Enteric involvement of severe acute respiratory syndrome-associated coronavirus infection

COVID-19: from an acute to chronic disease? Potential long-term health consequences

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite pulmonary impairments being the most prevalent, extra-pulmonary manifestations of COVID-19 are abundant. Confirmed COVID-19 cases have now surpassed 57.8 million worldwide as of 22 November 2020. With estimated case fatality rates (number of deaths from COVID-19 divided by number of confirmed COVID-19 cases) varying between 1 and 7%, there will be a large population of recovered COVID-19 patients that may acquire a multitude of long-term health consequences. While the multi-organ manifestations of COVID-19 are now well-documented, the potential long-term implications of these manifestations remain to be uncovered. In this review, we turn to previous similar coronaviruses (i.e. SARS-CoV-1 and Middle East respiratory syndrome coronavirus [MERS-CoV]) in combination with known health implications of SARS-CoV-2 infection to predict potential long-term effects of COVID-19, including pulmonary, cardiovascular, hematologic, renal, central nervous system, gastrointestinal, and psychosocial manifestations, in addition to the well-known post-intensive care syndrome. It is necessary to monitor COVID-19 patients after discharge to understand the breadth and severity of long-term effects. This can be accomplished by repurposing or initiating large cohort studies to not only focus on the long-term consequences of SARS-CoV-2 infection, but also on acquired immune function as well as ethno-racial group and household income disparities in COVID-19 cases and hospitalizations. The future for COVID-19 survivors remains uncertain, and if this virus circulates among us for years to come, long-term effects may accumulate exponentially.

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.

Ischemic gastrointestinal complications of COVID-19: a systematic review on imaging presentation

Background

Limited data is available addressing gastrointestinal (GI) ischemia in coronavirus disease 2019 (COVID-19). We reviewed the clinical and radiologic features of GI ischemia and its related complications in thirty-one COVID-19 patients reported in literature.

Methods

A systematic literature review was performed using a search strategy on all studies published from January 1, 2020, to June 13, 2020, and updated on September 6, 2020, on databases from PubMed, Scopus, Embase, Web of Science, and Google Scholar. Every study with at least one presentation of COVID-19-related GI ischemia complication and one GI imaging finding was included.

Results

In total, twenty-two studies and thirty-one patients with the mean age of 59 ± 12.7 (age range: 28–80) years old were included, of which 23 (74.2%) patients were male, 7 (22.5%) female, and one unknown gender. The significant GI imaging findings include mesenteric arterial or venous thromboembolism, followed by small bowel ischemia. Nine patients (29%) presented with arterial compromise due to superior mesenteric thromboembolism, resulting in bowel ischemia. Also, 6 patients (19.3%) demonstrated occlusive thrombosis of the portal system and superior mesenteric vein. More than two-thirds of patients (20, 64.5%) required laparotomy and bowel resection. Eventually, five (16.1%) patients were discharged, of whom four cases (12.9%) readmitted. Five (16.1%) patients remained ICU hospitalized at the report time and 12 (38.7%) patients died.

Conclusion

Macrovascular arterial/venous thrombosis is identified in almost half of COVID-19 patients with bowel ischemia. Overall mortality in COVID-19 patients with GI ischemia and radiologically evident mesenteric thrombotic occlusion was 38.7% and 40%, retrospectively.

Postoperative Onset and Detection of SARS-CoV-2 in Surgically Resected Specimens From Gastrointestinal Cancer Patients With Pre/Asymptomatic COVID-19

OBJECTIVE

To describe the epidemiologic features and clinical courses of gastrointestinal cancer patients with pre/asymptomatic COVID-19 and to explore evidence of SARS-CoV-2 in the surgically resected specimens.

SUMMARY BACKGROUND DATA

The advisory of postponing or canceling elective surgeries escalated a worldwide debate regarding the safety and feasibility of performing elective surgical procedures during this pandemic. Limited data are available on gastrointestinal cancer patients with pre/asymptomatic COVID-19 undergoing surgery.

METHODS

Clinical data were retrospectively collected and analyzed. Surgically resected specimens of the cases with confirmed COVID-19 were obtained to detect the expression of ACE2 and the presence of SARS-CoV-2.

RESULTS

A total of 52 patients (male, 34) with a median age 62.5 years were enrolled. All the patients presented no respiratory symptoms or abnormalities on chest computed tomography before surgery. Six patients (11.5%) experienced symptom onset and were confirmed to be COVID-19. All were identified to be preoperatively pre/asymptomatic, as 5 were with SARS-CoV-2 presenting in cytoplasm of enterocytes or macrophages from the colorectal tissues and 1 had symptom onset immediately after surgery. The case fatality rate in patients with COVID-19 was 16.7%, much higher than those without COVID-19 (2.2%).

CONCLUSIONS

Gastrointestinal cancer patients with pre/asymptomatic COVID-19 were at high risk of postoperative onset and death. At current pandemic, elective surgery should be postponed or canceled. It highlights the need for investigating the full clinical spectrum and natural history of this infection. The early colorectal tropism of SARS-CoV-2 may have major implications on prevention, diagnosis, and treatment of COVID-19.

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.

Mechanisms of SARS-CoV-2 Transmission and Pathogenesis

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) marks the third highly pathogenic coronavirus to spill over into the human population. SARS-CoV-2 is highly transmissible with a broad tissue tropism that is likely perpetuating the pandemic. However, important questions remain regarding its transmissibility and pathogenesis. In this review, we summarize current SARS-CoV-2 research, with an emphasis on transmission, tissue tropism, viral pathogenesis, and immune antagonism. We further present advances in animal models that are important for understanding the pathogenesis of SARS-CoV-2, vaccine development, and therapeutic testing. When necessary, comparisons are made from studies with SARS to provide further perspectives on coronavirus infectious disease 2019 (COVID-19), as well as draw inferences for future investigations.

Intestinal permeability changes with bacterial translocation as key events modulating systemic host immune response to SARS-CoV-2: A working hypothesis

The microbiota-gut-liver-lung axis plays a bidirectional role in the pathophysiology of a number of infectious diseases. During the course of severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and 2 (SARS-CoV-2) infection, this pathway is unbalanced due to intestinal involvement and systemic inflammatory response. Moreover, there is convincing preliminary evidence linking microbiota-gut-liver axis perturbations, proinflammatory status, and endothelial damage in noncommunicable preventable diseases with coronavirus disease 2019 (Covid-19) severity. Intestinal damage due to SARS-CoV-2 infection, systemic inflammation-induced dysfunction, and IL-6-mediated diffuse vascular damage may increase intestinal permeability and precipitate bacterial translocation. The systemic release of damage- and pathogen-associated molecular patterns (e.g. lipopolysaccharides) and consequent immune-activation may in turn auto-fuel vicious cycles of systemic inflammation and tissue damage. Thus, intestinal bacterial translocation may play an additive/synergistic role in the cytokine release syndrome in Covid-19. This review provides evidence on gut-liver axis involvement in Covid-19 as well as insights into the hypothesis that intestinal endotheliitis and permeability changes with bacterial translocation are key pathophysiologic events modulating systemic inflammatory response. Moreover, it presents an overview of readily applicable measures for the modulation of the gut-liver axis and microbiota in clinical practice.

