction with associated fatality. Ever since its emergence, COVID-19 with its plethora of clinical presentations has signalled its dynamic nature and versatility of the disease process. Being a disease with droplet transmission has now assumed the proportion of a suspected airborne nature which, once proved, poses a Herculean task to control. Because of the wide distribution of the human angiotensin-converting enzyme-2 (hACE2) receptors, known for its transmission, we envisage its multiorgan spread and extensive disease distribution. Thus, an extensive review of the extrapulmonary organotropism of SARS-CoV-2 with organ-specific pathophysiology and associated manifestations like dermatological complications, myocardial dysfunction, gastrointestinal symptoms, neurologic illnesses, hepatic and renal injury is needed urgently. The plausible mechanism of site-specific viral invasion is also discussed to give a comprehensive understanding of disease complexity, to help us to focus on research priorities and therapeutic strategies to counter the disease progression. A note on the latest advancements in vaccine research will enlighten the scientific world and equip it for better preparedness.

SARS-CoV-2 RNA detection in stool samples from acute gastroenteritis cases, Brazil

We described the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in stool samples from patients presenting only acute gastroenteritis (AGE) symptoms. From January to July 2020, 121 AGE stool samples were screened by quantitative reverse-transcription polymerase chain reaction. We detected SARS-CoV-2 in 27.5% of samples received during the epidemic period. No infectious viruses were observed in Vero E6 cells.

Considerations for Gut Microbiota and Probiotics in Patients with Diabetes Amidst the Covid-19 Pandemic: A Narrative Review

Objective: To review data implicating microbiota influences on Coronavirus Disease 2019 (COVID-19) in patients with diabetes.

Methods: Primary literature review included topics: “COVID-19,” “SARS,” “MERS,” “gut micro-biota,” “probiotics,” “immune system,” “ACE2,” and “metformin.”

Results: Diabetes was prevalent (~11%) among COVID-19 patients and associated with increased mortality (about 3-fold) compared to patients without diabetes. COVID-19 could be associated with worsening diabetes control and new diabetes diagnosis that could be linked to high expression of angiotensin-converting enzyme 2 (ACE2) receptors (coronavirus point of entry into the host) in the endocrine pancreas. A pre-existing gut microbiota imbalance (dysbiosis) could contribute to COVID-19–related complications in patients with diabetes. The COVID-19 virus was found in fecal samples (~55%), persisted for about 5 weeks, and could be associated with diarrhea, suggesting a role for gut dysbiosis. ACE2 expressed on enterocytes and colonocytes could serve as an alternative route for acquiring COVID-19. Experimental models proposed some probiotics, including Lactobacillus casei, L. plantarum, and L. salivarius, as vectors for delivering or enhancing efficacy of anti-coronavirus vaccines. These Lactobacillus probiotics were also beneficial for diabetes. The potential mechanisms for interconnections between coronavirus, diabetes, and gut microbiota could be related to the immune system, ACE2 pathway, and metformin treatment. There were suggestions but no proof supporting probiotics benefits for COVID-19 infection.

Conclusion: The data suggested that the host environment including the gut microbiota could play a role for COVID-19 in patients with diabetes. It is a challenge to the scientific community to investigate the beneficial potential of the gut microbiota for strengthening host defense against coronavirus in patients with diabetes.

