Clinical features and virological analysis of a case of Middle East respiratory syndrome coronavirus infection

Occupational Health Hazards Among Veterinarians in Saudi Arabia

Introduction Veterinarians and other professionals who interact with animals on a daily basis encounter an elevated risk of exposure to both known and as-yet-undiscovered microbial agents. Additionally, they are also exposed to physical, chemical, and environmental hazards. Enhancing occupational health and safety in this context carries significant global significance. Methods This study aimed to comprehensively identify and outline the various biological, physical, chemical, and environmental health threats that were encountered by veterinarians in Saudi Arabia. To achieve this, we designed a self-completed questionnaire for 529 participants. The survey encompassed potential occupational hazards such as microbial diseases, injuries resulting from animal bites and scratches, allergies, and environmental risks like sunstroke and dust storms. Results Among the 529 participating veterinarians, 45.9% (243 individuals) reported instances of zoonotic diseases within the past five years. Notably, potential viral agents included Middle East respiratory syndrome coronavirus, avian influenza, and foot-and-mouth disease virus. Bacterial diseases were also frequently documented, with brucellosis (18.7%) and salmonellosis (7.9%) being notable pathogens. Protozoal infections were led by Leishmaniosis, constituting the most commonly detected protozoa (29 /529, 5.5%). Interestingly, 345 (65.2%) of the individuals reported that they have experienced animal bites and scratches. Needle stick injuries were also a common occupational hazard, with an incidence rate of 19.1%. Additionally, chemical exposure was prevalent, particularly to disinfectants (57.5%) and veterinary drugs (23.4%). The study participants also reported their exposure to various environmental hazards, including sunstroke, dust, sandstorms, and heavy rains. Conclusion The findings of this study draw attention to a concerning trend among veterinarians in Saudi Arabia. Their personal health and safety appear to receive inadequate attention, potentially heightening the risk of occupationally related health hazards. These outcomes highlight the need for a reevaluation of safety protocols and infection control practices within the veterinary profession. The implications of this study can potentially inform the development of policies and initiatives aimed at mitigating occupationally related health hazards among veterinarians in Saudi Arabia.

The Protective Efficacy of Single-Dose Nasal Immunization with Cold-Adapted Live-Attenuated MERS-CoV Vaccine against Lethal MERS-CoV Infections in Mice

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe diseases in humans. Camels act as intermediate hosts for MERS-CoV. Currently, no licensed vaccine is available for this virus. We have developed a potential candidate vaccine for MERS-CoV using the cold adaptation method. We cultivated the vaccine in Vero cells at temperatures as low as 22 °C. This live-attenuated vaccine virus showed high attenuation levels in transgenic mice with the MERS-CoV human receptor, dipeptidyl peptidase 4 (DPP4) (K18-hDPP4). The inoculated K18-hDPP4 mice exhibited no clinical signs such as death or body weight loss. Furthermore, no traces of infectious virus were observed when the tissues (nasal turbinate, brain, lung, and kidney) of the K18-hDPP4 mice infected with the cold-adapted vaccine strain were tested. A single intranasal dose of the vaccine administered to the noses of the K18-hDPP4 mice provided complete protection. We did not observe any deaths, body weight loss, or viral detection in the tissues (nasal turbinate, brain, lung, and kidney). Based on these promising results, the developed cold-adapted, attenuated MERS-CoV vaccine strain could be one of the candidates for human and animal vaccines.

Environmental Stability and Transmissibility of Enveloped Viruses at Varied Animate and Inanimate Interfaces

Enveloped viruses have been the leading causative agents of viral epidemics in the past decade, including the ongoing coronavirus disease 2019 outbreak. In epidemics caused by enveloped viruses, direct contact is a common route of infection, while indirect transmissions through the environment also contribute to the spread of the disease, although their significance remains controversial. Bridging the knowledge gap regarding the influence of interfacial interactions on the persistence of enveloped viruses in the environment reveals the transmission mechanisms when the virus undergoes mutations and prevents excessive disinfection during viral epidemics. Herein, from the perspective of the driving force, partition efficiency, and viral survivability at interfaces, we summarize the viral and environmental characteristics that affect the environmental transmission of viruses. We expect to provide insights for virus detection, environmental surveillance, and disinfection to limit the spread of severe acute respiratory syndrome coronavirus 2.

MICaFVi: A Novel Magnetic Immuno-Capture Flow Virometry Nano-Based Diagnostic Tool for Detection of Coronaviruses

COVID-19 has resulted in a pandemic that aggravated the world's healthcare systems, economies, and education, and caused millions of global deaths. Until now, there has been no specific, reliable, and effective treatment to combat the virus and its variants. The current standard tedious PCR-based tests have limitations in terms of sensitivity, specificity, turnaround time, and false negative results. Thus, an alternative, rapid, accurate, and sensitive diagnostic tool that can detect viral particles, without the need for amplification or viral replication, is central to infectious disease surveillance. Here, we report MICaFVi (Magnetic Immuno-Capture Flow Virometry), a novel precise nano-biosensor diagnostic assay for coronavirus detection which combines the MNP-based immuno-capture of viruses for enrichment followed by flow-virometry analysis, enabling the sensitive detection of viral particles and pseudoviruses. As proof of concept, virus-mimicking spike-protein-coated silica particles (VM-SPs) were captured using anti-spike-antibody-conjugated MNPs (AS-MNPs) followed by detection using flow cytometry. Our results showed that MICaFVi can successfully detect viral MERS-CoV/SARS-CoV-2-mimicking particles as well as MERS-CoV pseudoviral particles (MERSpp) with high specificity and sensitivity, where a limit of detection (LOD) of 3.9 µg/mL (20 pmol/mL) was achieved. The proposed method has great potential for designing practical, specific, and point-of-care testing for rapid and sensitive diagnoses of coronavirus and other infectious diseases.