Clinical Features and Outcomes of ICU Patients with COVID-19 Infection in Tehran, Iran: a Single-Centered Retrospective Cohort Study

BACKGROUND

The clinical characteristics of the novel coronavirus disease (COVID-19) were diverse and unspecific. Here, we identified the associated factors with surviving of COVID-19 ICU patients based on the clinical characteristics of patients admitted to one of the Corona Centre Hospitals of Iran.

MATERIALS AND METHODS

This cohort study was performed retrospectively from February to June 2020 on 133 COVID-19 patients admitted to 4 intensive care units of Masih Daneshvari Hospital in Tehran, Iran. Demographic, medical, clinical manifestation at admission, laboratory parameters and outcome data were obtained from medical records. Also the SOFA and APACHE II scores were calculated. All data were analyzed using SPSS (version 23, IBM Corp.) software.

RESULTS

The median (IQR) age of the patients was 62.0 (54.0-72.0) years in total. RT-PCR of throat swab SARS-CoV-2 in 80 patients (60.2%) was positive. Total mortality rate was 57.9 percent (77 patients). Dyspnea, hypertension and chronic pulmonary diseases were significantly common in non-survivors than survivors (p<0.05). Both SOFA and APACHE II scores were significantly higher in the non-survivors (p<0.05). Also other significant differences were observed in other parameters of the study.

CONCLUSION

The mortality rate of COVID-19 patients admitted to ICU is generally high. Dyspnea as initial presentation and comorbidity, especially hypertension and pulmonary diseases, may be associated with higher risk of severe disease and consequent mortality rate. Also, higher SOFA and APACHE II scores could indicate higher mortality in patients admitted to ICU.

SARS-CoV-2 pathophysiology and its clinical implications: An integrative overview of the pharmacotherapeutic management of COVID-19

Common manifestations of COVID-19 are respiratory and can extend from mild symptoms to severe acute respiratory distress. The severity of the illness can also extend from mild disease to life-threatening acute respiratory distress syndrome (ARDS). SARS-CoV-2 infection can also affect the gastrointestinal tract, liver and pancreatic functions, leading to gastrointestinal symptoms. Moreover, SARS-CoV-2 can cause central and peripheral neurological manifestations, affect the cardiovascular system and promote renal dysfunction. Epidemiological data have indicated that cancer patients are at a higher risk of contracting the SARS-CoV-2 virus. Considering the multitude of clinical symptoms of COVID-19, the objective of the present review was to summarize their pathophysiology in previously healthy patients, as well as in those with comorbidities. The present review summarizes the current, though admittedly fluid knowledge on the pathophysiology and symptoms of COVID-19 infection. Although unclear issues still remain, the present study contributes to a more complete understanding of the disease, and may drive the direction of new research. The recognition of the severity of the clinical symptoms of COVID-19 is crucial for the specific therapeutic management of affected patients.

Sewage surveillance for the presence of SARS-CoV-2 genome as a useful wastewater based epidemiology (WBE) tracking tool in India

The infection with SARS-CoV-2 is reported to be accompanied by the shedding of the virus in fecal samples of infected patients. Earlier reports have suggested that COVID-19 agents can be present in the sewage samples and thus it can be a good indication of the pandemic extent in a community. However, no such studies have been reported in the Indian context. Hence, it becomes absolutely necessary to detect the presence of the SARS-CoV-2 in the wastewater samples from wastewater treatment plants (WWTPs) serving different localities of Jaipur city. Samples from different WWTPs and hospital wastewater samples were collected and wastewater based epidemiology (WBE) studies were carried out using the RT-PCR to confirm the presence of different COVID-19 target genes namely S gene, E gene, ORF1ab gene, RdRp gene and N gene. The results revealed that the untreated wastewater samples showed the presence of SARS-CoV-2 viral genome, which was correlated with the increased number of COVID-19 positive patients from the concerned areas, as reported in the publically available health data. This is the first study that investigated the presence of SARS-CoV-2 viral genome in wastewater, at higher ambient temperature (45 °C), further validating WBE as potential tool in predicting and mitigating outbreaks.

Gastrointestinal symptoms associated with COVID-19: impact on the gut microbiome

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the greatest worldwide pandemic since the 1918 flu. The consequences of the coronavirus disease 2019 (COVID-19) are devastating and represent the current major public health issue across the globe. At the onset, SARS-CoV-2 primarily attacks the respiratory system as it represents the main point of entry in the host, but it also can affect multiple organs. Although most of the patients do not present symptoms or are mildly symptomatic, some people infected with SARS-CoV-2 that experience more severe multiorgan dysfunction. The severity of COVID-19 is typically combined with a set of comorbidities such as hypertension, diabetes, obesity, and/or advanced age that seriously exacerbates the consequences of the infection. Also, SARS-CoV-2 can cause gastrointestinal symptoms, such as vomiting, diarrhea, or abdominal pain during the early phases of the disease. Intestinal dysfunction induces changes in intestinal microbes, and an increase in inflammatory cytokines. Thus, diagnosing gastrointestinal symptoms that precede respiratory problems during COVID-19 may be necessary for improved early detection and treatment. Uncovering the composition of the microbiota and its metabolic products in the context of COVID-19 can help determine novel biomarkers of the disease and help identify new therapeutic targets. Elucidating changes to the microbiome as reliable biomarkers in the context of COVID-19 represent an overlooked piece of the disease puzzle and requires further investigation.

Estimation of the potential spread risk of COVID-19: Occurrence assessment along the Yangtze, Han, and Fu River basins in Hubei, China

Given that the novel coronavirus was detected in stool and urine from diagnosed patients, the potential risk of its transmission through the water environment might not be ignored. In the current study, to investigate the spread possibility of COVID-19 via the environmental media, three typical rivers (Yangtze, Han, and Fu River) and watershed cities in Hubei province of China were selected, and a more comprehensive risk assessment analysis method was built with a risk index proposed. Results showed that the risk index in the Yangtze River Basin is about 10^-12, compared to 10^-10 and 10^-8 in the Han and Fu River Basins, and the risk index is gradually reduced from Wuhan city to the surrounding cities. The safety radius and safety time period for the Yangtze, Han, and Fu River are 8 km/14 h, 20 km/30 h and 36 km/36 h, respectively. The linear relationship between the risk potential calculated by the QMRA model and the multiple linear regression proved that the built index model is statistically significant. By comparing the theoretical removal rates for the novel coronavirus, our study proposed an effective method to estimate the potential spread risk of COVID-19 in the typical river basins.