Angiotensin-converting enzyme 2 and COVID-19 in cardiorenal diseases

The rapid spread of the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has brought into focus the key role of angiotensin-converting enzyme 2 (ACE2), which serves as a cell surface receptor required for the virus to enter cells. SARS-CoV-2 can decrease cell surface ACE2 directly by internalization of ACE2 bound to the virus and indirectly by increased ADAM17 (a disintegrin and metalloproteinase 17)-mediated shedding of ACE2. ACE2 is widely expressed in the heart, lungs, vasculature, kidney and the gastrointestinal (GI) tract, where it counteracts the deleterious effects of angiotensin II (AngII) by catalyzing the conversion of AngII into the vasodilator peptide angiotensin-(1-7) (Ang-(1-7)). The down-regulation of ACE2 by SARS-CoV-2 can be detrimental to the cardiovascular system and kidneys. Further, decreased ACE2 can cause gut dysbiosis, inflammation and potentially worsen the systemic inflammatory response and coagulopathy associated with SARS-CoV-2. This review aims to elucidate the crucial role of ACE2 both as a regulator of the renin-angiotensin system and a receptor for SARS-CoV-2 as well as the implications for Coronavirus disease 19 and its associated cardiovascular and renal complications.

The Strategy of Boosting the Immune System Under the COVID-19 Pandemic

The novel coronavirus (SARS-CoV-2) infection (COVID-19) has raised considerable concern on the entire planet. On March 11, 2020, COVID-19 was categorized by the World Health Organization (WHO) as a pandemic infection, and by March 18, 2020, it has spread to 146 countries. The first internal defense line against numerous diseases is personalized immunity. Although it cannot be claimed that personalized nutrition will have an immediate impact on a global pandemic, as the nutritional interventions required a long time to induce beneficial outcomes on immunity development, nutritional strategies are still able to clarify and have a beneficial influence on the interplay between physiology and diet, which could make a positive contribution to the condition in the next period. As such, a specific goal for every practitioner is to evaluate different tests to perceive the status of the patient, such as markers of inflammation, insulin regulation, and nutrient status, and to detect possible imbalances or deficiencies. During the process of disease development, the supplementation and addition of different nutrients and nutraceuticals can influence not only the viral replication but also the cellular mechanisms. It is essential to understand that every patient has its individual needs. Even though many nutrients, nutraceuticals, and drugs have beneficial effects on the immune response and can prevent or ameliorate viral infections, it is essential to detect at what stage in COVID-19 progression the patient is at the moment and decide what kind of nutrition intervention is necessary. Furthermore, understanding the pathogenesis of coronavirus infection is critical to make proper recommendations.

COVID-19: What Should the General Practitioner Know?

BACKGROUND

SARS-CoV-2 infection is currently the most significant public health challenge. Its presentation ranges from mild to severe respiratory failure and septic shock. Rapid transmission of the virus is dangerous with a high possibility of life-threatening complications. Lack of treatment standards for SARS-CoV-2 is responsible for the current dilemma in clinical medicine.

METHODS

An electronic literature search was done using PubMed to gather information on the pathogenesis, transmission of infection, clinical symptoms, diagnosis, and therapeutic options for COVID-19. Search items included "SARS-CoV-2", "COVID-19" and "coronavirus infection".

RESULTS

In light of the current global crisis caused by SARS-CoV-2, the exchange of information within the scientific community should be quick and extremely transparent. Thus, this review presents the available information necessary for a general practitioner. Such presentation of data should allow the reader quick access to basic and crucial information related to epidemiology, viral transmission, clinical symptoms, diagnostics, treatment, and complications that may occur in the course of COVID-19.

CONCLUSION

Rapidly increasing amounts of information about the diagnosis and treatment of patients with SARS-CoV-2 allow a better understanding of the etiology and course of the infection. In the current epidemiological situation, readily accessible information helps minimize the time to acquire knowledge and focus on prevention methods, diagnostic and treatment options. Thus, this review highlights key issues related to SARS-CoV-2 infection and contains the most useful data for daily medical practice.

COVID-19: An overview and a clinical update

The outbreak of coronavirus disease-2019 (COVID-19, previously known as 2019 nCoV) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Wuhan City, China, has spread rapidly around the world. Most patients from the first cluster had an epidemiological connection to the Wuhan's Huanan Seafood Wholesale Market. Available evidence has shown that SARS-CoV-2 can be easily transmitted from person to person through close contact and respiratory droplets, posing a substantial challenge to public health. At present, the research on SARS-CoV-2 is still in the primary stages. However, dexa-methasone and remdesivir are appeared to be promising medical therapies. Still, there is no definite specific treatment, and the mainstay of treatment is still focused on supportive therapies. Currently, over 150 vaccines are under investigation. It is necessary to understand the nature of the virus and its clinical characteristics in order to find effectively manage the disease. The knowledge about this virus is rapidly evolving, and clinicians must update themselves regularly. The present review comprehensively summarizes the epidemiology, pathogenesis, clinical characteristics, and management of COVID-19 based on the current evidence.