Protein glycosylation in urine as a biomarker of diseases

Human body fluids have become an indispensable resource for clinical research, diagnosis and prognosis. Urine is widely used to discover disease-specific glycoprotein biomarkers because of its recurrently non-invasive collection and disease-indicating properties. While urine is an unstable fluid in that its composition changes with ingested nutrients and further as it is excreted through micturition, urinary proteins are more stable and their abnormal glycosylation is associated with diseases. It is known that aberrant glycosylation can define tumor malignancy and indicate disease initiation and progression. However, a thorough and translational survey of urinary glycosylation in diseases has not been performed. In this article, we evaluate the clinical applications of urine, introduce methods for urine glycosylation analysis, and discuss urine glycoprotein biomarkers. We emphasize the importance of mining urinary glycoproteins and searching for disease-specific glycosylation in various diseases (including cancer, neurodegenerative diseases, diabetes, and viral infections). With advances in mass spectrometry-based glycomics/glycoproteomics/glycopeptidomics, characterization of disease-specific glycosylation will optimistically lead to the discovery of disease-related urinary biomarkers with better sensitivity and specificity in the near future.

Dressing Bacteria With a Hybrid Immunoactive Nanosurface to Elicit Dual Anticancer and Antiviral Immunity

Approaches capable of simultaneously treating cancer and protecting susceptible patients from lethal infections such as coronavirus disease 2019, are highly desirable but prove to be difficult. Here, dressing bacteria with a hybrid immunoactive nanosurface is reported to elicit dual anticancer and antiviral immunity. A combination of a checkpoint blocking antibody and a virus-specific antigen is covalently conjugated to polydopamine nanoparticles, which can be anchored onto bacterial surface, by a one-step in situ polymerization of dopamine under a cell-friendly condition. By virtue of the ability to colonize and penetrate deep tumor tissue, dressed bacteria enable sustained release and expanded exposure of carried immunoactivators to stimulate immune cells. In addition to a carrier role, bacteria are able to further provoke innate immunity due to the native immunogenicity of the pathogen-associated molecular patterns. Immunization with dressed bacteria promotes the maturation, and activation of antigen-presenting cells, which induces robust humoral and cellular immune responses in tumor-bearing mice. As evidenced by efficient production of viral-antigen-specific immunoglobulin G antibody in serum and significantly suppressed tumor growth in different models, dressing bacteria with a hybrid immunoactive nanosurface paves an avenue to prepare next-generation therapeutics for synergistic treatment and prevention.

Combating COVID-19 crisis and exploring heat-based simple solutions

Covid-19 pandemic affected whole of the world taking many lives and impacting the economy and mental health severely. Exit pathways via vaccination though ignited optimism initially but attenuated by the emergence of several new variants which are less sensitive to vaccines. Considering emergency situations, some urgent, simple heat-based solutions for the initial stages of the disease were also proposed at the beginning of pandemic and further elaborated here. Solutions were proposed based on science as follows: exploring results of statistical analyses on the global transmission of COVID-19; observed temperature-dependent behaviours of similar category viruses; temperature-based clinical trial experiments with similar category viruses; successful clinical trial experiments with heat-based intervention for COVID-19 patients; and finally, biological mechanism/response in human bodies to heat-based solution for COVID-19 from medical doctor's perspective. Solutions proposed are practically without side effects, can be even practised in own home and there is no vested interest involved.

The many facets of CD26/dipeptidyl peptidase 4 and its inhibitors in disorders of the CNS - a critical overview

Dipeptidyl peptidase 4 is a serine protease that cleaves X-proline or X-alanine in the penultimate position. Natural substrates of the enzyme are glucagon-like peptide-1, glucagon inhibiting peptide, glucagon, neuropeptide Y, secretin, substance P, pituitary adenylate cyclase-activating polypeptide, endorphins, endomorphins, brain natriuretic peptide, beta-melanocyte stimulating hormone and amyloid peptides as well as some cytokines and chemokines. The enzyme is involved in the maintenance of blood glucose homeostasis and regulation of the immune system. It is expressed in many organs including the brain. DPP4 activity may be effectively depressed by DPP4 inhibitors. Apart from enzyme activity, DPP4 acts as a cell surface (co)receptor, associates with adeosine deaminase, interacts with extracellular matrix, and controls cell migration and differentiation. This review aims at revealing the impact of DPP4 and DPP4 inhibitors for several brain diseases (virus infections affecting the brain, tumours of the CNS, neurological and psychiatric disorders). Special emphasis is given to a possible involvement of DPP4 expressed in the brain.While prominent contributions of extracerebral DPP4 are evident for a majority of diseases discussed herein; a possible role of "brain" DPP4 is restricted to brain cancers and Alzheimer disease. For a number of diseases (Covid-19 infection, type 2 diabetes, Alzheimer disease, vascular dementia, Parkinson disease, Huntington disease, multiple sclerosis, stroke, and epilepsy), use of DPP4 inhibitors has been shown to have a disease-mitigating effect. However, these beneficial effects should mostly be attributed to the depression of "peripheral" DPP4, since currently used DPP4 inhibitors are not able to pass through the intact blood-brain barrier.