Clinical Characteristics, Diagnosis, and Treatment of Major Coronavirus Outbreaks

Human coronavirus infections have been known to cause mild respiratory illness. It changed in the last two decades as three global outbreaks by coronaviruses led to significant mortality and morbidity. SARS CoV-1 led to the first epidemic of the twenty first century due to coronavirus. SARS COV-1 infection had a broad array of symptoms with respiratory and gastrointestinal as most frequent. The last known case was reported in 2004. Middle East respiratory syndrome coronavirus (MERS-CoV) led to the second outbreak in 2012, and case fatality was much higher than SARS. MERS-CoV has a wide array of clinical presentations from mild, moderate to severe, and some patients end up with acute respiratory distress syndrome (ARDS). The third and recent outbreak by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started in December 2019, which lead to a global pandemic. Patients with SARS-CoV2 infection can be asymptomatic or have a range of symptoms with fever, cough, and shortness of breath being most common. Reverse transcriptase-Polymerase chain reaction (RT-PCR) is a diagnostic test of choice for SARS CoV-1, MERS-CoV, and SARS CoV-2 infections. This review aims to discuss epidemiological, clinical features, diagnosis, and management of human coronaviruses with a focus on SARS CoV-1, MERS-CoV, and SARS CoV-2.

Gastrointestinal involvement attenuates COVID-19 severity and mortality

Given that gastrointestinal (GI) symptoms are a prominent extrapulmonary manifestation of coronavirus disease 2019 (COVID-19), we investigated intestinal infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its effect on disease pathogenesis. SARS-CoV-2 was detected in small intestinal enterocytes by immunofluorescence staining or electron microscopy, in 13 of 15 patients studied. High dimensional analyses of GI tissues revealed low levels of inflammation in general, including active downregulation of key inflammatory genes such as IFNG, CXCL8, CXCL2 and IL1B and reduced frequencies of proinflammatory dendritic cell subsets. To evaluate the clinical significance of these findings, examination of two large, independent cohorts of hospitalized patients in the United States and Europe revealed a significant reduction in disease severity and mortality that was independent of gender, age, and examined co-morbid illnesses. The observed mortality reduction in COVID-19 patients with GI symptoms was associated with reduced levels of key inflammatory proteins including IL-6, CXCL8, IL-17A and CCL28 in circulation but was not associated with significant differences in nasopharyngeal viral loads. These data draw attention to organ-level heterogeneity in disease pathogenesis and highlight the role of the GI tract in attenuating SARS-CoV-2-associated inflammation with related mortality benefit.

ONE SENTENCE SUMMARY

Intestinal infection with SARS-CoV-2 is associated with a mild inflammatory response and improved clinical outcomes.

Pathogenesis-directed therapy of 2019 novel coronavirus disease

The 2019 novel coronavirus disease (COVID-19) now is considered a global public health emergency. One of the unprecedented challenges is defining the optimal therapy for those patients with severe pneumonia and systemic manifestations of COVID-19. The optimal therapy should be largely based on the pathogenesis of infections caused by this novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the onset of COVID-19, there have been many prepublications and publications reviewing the therapy of COVID-19 as well as many prepublications and publications reviewing the pathogenesis of SARS-CoV-2. However, there have been no comprehensive reviews that link COVID-19 therapies to the pathogenic mechanisms of SARS-CoV-2. To link COVID-19 therapies to pathogenic mechanisms of SARS-CoV-2, we performed a comprehensive search through MEDLINE, PubMed, medRxiv, EMBASE, Scopus, Google Scholar, and Web of Science using the following keywords: COVID-19, SARS-CoV-2, novel 2019 coronavirus, pathology, pathologic, pathogenesis, pathophysiology, coronavirus pneumonia, coronavirus infection, coronavirus pulmonary infection, coronavirus cardiovascular infection, coronavirus gastroenteritis, coronavirus autopsy findings, viral sepsis, endotheliitis, thrombosis, coagulation abnormalities, immunology, humeral immunity, cellular immunity, inflammation, cytokine storm, superantigen, therapy, treatment, therapeutics, immune-based therapeutics, antiviral agents, respiratory therapy, oxygen therapy, anticoagulation therapy, adjuvant therapy, and preventative therapy. Opinions expressed in this review also are based on personal experience as clinicians, authors, peer reviewers, and editors. This narrative review linking COVID-19 therapies with pathogenic mechanisms of SARS-CoV-2 has resulted in six major therapeutic goals for COVID-19 therapy based on the pathogenic mechanisms of SARS-CoV-2. These goals are listed below: 1. The first goal is identifying COVID-19 patients that require both testing and therapy. This is best accomplished with a COVID-19 molecular test from symptomatic patients as well as determining the oxygen saturation in such patients with a pulse oximeter. Whether a symptomatic respiratory illness is COVID-19, influenza, or another respiratory pathogen, an oxygen saturation less than 90% means that the patient requires medical assistance. 2. The second goal is to correct the hypoxia. This goal generally requires hospitalization for oxygen therapy; other respiratory-directed therapies such as prone positioning or mechanical ventilation are often used in the attempt to correct hypoxemia due to COVID-19. 3. The third goal is to reduce the viral load of SARS-CoV-2. Ideally, there would be an oral antiviral agent available such as seen with the use of oseltamivir phosphate for influenza. This oral antiviral agent should be taken early in the course of SARS-CoV-2 infection. Such an oral agent is not available yet. Currently, two options are available for reducing the viral load of SARS-CoV-2. These are post-Covid-19 plasma with a high neutralizing antibody titer against SARS-CoV-2 or intravenous remdesivir; both options require hospitalization. 4. The fourth goal is to identify and address the hyperinflammation phase often seen in hospitalized COVID-19 patients. Currently, fever with an elevated C-reactive protein is useful for diagnosing this hyperinflammation syndrome. Low-dose dexamethasone therapy currently is the best therapeutic approach. 5. The fifth goal is to identify and address the hypercoagulability phase seen in many hospitalized COVID-19 patients. Patients who would benefit from anticoagulation therapy can be identified by a marked increase in d-dimer and prothrombin time with a decrease in fibrinogen. To correct this disseminated intravascular coagulation-like phase, anticoagulation therapy with low molecular weight heparin is preferred. Anticoagulation therapy with unfractionated heparin is preferred in COVID-19 patients with acute kidney injuries. 6. The last goal is prophylaxis for persons who are not yet infected. Potential supplements include vitamin D and zinc. Although the data for such supplements is not extremely strong, it can be argued that almost 50% of the population worldwide has a vitamin D deficiency. Correcting this deficiency would be beneficial regardless of any impact of COVID-19. Similarly, zinc is an important supplement that is important in one's diet regardless of any effect on SARS-CoV-2. As emerging therapies are found to be more effective against the SARS-CoV-2 pathogenic mechanisms identified, they can be substituted for those therapies presented in this review.