Diarrhea Is Associated with Increased Severity of Disease in COVID-19: Systemic Review and Metaanalysis

COVID-19 has become a pandemic since its emergence in Wuhan, China. The disease process was initially defined by presence of respiratory symptoms; however, it is now well studied and shown in evidence that this is a multisystem process. Involvement of gastrointestinal (GI) system has been identified, and GI symptoms can be the only presenting symptoms in some patients. Hence, it is important to identify and understand the GI symptoms associated with COVID-19 for appropriate care of patient. We conducted a systematic review and metaanalysis to identify the GI symptoms of COVID-19 and identify association of diarrhea with severity of COVID-19. We performed extensive search of Medline and Embase from December 2019 to May 2020 to identify articles reporting GI symptoms in COVID-19 patients. The primary outcome was prevalence of GI symptoms in COVID-19 patients, and secondary outcome was the association of diarrhea with disease severity. A total of 38 studies with 8407 patients were included. Of the total patients, 15.47% patients had at least one GI symptom. The pooled prevalence of nausea/vomiting was 7.53% and diarrhea was 11.52%. On metaanalysis, patients with diarrhea as one of the presenting symptoms were more likely to have severe disease (OR 1.63, 95% CI: 1.11-3.38, p = 0.01). Our systematic review and metaanalysis demonstrated that GI symptoms are common in COVID-19. Presence of diarrhea as a presenting symptom is associated with increased disease severity and likely worse prognosis. Early recognition of patients is needed for prompt management of this at-risk population.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s42399-020-00662-w.

High anal swab viral load predisposes adverse clinical outcomes in severe COVID-19 patients

To identify the association between the kinetics of viral load and clinical outcome in severe coronavirus disease 2019 (COVID-19) patients, a retrospective study was performed by involved 188 hospitalized severe COVID-19 patients in the LOTUS China trial. Among the collected 578 paired throat swab (TS) and anal swab (AS) samples, viral RNA was detected in 193 (33.4%) TS and 121 (20.9%) AS. A higher viral RNA load was found in TS than that of AS, with means of 1.0 × 10⁶ and 2.3 × 10⁵ copies/ml, respectively. In non-survivors, the viral RNA in AS was detected earlier than that in survivors (median of 14 days vs 19 days, P = 0.007). The positivity and viral load in AS were higher in non-survivors than that of survivors at week 2 post symptom onset (P = 0.006). A high initial viral load in AS was associated with death (OR 1.368, 95% CI 1.076–1.741, P = 0.011), admission to the intensive care unit (OR 1.237, 95% CI 1.001–1.528, P = 0.049) and need for invasive mechanical ventilation (OR 1.340, 95% CI 1.076–1.669, P = 0.009). Our findings indicated viral replication in extrapulmonary sites should be monitored intensively during antiviral therapy.

Gordian Knot: Gastrointestinal lesions caused by three highly pathogenic coronaviruses from SARS-CoV and MERS-CoV to SARS-CoV-2