COVID-19 Pandemic: Epidemiology, Etiology, Conventional and Non-Conventional Therapies

Coronavirus disease 2019 (COVID-19), which reported in an outbreak in 2019 in Wuhan, Hubei province, China, is caused by the SARS-CoV-2 virus. The virus belongs to the beta-coronavirus class, along with the Middle East Respiratory Syndrome coronavirus and Severe Acute Respiratory Syndrome coronavirus. Interestingly, the virus binds with angiotensin-converting enzyme-2 found in host cells, through the spike (S) protein that exists on its surface. This binding causes the entry of the virus into cells of the host organism. The actual mechanism used by the COVID-19 virus to induce disease is still speculative. A total of 44,322,504 cases, a 1,173,189 death toll and 32,486,703 recovery cases have been reported in 217 countries globally as of 28 October 2020. Symptoms from the infection of the virus include chest pain, fever, fatigue, nausea, and others. Acute respiratory stress syndrome, arrhythmia, and shock are some of the chronic manifestations recorded in severe COVID-19. Transmission is majorly by individual-to-individual through coughing, sneezing, etc. The lack of knowledge regarding the mechanism of and immune response to the virus has posed a challenge in the development of a novel drug and vaccine. Currently, treatment of the disease involves the use of anti-viral medications such as lopinavir, remdesivir, and other drugs. These drugs show some efficacy in the management of COVID-19. Studies are still on-going for the development of an ideal and novel drug for treatment. In terms of natural product intervention, Traditional Chinese Medicines (TCM) have been employed to alleviate the clinical manifestation and severity of the disease and have shown some efficacy. This review presents an updated detailed overview of COVID-19 and the virus, concerning its structure, epidemiology, symptoms and transmission, immune responses, and current interventions, and highlights the potential of TCM. It is anticipated that this review will further add to the understanding of COVID-19 and the virus, hence opening new research perspectives.

Impact of Gastrointestinal Symptoms in COVID-19: a Molecular Approach

The pandemic of novel coronavirus disease (COVID-19) caused by the Severe Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) creates an immense menace to public health worldwide. Currently, the World Health Organization (WHO) has recognized the novel coronavirus as the main cause of global pandemic. Patients infected with this virus generally show fever, nausea, and respiratory illness, while some patients also manifest gastrointestinal symptoms such as abdominal pain, vomiting, and diarrhea. Traces of SARS-CoV-2 RNA have been found in gastrointestinal cells. Further angiotensin converting enzyme 2 (ACE2) the known receptor for the virus is extensively expressed in these cells. This implies that gastrointestinal tract can be infected and can also present them as a replication site for SARS-CoV-2, but since this infection may lead to multiple organ failure, therefore identification of another receptor is a plausible choice. This review aims to provide comprehensive information about probable receptors such as sialic acid and CD147 which may facilitate the virus entry. Several potential targets are mentioned which can be used as a therapeutic approach for COVID-19 and associated GI disorders. The gut microbiomes are responsible for high levels of interferon-gamma which causes hyper-inflammation and exacerbates the severity of the disease. Briefly, this article highlights the gut microbiome’s relation and provides potential diagnostic approaches like RDT and LC-MS for sensitive and specific identification of viral proteins. Altogether, this article reviews epidemiology, probable receptors and put forward the tentative ideas of the therapeutic targets and diagnostic methods for COVID-19 with gastrointestinal aspect of disease.

[Human coronaviruses]

Four coronaviruses cause frequent and most often mild respiratory infections in humans: HCoV-OC43, HCoV-229E, HCoV-NL63 and HCoV-HKU 1. In addition to these endemic human coronaviruses, three new coronaviruses of zoonotic origin have emerged in the human population over the past 20 years. SARS-CoV (-1) appeared in 2003, MERS-CoV appeared in 2012, and SARS-CoV-2 appeared in 20l9. These three coronaviruses are the causative agents of a severe respiratory syndrome. The epidemic of the severe acute respiratory syndrome (SARS) due to SARS-CoV-l affected approximately 8,000 individuals and caused approximately 800 deaths but was brought under control within a few months. MERS-CoV has caused more than 2,500 cases since 20l2 with a mortality of around 35 %. SARS-CoV-2 is currently responsible for a major pandemic with significant mortality in the elderly or in patients with underlying diseases.

Frontier review on the propensity and repercussion of SARS-CoV-2 migration to aquatic environment

Increased concern has recently emerged pertaining to the occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aquatic environment during the current coronavirus disease 2019 (COVID-19) pandemic. While infectious SARS-CoV-2 has yet to be identified in the aquatic environment, the virus potentially enters the wastewater stream from patient excretions and a precautionary approach dictates evaluating transmission pathways to ensure public health and safety. Although enveloped viruses have presumed low persistence in water and are generally susceptible to inactivation by environmental stressors, previously identified enveloped viruses persist in the aqueous environment from days to several weeks. Our analysis suggests that not only the surface water, but also groundwater, represent SARS-CoV-2 control points through possible leaching and infiltrations of effluents from health care facilities, sewage, and drainage water. Most fecally transmitted viruses are highly persistent in the aquatic environment, and therefore, the persistence of SARS-CoV-2 in water is essential to inform its fate in water, wastewater and groundwater and subsequent human exposure.

COVID-19 and the liver

The current coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has become a major public health crisis over the past few months. Overall case fatality rates range between 2-6%; however, the rates are higher in the elderly and those with underlying comorbidities like diabetes, hypertension and heart disease. Recent reports showed that about 2-11% of patients with COVID-19 had underlying chronic liver disease. During the previous SARS epidemic, around 60% of patients were reported to develop various degrees of liver damage. In the current pandemic, hepatic dysfunction has been seen in 14-53% of patients with COVID-19, particularly in those with severe disease. Cases of acute liver injury have been reported and are associated with higher mortality. Hepatic involvement in COVID-19 could be related to the direct cytopathic effect of the virus, an uncontrolled immune reaction, sepsis or drug-induced liver injury. The postulated mechanism of viral entry is through the host angiotensin-converting enzyme 2 (ACE2) receptors that are abundantly present in type 2 alveolar cells. Interestingly, ACE2 receptors are expressed in the gastrointestinal tract, vascular endothelium and cholangiocytes of the liver. The effects of COVID-19 on underlying chronic liver disease require detailed evaluation and, with data currently lacking, further research is warranted in this area.

Probing antiviral drugs against SARS-CoV-2 through virus-drug association prediction based on the KATZ method

It is urgent to find an effective antiviral drug against SARS-CoV-2. In this study, 96 virus-drug associations (VDAs) from 12 viruses including SARS-CoV-2 and similar viruses and 78 small molecules are selected. Complete genomic sequence similarity of viruses and chemical structure similarity of drugs are then computed. A KATZ-based VDA prediction method (VDA-KATZ) is developed to infer possible drugs associated with SARS-CoV-2. VDA-KATZ obtained the best AUCs of 0.8803 when the walking length is 2. The predicted top 3 antiviral drugs against SARS-CoV-2 are remdesivir, oseltamivir, and zanamivir. Molecular docking is conducted between the predicted top 10 drugs and the virus spike protein/human ACE2. The results showed that the above 3 chemical agents have higher molecular binding energies with ACE2. For the first time, we found that zidovudine may be effective clues of treatment of COVID-19. We hope that our predicted drugs could help to prevent the spreading of COVID.

Relevance of SARS-CoV-2 related factors ACE2 and TMPRSS2 expressions in gastrointestinal tissue with pathogenesis of digestive symptoms, diabetes-associated mortality, and disease recurrence in COVID-19 patients

COVID-19 is caused by a new strain of coronavirus called SARS-coronavirus-2 (SARS-CoV-2), which is a positive sense single strand RNA virus. In humans, it binds to angiotensin converting enzyme 2 (ACE2) with the help a structural protein on its surface called the S-spike. Further, cleavage of the viral spike protein (S) by the proteases like transmembrane serine protease 2 (TMPRSS2) or Cathepsin L (CTSL) is essential to effectuate host cell membrane fusion and virus infectivity. COVID-19 poses intriguing issues with imperative relevance to clinicians. The pathogenesis of GI symptoms, diabetes-associated mortality, and disease recurrence in COVID-19 are of particular relevance because they cannot be sufficiently explained from the existing knowledge of the viral diseases. Tissue specific variations of SARS-CoV-2 cell entry related receptors expression in healthy individuals can help in understanding the pathophysiological basis the aforementioned collection of symptoms. ACE2 mediated dysregulation of sodium dependent glucose transporter (SGLT1 or SLC5A1) in the intestinal epithelium also links it to the pathogenesis of diabetes mellitus which can be a possible reason for the associated mortality in COVID-19 patients with diabetes. High expression of ACE2 in mucosal cells of the intestine and GB make these organs potential sites for the virus entry and replication. Continued replication of the virus at these ACE2 enriched sites may be a basis for the disease recurrence reported in some, thought to be cured, patients. Based on the human tissue specific distribution of SARS-CoV-2 cell entry factors ACE2 and TMPRSS2 and other supportive evidence from the literature, we hypothesize that SARS-CoV-2 host cell entry receptor-ACE2 based mechanism in GI tissue may be involved in COVID-19 (i) in the pathogenesis of digestive symptoms, (ii) in increased diabetic complications, (iii) in disease recurrence.

SARS-CoV-2 in wastewater: State of the knowledge and research needs

The ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a Public Health Emergency of International Concern, which was officially declared by the World Health Organization. SARS-CoV-2 is a member of the family Coronaviridae that consists of a group of enveloped viruses with single-stranded RNA genome, which cause diseases ranging from common colds to acute respiratory distress syndrome. Although the major transmission routes of SARS-CoV-2 are inhalation of aerosol/droplet and person-to-person contact, currently available evidence indicates that the viral RNA is present in wastewater, suggesting the need to better understand wastewater as potential sources of epidemiological data and human health risks. Here, we review the current knowledge related to the potential of wastewater surveillance to understand the epidemiology of COVID-19, methodologies for the detection and quantification of SARS-CoV-2 in wastewater, and information relevant for human health risk assessment of SARS-CoV-2. There has been growing evidence of gastrointestinal symptoms caused by SARS-CoV-2 infections and the presence of viral RNA not only in feces of infected individuals but also in wastewater. One of the major challenges in SARS-CoV-2 detection/quantification in wastewater samples is the lack of an optimized and standardized protocol. Currently available data are also limited for conducting a quantitative microbial risk assessment (QMRA) for SARS-CoV-2 exposure pathways. However, modeling-based approaches have a potential role to play in reducing the impact of the ongoing COVID-19 outbreak. Furthermore, QMRA parameters obtained from previous studies on relevant respiratory viruses help to inform risk assessments of SARS-CoV-2. Our understanding on the potential role of wastewater in SARS-CoV-2 transmission is largely limited by knowledge gaps in its occurrence, persistence, and removal in wastewater. There is an urgent need for further research to establish methodologies for wastewater surveillance and understand the implications of the presence of SARS-CoV-2 in wastewater.

Coronaviruses and gastrointestinal diseases

The effects of coronaviruses on the respiratory system are of great concern, but their effects on the digestive system receive much less attention. Coronaviruses that infect mammals have shown gastrointestinal pathogenicity and caused symptoms such as diarrhea and vomiting. Available data have shown that human coronaviruses, including the newly emerged SARS-CoV-2, mainly infect the respiratory system and cause symptoms such as cough and fever, while they may generate gastrointestinal symptoms. However, there is little about the relation between coronavirus and digestive system. This review specifically addresses the effects of mammalian and human coronaviruses, including SARS-CoV-2, on the digestive tract, helping to cope with the new virus infection-induced disease, COVID-19.

Systematic review with meta-analysis: SARS-CoV-2 stool testing and the potential for faecal-oral transmission

BACKGROUND

Since the start of the COVID-19 pandemic, there have been many scientific reports regarding gastrointestinal manifestations. Several reports indicate the possibility of viral shedding via faeces and the possibility of faecal-oral transmission.

AIMS

To critically assess the clinical relevance of testing stool samples and anal swabs and provide an overview of the potential faecal-oral transmission of SARS-CoV-2.

METHODS

A systematic literature search with MeSH terms was performed, scrutinising the Embase database, Google scholar, MEDLINE database through PubMed and The Cochrane Library, including articles from December 2019 until July 7 2020. Data were subsequently analysed with descriptive statistics.

RESULTS

Ninety-five studies were included in the qualitative analysis. 934/2149 (43%) patients tested positive for SARS-CoV-2 in stool samples or anal swabs, with positive test results up to 70 days after symptom onset. A meta-analysis executed with studies of at least 10 patients revealed a pooled positive proportion of 51.8% (95% CI 43.8 - 59.7%). Positive faecal samples of 282/443 patients (64%) remained positive for SARS-CoV-2 for a mean of 12.5 days, up to 33 days maximum, after respiratory samples became negative for SARS-CoV-2. Viable SARS-CoV-2 was found in 6/17 (35%) patients in whom this was specifically investigated.

CONCLUSIONS

Viral shedding of SARS-CoV-2 in stool samples occurs in a substantial proportion of patients, making faecal-oral transmission plausible. Furthermore, detection in stool samples or anal swabs can persist long after negative respiratory testing. Therefore, stool sample or anal swab testing should be (re)considered in relation to decisions for isolating or discharging a patient.

SARS-CoV-2 Induces a More Robust Innate Immune Response and Replicates Less Efficiently Than SARS-CoV in the Human Intestines: An Ex Vivo Study With Implications on Pathogenesis of COVID-19

BACKGROUND AND AIMS

Besides prominent respiratory involvement, gastrointestinal manifestations are commonly reported in Coronavirus Disease 2019 (COVID-19) patients. We compared infection of ex vivo human intestinal tissues by SARS-CoV-2 and SARS-CoV with respect to their replication kinetics and immune activation profile.

METHODS

Human intestinal tissues were obtained from patients while undergoing surgical operations at Queen Mary Hospital, Hong Kong. Upon surgical removal, the tissues were immediately processed and infected with SARS-CoV-2 or SARS-CoV. Replication kinetics were determined with immunohistochemistry, qRT-PCR, and plaque assays. Immune activation in the infected intestinal tissues was assessed by detecting the gene expression of interferons and representative pro-inflammatory cytokines and chemokines.

RESULTS

SARS-CoV-2 could infect and productively replicate in the ex vivo human intestinal tissues with release of infectious virus particles, but not in ex vivo human liver and kidney tissues. Importantly, SARS-CoV-2 replicated less efficiently than SARS-CoV, induced less cytopathology in the human intestinal epithelium, and induced a more robust innate immune response including the activation of both type I and type III interferons, than SARS-CoV in human intestinal tissues.