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen of 2019 novel coronavirus disease (COVID-19), is currently spreading around the world. The WHO declared on January 31 that the outbreak of SARS-CoV-2 was a public health emergency. SARS-Cov-2 is a member of highly pathogenic coronavirus group that also consists of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Although respiratory tract lesions were regarded as main manifestation of SARS-Cov-2 infection, gastrointestinal lesions were also reported. Similarly, patients with SARS-CoV and MERS-CoV were also observed. Common gastrointestinal symptoms of patients mainly included diarrhea, vomiting and abdominal pain. Gastrointestinal lesions could be used as basis for early diagnosis of patients, and at the same time, controlling gastrointestinal lesions better facilitated to cut off the route of fecal-oral transmission. Hence, this review summarizes the characteristics and mechanism of gastrointestinal lesions caused by three highly pathogenic human coronavirus infections including SARS-CoV, MERS-CoV, as well as SARS-CoV-2. Furthermore, it is expected to gain experience from gastrointestinal lesions caused by SARS-CoV and MERS-CoV infections in order to be able to better relieve SARS-CoV-2 epidemic. Targetin gut microbiota to regulate the process of SARS-CoV-2 infection should be a concern. Especially, the application of nanotechnology may provide help for further controlling COVID-19.

Product of natural evolution (SARS, MERS, and SARS-CoV-2); deadly diseases, from SARS to SARS-CoV-2

SARS-CoV-2, the virus causing COVID-19, is a single-stranded RNA virus belonging to the order Nidovirales, family Coronaviridae, and subfamily Coronavirinae. SARS-CoV-2 entry to cellsis initiated by the binding of the viral spike protein (S) to its cellular receptor. The roles of S protein in receptor binding and membrane fusion makes it a prominent target for vaccine development. SARS-CoV-2 genome sequence analysis has shown that this virus belongs to the beta-coronavirus genus, which includes Bat SARS-like coronavirus, SARS-CoV and MERS-CoV. A vaccine should induce a balanced immune response to elicit protective immunity. In this review, we compare and contrast these three important CoV diseases and how they inform on vaccine development.

Clinical implication and risk factor of pneumonia development in mild coronavirus disease 2019 patients

BACKGROUND/AIMS

Although a majority of coronavirus disease 2019 (COVID-19) cases were characterized as mild, data assessing the development of pneumonia in mild COVID-19 patients are limited. We aimed to examine the effect of pneumonia development on the clinical course of mild COVID-19 in hospitalized patients.

METHODS

A retrospective cohort study was conducted via medical record review between February 25, 2020 and April 11, 2020 at a single center. The impact of pneumonia development on the time to viral clearance in mild COVID-19 patients was evaluated. Risk factors associated with the development of pneumonia were also identified.

RESULTS

Chest radiographs revealed the development of pneumonia in 26.8% of mild COVID-19 patients. The time to pneumonia development was a median of 8.0 days from the onset of symptoms and 3.5 days after hospital admission. A multivariate analysis for predicting pneumonia development identified age ≥ 65 years (odds ratio [OR], 3.15; 95% confidence interval [CI], 1.14 to 8.73), cough (OR, 2.18; 95% CI, 1.29 to 3.68), dyspnea (OR, 3.58; 95% CI, 1.10 to 11.69), and diarrhea (OR, 2.69; 95% CI, 1.51 to 4.78) as significant variables. The time to negative conversion was longer in mild COVID-19 patients who developed pneumonia (23.6 days vs. 18.4 days, p = 0.003). In Kaplan-Meier estimation and multivariate Cox regression analyses, newly developed pneumonia was significantly related with delayed time to negative conversion (log-rank test, p = 0.02; hazard ratio, 2.90; 95% CI, 1.06 to 7.97).

CONCLUSION

The development of pneumonia delayed viral clearance in patients with mild COVID-19. Elderly patients or those suffering from diarrhea should be closely monitored, given the increased risk of developing pneumonia.