CONCLUSION

Using the ex vivo human intestinal tissues as a physiologically relevant model, our data indicated that SARS-CoV-2 could productively replicate in the human gut and suggested that the gastrointestinal tract might serve as an alternative route of virus dissemination. SARS-CoV-2 replicated less efficiently and induced less cytopathology than SARS-CoV in keeping with the clinical observations reported for COVID-19 and SARS, which might be the result of a more robust immune activation by SARS-CoV-2 than SARS-CoV in the human intestine.

Coronaviruses in wastewater processes: Source, fate and potential risks

The last 17 years have seen three major outbreaks caused by coronaviruses, with the latest outbreak, COVID-19, declared a pandemic by the World Health Organization. The frequency of these outbreaks, their mortality and associated disruption to normal life calls for concerted efforts to understand their occurrence and fate in different environments. There is an increased interest in the occurrence of coronaviruses in wastewater from the perspective of wastewater-based epidemiology. However, there is no comprehensive review of the knowledge on coronavirus occurrence, fate and potential transmission in wastewater. This paper, provides a review of the literature on the occurrence of coronaviruses in wastewater treatment processes. We discuss the presence of viral RNA in feces as a result of diarrhoea caused by gastrointestinal infections. We also reviewed the literature on the presence, survival and potential removal of coronaviruses in common wastewater treatment processes. The detection of infectious viral particles in feces of patients raises questions on the potential risks of infection for people exposed to untreated sewage/wastewater. We, therefore, highlighted the potential risk of infection with coronaviruses for workers in wastewater treatment plants and the public that may be exposed through faulty plumbing or burst sewer networks. The mortalities and morbidities associated with the current COVID-19 pandemic warrants a much more focused research on the role of environments, such as wastewater and surface water, in disease transmission. The current wealth of knowledge on coronaviruses in wastewater based on the reviewed literature is scant and therefore calls for further studies.

Immunology of COVID-19: Mechanisms, clinical outcome, diagnostics, and perspectives-A report of the European Academy of Allergy and Clinical Immunology (EAACI)

With the worldwide spread of the novel severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) resulting in declaration of a pandemic by the World Health Organization (WHO) on March 11, 2020, the SARS‐CoV‐2‐induced coronavirus disease‐19 (COVID‐19) has become one of the main challenges of our times. The high infection rate and the severe disease course led to major safety and social restriction measures worldwide. There is an urgent need of unbiased expert knowledge guiding the development of efficient treatment and prevention strategies. This report summarizes current immunological data on mechanisms associated with the SARS‐CoV‐2 infection and COVID‐19 development and progression to the most severe forms. We characterize the differences between adequate innate and adaptive immune response in mild disease and the deep immune dysfunction in the severe multiorgan disease. The similarities of the human immune response to SARS‐CoV‐2 and the SARS‐CoV and MERS‐CoV are underlined. We also summarize known and potential SARS‐CoV‐2 receptors on epithelial barriers, immune cells, endothelium and clinically involved organs such as lung, gut, kidney, cardiovascular, and neuronal system. Finally, we discuss the known and potential mechanisms underlying the involvement of comorbidities, gender, and age in development of COVID‐19. Consequently, we highlight the knowledge gaps and urgent research requirements to provide a quick roadmap for ongoing and needed COVID‐19 studies.

Case report of familial COVID-19 cluster associated with High prevalence of anosmia, ageusia, and gastrointestinal symptoms

BACKGROUND

Patients with COVID-19 most commonly report respiratory symptoms, with a minority reporting gastrointestinal (GI) symptoms in currently available reports. Additionally, little is known about the symptoms of anosmia/hyposmia, ageusia, and dysgeusia anecdotally seen in COVID-19 patients, which may potentially be considered both GI and sensory/neurological manifestations of infection. We hope to clarify the prevalence of these symptoms and patterns of transmission within a family cluster.

CASE PRESENTATION

We interviewed 7 patients via oral inquiries and a questionnaire, collecting data on subject symptoms and their durations. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to confirm 2 of these cases. We report a familial cluster of 5 presumed and 2 confirmed COVID-19 cases, all of whom reported one or more GI symptoms and 5 of whom reported sensory symptoms of anosmia/hyposmia, ageusia/hypogeusia, and/or dysgeusia.

CONCLUSIONS

This frequency of GI symptoms is high relative to currently available epidemiological reports, which also infrequently report on sensory symptoms. COVID-19 exhibits wide variation in duration, severity, and progression of symptoms, even within a familial cluster.

Laboratory diagnosis of novel corona virus (2019-nCoV)-present and the future

Background

In December 2019 a novel coronavirus SARS-CoV-2 emerged in the Hunan seafood market in Wuhan, China, and soon became a global health problem. Since its outbreak, SARS-CoV-2 has had a major impact on clinical diagnostic laboratories. The scientific community has quickly risen to the occasion and reports of new developments have arrived at an unprecedented scale. At present, there is a growing list of over 400 SARC-CoV-2 diagnostic tests either in development or approved for clinical use. This presentation reviews the current laboratory methods available for testing COVID- 19 in microbiology laboratories and also provides an insight into the future diagnostics approaches.

Methods

Proper respiratory specimen collected at the appropriate time and from the right anatomical site is critical in the accurate and timely diagnosis of SARSCoV2. While oropharyngeal and nasopharyngeal swabs are recommended for the detection of early infection, other lower respiratory tract specimens like the sputum and bronchoalveolar lavage are used for late detection and monitoring of patients with severe COVID-19 pneumonia.

Results and Conclusion

Real-time RT-PCR based molecular assay remains the test of choice for the etiological diagnosis of SARS-CoV-2 while serological tests are being introduced as supplementary tools. Finally, there is an urgent need for scaling up the diagnostic capacity by the introduction of reliable and accurate point-of-care tests which will assist in effective control of this outbreak. These assays can be used in the local hospitals and clinics bearing the burden of identifying and treating patients.

•

At present, there is a growing list of over 400 SARC-CoV-2 diagnostic tests either in development or approved for clinical use.

•

Real-time RT-PCR based molecular assay remains the test of choice for the etiological diagnosis of SARS-CoV-2.

•

Oropharyngeal and nasopharyngeal swabs are recommended for the detection of early infection.

•

Lower respiratory tract specimens can be used for late detection and monitoring of patients with severe COVID-19 pneumonia.

•

There is an urgent need for scaling up the diagnostic capacity by the introduction of reliable POC tests.

SARS-CoV-2: A comprehensive review from pathogenicity of the virus to clinical consequences

Nowadays, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which caused novel coronavirus disease (COVID-19) pandemic, is the worldwide challenge. The virus is highly contagious, and clinical consequences were very divers. It is estimated that if no effective action is taken, COVID-19 could plague 90% of the world's population and kill over 40 million people. So, it is essential to understand the virus pathogenicity and follow the preventive methods to control the high morbidity and mortality rates. Meanwhile our current knowledge of COVID-19 is still limited, despite hard efforts of scientists and clinicians during last few months. In this review article, we have collected the latest data about characteristics, pathogenesis, clinical manifestations, and diagnostic methods of SARS-CoV-2.