Survival of SARS-COV-2 in untreated and treated wastewater—a review

In the current scenario of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic, a review on the survival of this novel virus in treated and untreated wastewater is proposed. Other coronavirus species are known to survive in wastewater for days to weeks. Present data also shows that SARS-CoV-2 can be present in waste product generated by infected humans. This generated waste can be source of this virus to wastewater stream and being an enveloped virus can survive for longer period, which can be aerosolized and act as secondary transmission source to human exposure. The study reports different wastewater treatment process considered for the removal of this virus and a few studies have made with 100% removal. Thus, it is advisable to adopt the mechanisms, which report 100% removal of the virus from wastewater in order to stop the spread of the virus. Here we suggest this pathway of transmission should be rigorously studied, especially in countries like India, where minimum hygiene and sanitation can be tough to achieve because of high population density. We further suggest looking into major issues to be expected especially in developing countries and future researches need to be focused to minimize the transmission of this lethal virus.

Recent Advances in Endoscope Disinfection: Where Do We Stand in the COVID era?

Over 16 million cases worldwide, severe acute respiratory syndrome coronavirus 2 has profoundly affected healthcare as we know it. Given reports of gastrointestinal involvement and viral shedding in the stool, it is unsurprising there are concerns that endoscopic equipment may be a potential vector of viral transmission. Here, we provide an overview of existing practices for endoscope reprocessing, recent developments in the field, and challenges in the COVID-19 environment. Current multi-society guidelines do not advise any change to endoscope disinfection protocols but emphasize strict adherence to recommended practices. However, endoscopy reprocessing staff may benefit from supplemental personal protective equipment measures, especially in high risk situations. Because thorough endoscope reprocessing is highly operator dependent, adequate training of personnel is critical for proper manual cleaning and disinfection of endoscopes that have potential to harbor virus. Bacterial contamination of duodenoscopes has caused outbreaks of infection from multidrug-resistant organisms, highlighting vulnerable areas. The emphasis of current studies is on optimization of disinfection and drying, minimization of simethicone use, and on quality control of endoscope reprocessing with sampling and microbiological culturing. Recent advances include novel approaches to endoscope sterilization, infection barrier methods, and design of partially or fully disposable duodenoscopes. Overall, the available data indicate that, when correctly executed, current reprocessing practices are sufficient in preventing SARS-COV-2 transmission.

Gastrointestinal Bleeding, but Not Other Gastrointestinal Symptoms, Is Associated With Worse Outcomes in COVID-19 Patients

Background: Patients with coronavirus disease 2019 (COVID-19) can present with gastrointestinal (GI) symptoms. However, the prevalence of GI symptoms and their association with outcomes remain controversial in COVID-19 patients. Methods: All COVID-19 patients consecutively admitted to the Wuhan Huoshenshan hospital from February 2020 to April 2020 were collected. Disease severity and outcomes were compared between COVID-19 patients with and without GI symptoms. Logistic regression analyses were performed to evaluate the association of GI symptoms with the composite endpoint and death in COVID-19 patients. A composite endpoint was defined as transfer to intensive care unit, requirement of mechanical ventilation, and death. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results: Overall, 2,552 COVID-19 patients were included. The prevalence of GI symptoms was 21.0% (537/2,552). Diarrhea (8.9%, 226/2,552) was the most common GI symptom. Patients with GI symptoms had significantly higher proportions of severe COVID-19 and worse outcomes than those without. Univariate logistic regression analyses demonstrated that GI symptoms were significantly associated with the composite endpoint (OR = 2.426, 95% CI = 1.608-3.661; P < 0.001) and death (OR = 2.137, 95% CI = 1.209-3.778; P = 0.009). After adjusting for age, sex, and severe/critical COVID-19, GI symptoms were still independently associated with the composite endpoint (OR = 2.029, 95% CI = 1.294-3.182; P = 0.002), but not death (OR = 1.726, 95% CI = 0.946-3.150; P = 0.075). According to the type of GI symptoms, GI bleeding was an independent predictor of the composite endpoint (OR = 8.416, 95% CI = 3.465-20.438, P < 0.001) and death (OR = 6.640, 95% CI = 2.567-17.179, P < 0.001), but not other GI symptoms (i.e., diarrhea, abdominal discomfort, nausea and/or vomiting, constipation, acid reflux and/or heartburn, or abdominal pain). Conclusion: GI symptoms are common in COVID-19 patients and may be associated with their worse outcomes. Notably, such a negative impact of GI symptoms on the outcomes should be attributed to GI bleeding.

Outcomes and prognostic factors in 70 non-survivors and 595 survivors with COVID-19 in Wuhan, China

Since the first outbreak of coronavirus disease 2019 (COVID-19) occurred in December 2019, more than 51 million cases had been reported globally. We aimed to identify the risk factors for in-hospital fatal outcome and severe pneumonia of this disease. This is a retrospective, multicentre study, which included all confirmed cases of COVID-19 with definite outcomes (died or discharged) hospitalized between 1 January and 4 March 2020 in Wuhan. Of all 665 patients included, 70 died and 595 discharged (including 333 mild and 262 severe cases). Underlying comorbidity was more commonly observed among deaths (72.9%) than mild (26.4%) and severe (61.5%) survivors, with hypertension, diabetes and cardiovascular as dominant diseases. Fever and cough were the primary clinical magnifications. Older age (≥65 years) (OR = 3.174, 95% CI = 1.356-7.755), diabetes (OR = 2.540, 95% CI = 0.995-6.377), dyspnoea (OR = 7.478, 95% CI = 3.031-19.528), respiratory failure (OR = 10.528, 95% CI = 4.484-25.829), acute cardiac injury (OR = 25.103, 95% CI = 9.057-76.590) and acute respiratory distress syndrome (OR = 7.308, 95% CI = 1.501-46.348) were associated with in-hospital fatal outcome. In addition, older age (OR = 2.149, 95% CI = 1.424-3.248), diabetes (OR = 3.951, 95% CI = 2.077-7.788), cardiovascular disease (OR = 3.414, 95% CI = 1.432-8.799), nervous system disease (OR = 4.125, 95% CI = 1.252-18.681), dyspnoea (OR = 31.944, 95% CI = 18.877-92.741), achieving highest in-hospital temperature of >39.0°C (OR = 37.450, 95% CI = 7.402-683.403) and longer onset of illness to diagnosis (≥9 days) were statistically associated with higher risk of developing severe COVID-19. In conclusion, the potential risk factors forolder age, diabetes, dyspnoea, respiratory failure, acute cardiac injury and acute respiratory distress syndrome could help clinicians to identify patients with poor prognosis at an early stage.

Road Map to Understanding SARS-CoV-2 Clinico-Immunopathology and COVID-19 Disease Severity

SARS-CoV-2, a novel coronavirus, was first identified in Wuhan, China in December 2019. The rapid spread of the virus worldwide prompted the World Health Organization (WHO) to declare COVID-19 a pandemic in March 2020. COVID-19 discontinuing's a global health crisis. Approximately 80% of the patients infected with SARS-CoV-2 display undetectable to mild inflammation confined in the upper respiratory tract. In remaining patients, the disease turns into a severe form affecting almost all major organs predominantly due to an imbalance of innate and adaptive arms of host immunity. The purpose of the present review is to narrate the virus's invasion through the system and the host's reaction. A thorough discussion on disease severity is also presented regarding the behavior of the host's immune system, which gives rise to the cytokine storm particularly in elderly patients and those with comorbidities. A multifaceted yet concise description of molecular aspects of disease progression and its repercussion on biochemical and immunological features in infected patients is tabulated. The summary of pathological, clinical, immunological, and molecular accounts discussed in this review is of theranostic importance to clinicians for early diagnosis of COVID-19 and its management.