Potential contribution of beneficial microbes to face the COVID-19 pandemic

The year 2020 will be remembered by a never before seen, at least by our generation, global pandemic of COVID-19. While a desperate search for effective vaccines or drug therapies is on the run, nutritional strategies to promote immunity against SARS-CoV-2, are being discussed. Certain fermented foods and probiotics may deliver viable microbes with the potential to promote gut immunity. Prebiotics, on their side, may enhance gut immunity by selectively stimulating certain resident microbes in the gut. Different levels of evidence support the use of fermented foods, probiotics and prebiotics to promote gut and lungs immunity. Without being a promise of efficacy against COVID-19, incorporating them into the diet may help to low down gut inflammation and to enhance mucosal immunity, to possibly better face the infection by contributing to diminishing the severity or the duration of infection episodes.

Alcohol-based hand sanitisers as first line of defence against SARS-CoV-2: a review of biology, chemistry and formulations

The pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has emerged as a serious global public health issue. Since the start of the outbreak, the importance of hand-hygiene and respiratory protection to prevent the spread of the virus has been the prime focus for infection control. Health regulatory organisations have produced guidelines for the formulation of hand sanitisers to the manufacturing industries. This review summarises the studies on alcohol-based hand sanitisers and their disinfectant activity against SARS-CoV-2 and related viruses. The literature shows that the type and concentration of alcohol, formulation and nature of product, presence of excipients, applied volume, contact time and viral contamination load are critical factors that determine the effectiveness of hand sanitisers.

Gastrointestinal involvement of COVID-19 and potential faecal transmission of SARS-CoV-2

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was found initially in Wuhan, China in early December 2019. The pandemic has spread to 216 countries and regions, infecting more than 23310 000 people and causing over 800 000 deaths globally by Aug. 24, 2020, according to World Health Organization (https://www.who.int/emergencies/diseases/ novel-coronavirus-2019). Fever, cough, and dyspnea are the three common symptoms of the condition, whereas the conventional transmission route for SARS-CoV-2 is through droplets entering the respiratory tract. To date, infection control measures for COVID-19 have been focusing on the involvement of the respiratory system. However, ignoring potential faecal transmission and the gastrointestinal involvement of SARS-CoV-2 may result in mistakes in attempts to control the pandemic.

COVID-19 and the Global Impact on Colorectal Practice and Surgery

BACKGROUND

The novel severe acute respiratory syndrome coronavirus 2 virus that emerged in December 2019 causing coronavirus disease 2019 (COVID-19) has led to the sudden national reorganization of health care systems and changes in the delivery of health care globally. The purpose of our study was to use a survey to assess the global effects of COVID-19 on colorectal practice and surgery.

MATERIALS AND METHODS

A panel of International Society of University Colon and Rectal Surgeons (ISUCRS) selected 22 questions, which were included in the questionnaire. The questionnaire was distributed electronically to ISUCRS fellows and other surgeons included in the ISUCRS database and was advertised on social media sites. The questionnaire remained open from April 16 to 28, 2020.

RESULTS

A total of 287 surgeons completed the survey. Of the 287 respondents, 90% were colorectal specialists or general surgeons with an interest in colorectal disease. COVID-19 had affected the practice of 96% of the surgeons, and 52% were now using telemedicine. Also, 66% reported that elective colorectal cancer surgery could proceed but with perioperative precautions. Of the 287 respondents, 19.5% reported that the use of personal protective equipment was the most important perioperative precaution. However, personal protective equipment was only provided by 9.1% of hospitals. In addition, 64% of surgeons were offering minimally invasive surgery. However, 44% reported that enough information was not available regarding the safety of the loss of intra-abdominal carbon dioxide gas during the COVID-19 pandemic. Finally, 61% of the surgeons were prepared to defer elective colorectal cancer surgery, with 29% willing to defer for ≤ 8 weeks.

CONCLUSION

The results from our survey have demonstrated that, globally, COVID-19 has affected the ability of colorectal surgeons to offer care to their patients. We have also discussed suggestions for various practical adaptation strategies for use during the recovery period.

ACE2 imbalance as a key player for the poor outcomes in COVID-19 patients with age-related comorbidities - Role of gut microbiota dysbiosis

•

COVID-19 patients with pre-existing age-related comorbidities have poor outcomes.

•

Gut microbiota dysbiosis is associated with ageing and age-related diseases.

•

Viral-mediated ACE2 shedding favors poor outcomes by RAS-dependent mechanisms.

•

Viral-mediated ACE2 shedding favors poor outcomes by RAS-independent gut dysbiosis.

•

Potential of ACE2 and gut microbiota-based therapeutic opportunities for COVID-19.

Coronavirus disease 19 (COVID-19) is a pandemic condition caused by the new coronavirus SARS-CoV-2. The typical symptoms are fever, cough, shortness of breath, evolving to a clinical picture of pneumonia and, ultimately, death. Nausea and diarrhea are equally frequent, suggesting viral infection or transmission via the gastrointestinal-enteric system. SARS-CoV-2 infects human cells by using angiotensin converting enzyme 2 (ACE2) as a receptor, which is cleaved by transmembrane proteases during host cells infection, thus reducing its activities. ACE2 is a relevant player in the renin-angiotensin system (RAS), counterbalancing the deleterious effects of angiotensin II. Furthermore, intestinal ACE2 functions as a chaperone for the aminoacid transporter B⁰AT1. It has been suggested that B⁰AT1/ACE2 complex in the intestinal epithelium regulates gut microbiota (GM) composition and function, with important repercussions on local and systemic immune responses against pathogenic agents, namely virus. Notably, productive infection of SARS-CoV-2 in ACE2⁺ mature human enterocytes and patients’ GM dysbiosis was recently demonstrated. This review outlines the evidence linking abnormal ACE2 functions with the poor outcomes (higher disease severity and mortality rate) in COVID-19 patients with pre-existing age-related comorbidities and addresses a possible role for GM dysbiosis. The article culminates with the therapeutics opportunities based on these pathways.

Spillover of SARS-CoV-2 into novel wild hosts in North America: A conceptual model for perpetuation of the pathogen

There is evidence that the current outbreak of the novel coronavirus SARS-CoV-2, which causes COVID-19, is of animal origin. As with a number of zoonotic pathogens, there is a risk of spillover into novel hosts. Here, we propose a hypothesized conceptual model that illustrates the mechanism whereby the SARS-CoV-2 could spillover from infected humans to naive wildlife hosts in North America. This proposed model is premised on transmission of SARS-CoV-2 from human feces through municipal waste water treatment plants into the natural aquatic environment where potential wildlife hosts become infected. We use the existing literature on human coronaviruses, including SARS CoV, to support the potential pathways and mechanisms in the conceptual model. Although we focus on North America, our conceptual model could apply to other parts of the globe as well.