Coronavirus genomes carry the signatures of their habitats

Coronaviruses such as SARS-CoV-2 regularly infect host tissues that express antiviral proteins (AVPs) in abundance. Understanding how they evolve to adapt or evade host immune responses is important in the effort to control the spread of infection. Two AVPs that may shape viral genomes are the zinc finger antiviral protein (ZAP) and the apolipoprotein B mRNA editing enzyme-catalytic polypeptide-like 3 (APOBEC3). The former binds to CpG dinucleotides to facilitate the degradation of viral transcripts while the latter frequently deaminates C into U residues which could generate notable viral sequence variations. We tested the hypothesis that both APOBEC3 and ZAP impose selective pressures that shape the genome of an infecting coronavirus. Our investigation considered a comprehensive number of publicly available genomes for seven coronaviruses (SARS-CoV-2, SARS-CoV, and MERS infecting Homo sapiens, Bovine CoV infecting Bos taurus, MHV infecting Mus musculus, HEV infecting Sus scrofa, and CRCoV infecting Canis lupus familiaris). We show that coronaviruses that regularly infect tissues with abundant AVPs have CpG-deficient and U-rich genomes; whereas those that do not infect tissues with abundant AVPs do not share these sequence hallmarks. Among the coronaviruses surveyed herein, CpG is most deficient in SARS-CoV-2 and a temporal analysis showed a marked increase in C to U mutations over four months of SARS-CoV-2 genome evolution. Furthermore, the preferred motifs in which these C to U mutations occur are the same as those subjected to APOBEC3 editing in HIV-1. These results suggest that both ZAP and APOBEC3 shape the SARS-CoV-2 genome: ZAP imposes a strong CpG avoidance, and APOBEC3 constantly edits C to U. Evolutionary pressures exerted by host immune systems onto viral genomes may motivate novel strategies for SARS-CoV-2 vaccine development.

An ACE2 Microbody Containing a Single Immunoglobulin Fc Domain Is a Potent Inhibitor of SARS-CoV-2

Soluble forms of angiotensin-converting enzyme 2 (ACE2) have recently been shown to inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We report on an improved soluble ACE2, termed a "microbody," in which the ACE2 ectodomain is fused to Fc domain 3 of the immunoglobulin (Ig) heavy chain. The protein is smaller than previously described ACE2-Ig Fc fusion proteins and contains an H345A mutation in the ACE2 catalytic active site that inactivates the enzyme without reducing its affinity for the SARS-CoV-2 spike. The disulfide-bonded ACE2 microbody protein inhibits entry of SARS-CoV-2 spike protein pseudotyped virus and replication of live SARS-CoV-2 in vitro and in a mouse model. Its potency is 10-fold higher than soluble ACE2, and it can act after virus bound to the cell. The microbody inhibits the entry of β coronaviruses and virus with the variant D614G spike. The ACE2 microbody may be a valuable therapeutic for coronavirus disease 2019 (COVID-19) that is active against viral variants and future coronaviruses.

Skin and gastrointestinal symptoms in COVID-19

INTRODUCTION

The first cases of coronavirus disease 2019 (COVID-19) were noted in December 2019 in Wuhan province, China. The World Health Organisation (WHO) announced the pandemic status on March 11, 2020. The manifestations of the disease are as follows: fever, cough, fatigue, anosmia and ageusia, dyspnoea, chest pain, muscle soreness, chills, sore throat, rhinitis, headache, gastrointestinal (GI) symptoms, and dermal lesions.

AIM

To evaluate the relationship between dermal lesions and GI symptoms in a group of COVID-19 patients.

MATERIAL AND METHODS

A group of 441 COVID-19 patients admitted to the Central Clinical Hospital of the Ministry of the Interior and Administration in Warsaw between March 15th and June 15th, 2020.

RESULTS

Of 441 patients with confirmed SARS-CoV-2 infection, 255 (58.5%) experienced gastrointestinal (GI) symptoms: lack of appetite was reported in 124 (48.6%) cases, diarrhoea was noted in 109 (42.7%), abdominal pain in 95 (37.3%), vomiting in 37 (14.5%), and nausea in 32 (12.5%) cases. Eight (1.81%) patients had dermal lesions: erythematous macular lesions (2 patients - 25%), erythematous infiltrated lesions (2; 25%), erythematous infiltrated and exfoliative lesions (3; 37.5%), erythematous papular lesions (3; 37.5%), and erythematous oedematous lesions (2; 25%). All of those patients reported gastrointestinal symptoms during the hospitalisation.