COVID-19: Transmission, prevention, and potential therapeutic opportunities

The novel coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global challenge. Despite intense research efforts worldwide, an effective vaccine and viable treatment options have eluded investigators. Therefore, infection prevention, early viral detection and identification of successful treatment protocols provide the best approach in controlling disease spread. In this review, current therapeutic options, preventive methods and transmission routes of COVID-19 are discussed.

Water matrices as potential source of SARS-CoV-2 transmission - An overview from environmental perspective

Evidently, the emergence of novel coronavirus disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has rapidly blowout across the world. Since, the presence of coronaviruses, including SARS-CoV-2 in the fecal specimens and anal swabs of some infected patients, has raised emerging concern with the likelihood of fecal-based spread must be inspected and clarified. Therefore, herein, an effort has been made to spotlight the current scenarios and possible solutions to better understand the risks associated with the wastewater matrices as a potential source of SARS-CoV-2 transmission in the environment. The information reviewed here constitutes a paramount intellectual basis to sustenance ongoing research to tackle the SARS-CoV-2 issue. Thus, this overview indicates the most accessible frontiers related to the detection, quantification, and possible transmission of SARS-CoV-2 in the environment through water routes. The regulatory authorities and policymakers must assure the society via dissemination of evidence-based guidelines that the water matrices, including groundwater and drinking water resources are safe. Finally, we have identified and enlisted a number of pressing questions concerning the ongoing SARS-CoV-2 transmission or COVID-19 emergence issue that must be carefully answered to put further and deeper insight into SARS-CoV-2/COVID-19 in future studies.

COVID-19 extrapulmonary illness - special gastrointestinal and hepatic considerations

Coronaviruses have caused three global outbreaks in the last 20 years, which include Severe Acute Respiratory Syndrome (SARS) caused by SARS-CoV (SARS-CoV-1), Middle East Respiratory Syndrome (MERS) by MERS-CoV and Coronavirus Disease-2019 (COVID-19) due to SARS-CoV-2. These outbreaks share many similarities, including clinical presentation, transmission, and management. Although respiratory manifestations are responsible for most of the morbidity and mortality in these conditions, extra-pulmonary manifestations such as gastrointestinal symptoms are also increasingly recognized as important symptoms. Important gastrointestinal symptoms include nausea, vomiting, anorexia, diarrhea, and abdominal pain. Hepatic manifestations such as abnormal aminotransferases are also noted in these patients. Early identification of GI symptoms is crucial as some patients can present only with GI manifestations in the absence of pulmonary symptoms. Furthermore, patients with diarrhea have tested positive for viral RNA in the stool. This has been reported even after the resolution of respiratory symptoms and can extend up to many days from the onset of symptoms. Because of this phenomenon, there is a theoretical risk of fecal-oral transmission and the potential spread of the disease. Though GI symptoms are frequently observed, understanding the pathogenesis of these symptoms is crucial, as it can not only of public health importance but could also identify infected patients early in the spread. Understanding the different GI and hepatic manifestations with underlying mechanisms of symptoms can assist in the therapeutic management of these patients. In this article, we summarize various GI and hepatic manifestations with their prevalence, underlying pathophysiology with emphasis on stool positivity.

The Thrilling Journey of SARS-CoV-2 into the Intestine: From Pathogenesis to Future Clinical Implications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has a direct impact on the gastrointestinal system, as up to 50% of fecal samples from coronavirus disease 2019 (COVID-19) patients contain detectable viral RNA despite a negative rhino-pharyngeal swab. This finding, together with an intestinal expression of angiotensin conversion enzyme 2 protein, suggests a possible fecal-oral transmission for SARS-CoV-2. Furthermore, gastrointestinal (GI) symptoms are common in COVID-19 patients including watery diarrhea, vomiting-particularly in children-nausea, and abdominal pain. Pathogenesis of SARS-CoV-2 infection presents significant similarities to those of some immune-mediated diseases, such as inflammatory bowel diseases or rheumatoid arthritis, leading to the hypothesis that targeted therapies used for the treatment of immune-mediated disease could be effective to treat (and possibly prevent) the main complications of COVID-19. In this review, we synthesize the present and future impact of SARS-CoV-2 infection on the gastrointestinal system and on gastroenterology practice, hypothesizing a potential role of the "gut-lung axis" and perhaps of the gut and lung microbiota into the interindividual differential susceptibility to COVID-19 19 disease. Finally, we speculate on the reorganization of outpatient gastroenterology services, which need to consider, among other factors, the major psychological impact of strict lockdown measures on the whole population.

Anal swab as a potentially optimal specimen for SARS-CoV-2 detection to evaluate hospital discharge of COVID-19 patients

Since December 2019, an outbreak of SARS coronavirus 2 (SARS-CoV-2) began in Wuhan, and has rapidly spread worldwide. Previously, discharged patients with coronavirus disease 2019 (COVID-19) patients met the criteria of China's pneumonia diagnosis and treatment program of novel coronavirus infection (trial version 7) for cure of viral infection. Nevertheless, positive detection of SARS-CoV-2 has been found again in several cured COVID-19 patients, leading to conflicts with current criteria. Here, we report clinically cured cases with positive results only in anal swabs, and investigate the clinical value of anal swabs for SARS-CoV-2 detection.

The mechanism and treatment of gastrointestinal symptoms in patients with COVID-19

In addition to the typical respiratory response, new coronavirus disease 2019 (COVID-19) is also associated with very common gastrointestinal symptoms. Cases with gastrointestinal symptoms are more likely to be complicated by liver injury and acute respiratory distress syndrome (ARDS). If not treated in time, coma and circulatory failure may ensue. As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects the human body through the combination of angiotensin-converting enzyme 2 (ACE2) in the gastrointestinal tract, the mechanism underlying the gastrointestinal symptoms may involve damage to the intestinal mucosal barrier and promotion of the production of inflammatory factors. Indeed, after cells in the lungs become infected by SARS-CoV-2, effector CD4+ T cells reach the small intestine through the gut-lung axis, causing intestinal immune damage and diarrhea; early extensive use of antibacterial and antiviral drugs can also lead to diarrhea in patients. Thus, treatment options for COVID-19 patients should be promptly adjusted when they have gastrointestinal symptoms. As SARS-CoV-2 has been detected in the feces of COVID-19 patients, future prevention and control efforts must consider the possibility of fecal-oral transmission of the virus.

Safety in digestive endoscopy procedures in the covid era recommendations in progres of the italian society of digestive endoscopy

The new corona virus disease has started in Wuhan - China at the end of 2019 and quickly spread with a pandemic trend across the rest of the world. The scientific community is making an extraordinary effort to study and control the situation, but the results are just partial. Based on the most recent scientific literature and strong statements by the most prestigious international health institutions, the Italian Society of Digestive Endoscopy has drawn up some recommendations about the use of personal protective equipment, the correct way of dressing and undressing of endoscopists and nurses, before and after digestive endoscopy procedures. In addition, some other important indications are given to reduce the risk of contamination of healthcare providers during endoscopic activities, in the setting of a pandemic. Nevertheless, because of the very quick evolution of our knowledge on this issue, these recommendations must be considered as evolving, because they could change in a short time.