CONCLUSIONS

The following study analyses possible causes of dermal lesions and their coexistence with GI symptoms. Several possible theories were taken into account, including the microbiota alterations and issue of drug-related complications.

The preliminary comparative results between Covid-19 and non-Covid-19 patients in Western China

BACKGROUND

This study aims to investigate the comparative clinical characteristics of Covid-19 and non-Covid-19 patients.

METHODS

Fifteen Covid-19 and 93 non-Covid-19 patients were included in RNA testing. All epidemiological and clinical data were collected and analyzed, and then comparative results were carried out.

RESULTS

Covid-19 patients were older (46.40 ± 18.21 years vs 34.43 ± 18.80 years) and had a higher body weight (70.27 ± 10.67 kg vs 60.54 ± 12.33 kg, P < 0.05). The main symptoms that were similar between Covid-19 and non-Covid-19 patients, and Covid-19 patients showed a lower incidence of sputum production (6.67% vs 45.16%, P < 0.01) and a lower white-cell count (4.83 × 10⁹/L vs 7.43 × 10⁹/L) and lymphocyte count (0.90 × 10⁹/L vs 1.57 × 10⁹/L, P < 0.01). Although there were no differences, C-reactive protein and interleukin-6 were elevated in Covid-19 patients. The sensitivity and negative predictive value of CT images were 0.87 and 0.97, respectively. Covid-19 patients showed a higher contact history of Wuhan residents (80% vs 30.11%) and higher familial clustering (53.33% vs 8.60%, P < 0.001). Covid-19 patients showed a higher major adverse events (ARDS, 13.33%; death, 6.67%; P < 0.05).

CONCLUSION

Our results suggested that Covid-19patients had a significant history of exposure and familial clustering and a higher rate of severe status; biochemical indicators showed lymphocyte depletion.

Persistent Detection and Infectious Potential of SARS-CoV-2 Virus in Clinical Specimens from COVID-19 Patients

The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) that emerged in December 2019 as the causative agent of Coronavirus 2019 (COVID-19) and was declared a pandemic by the World Health Organization in March 2020 has several distinctive features, including extensive multiorgan involvement with a robust systemic inflammatory response, significant associated morbidity and mortality, and prolonged persistence of viral RNA in the clinical specimens of infected individuals as detected by Reverse Transcription Polymerase Chain Reaction (RT-PCR) amplification. This review begins with an overview of SARS-CoV-2 morphology and replication and summarizes what is known to date about the detection of the virus in nasal, oropharyngeal, and fecal specimens of patients who have recovered from COVID-19, with a focus on the factors thought to contribute to prolonged detection. This review also provides a discussion on the infective potential of this material from asymptomatic, pre-symptomatic, and convalescing individuals, to include a discussion of the relative persistence and infectious potential of virus in clinical specimens recovered from pediatric COVID-19 patients.

Prospects for mucosal vaccine: shutting the door on SARS-CoV-2

The sudden emergence of a highly transmissible and pathogenic coronavirus SARS-CoV-2 in December 2019 from China and its rapid global spread has posed an international health emergency. The rapid development of an effective vaccine is imperative to control the spread of SARS-CoV-2. A number of concurrent efforts to find an effective therapeutic agent or vaccine for COVID-19 (coronavirus disease 2019) are being undertaken globally. Oral and nasal mucosal surfaces serve as the primary portal of entry for pathogens like coronaviruses in the human body. As evidenced by studies on similar coronaviruses (SARS-CoV and MERS-CoV), mucosal vaccination can provide a safe and effective means for the induction of long-lasting systemic and mucosal immunity to confer protection against SARS-CoV-2. This article summarizes the approaches to an effective mucosal vaccine formulation which can be a rewarding approach to combat the unprecedented threat posed by this emerging global pandemic.