Ventilation reconstruction in bathrooms for restraining hazardous plume: Mitigate COVID-19 and beyond

Converging evidence reports that the probability of vertical transmission patterns via shared drainage systems, may be responsible for the huge contactless community outbreak in high-rise buildings. Publications indicate that a faulty bathroom exhaust fan system is ineffective in removing lifted hazardous virus-laden aerosols from the toilet bowl space. Common strategies (boosting ventilation capability and applying disinfection tablets) seem unsustainable and remain to date untested. Using combined simulation and experimental approaches, we compared three ventilation schemes in a family bathroom including the traditional ceiling fan, floor fan, and side-wall fan. We found that the traditional ceiling fan was barely functional whereby aerosol particles were not being adequately removed. Conversely, a side-wall fan could function efficiently and an enhanced ventilation capability can have increased performance whereby nearly 80.9% of the lifted aerosol particles were removed. There exists a common, and easily-overlooked mistake in the layout of the bathroom, exposing occupants to a contactless vertical pathogen aerosol transmission route. Corrections and dissemination are thus imperative for the reconstruction of these types of family bathrooms. Our findings provide evidence for the bathroom and smart ventilation system upgrade, promoting indoor public health and human hygiene.

Investigating the Potential Effects of COVID-19 Pandemic on Intestinal Coccidian Infections

New infectious agents pose a global threat to the healthcare system, and studies are conducted to estimate their health and epidemiological outcomes in the long run. The SARS-CoV-2 virus, which has caused the COVID-19 disease, was formerly assumed to be a respiratory virus; however, it can have serious systemic effects, affecting organs such as the gastrointestinal tract (GIT). Viral RNA was reported in the stool in a subset of patients, indicating another mode of transmission and diagnosis. In COVID-19, prolonged GIT symptoms, especially diarrhea, were associated with reduced diversity and richness of gut microbiota, immunological dysregulation, and delayed viral clearance. Intestinal coccidian parasites are intracellular protozoa that are most typically transmitted to humans by oocysts found in fecally contaminated food and water. Their epidemiological relevance is coupled to opportunistic infections, which cause high morbidity and mortality among immunocompromised individuals. Among immunocompetent people, intestinal coccidia is also involved in acute diarrhea, which is usually self-limiting. Evaluating the available evidence provided an opportunity to carefully consider that; the COVID-19 virus and coccidian protozoan parasites: namely, Cryptosporidium spp., Cyclospora cayetanensis, and Isospora belli, could mutually influence each other from the microbiological, clinical, diagnostic, and elimination aspects. We further systemically highlighted the possible shared pathogenesis mechanisms, transmission routes, clinical manifestations, parasite-driven immune regulation, and intestinal microbiota alteration. Finally, we showed how this might impact developing and developed countries prevention and vaccination strategies. To the best of our knowledge, there is no review that has discussed the reciprocal effect between coccidian parasites and COVID-19 coinfection.

Laboratory and Point-of-Care Testing for COVID-19: A Review of Recent Developments

With the emergence of Coronavirus infection called COVID-19, testing is essential for containment and mitigation purposes. In a pandemic, control is essential to limit the spread of any virus. Initially, contact tracing was not available which ultimately led to the 2020 pandemic. However, with the development of COVID-19 rapid testing, the rate of infections has lessened and has allowed for some return to normalcy. In this review, we discuss the various antibody, antigens, and molecular tests that have been given emergency authorization (EA) from the Food and Drug Administration (FDA). Moreover, we will discuss the various point-of-care tests as well as the specificity and sensitivity that are associated with each testing kit. With appropriate testing, we can be aware of how the virus spreads and how prevalent it remains.

Comparative overview of emerging RNA viruses: Epidemiology, pathogenesis, diagnosis and current treatment

From many decades, emerging infections have threatened humanity. The pandemics caused by different CoVs have already claimed and will continue to claim millions of lives. The SARS, Ebola, MERS epidemics and the most recent emergence of COVID-19 pandemic have threatened populations across borders. Since a highly pathogenic CoV has been evolved into the human population in the twenty-first century known as SARS, scientific advancements and innovative methods to tackle these viruses have increased in order to improve response preparedness towards the unpredictable threat posed by these rapidly emerging pathogens. Recently published review articles on SARS-CoV-2 have mainly focused on its pathogenesis, epidemiology and available treatments. However, in this review, we have done a systematic comparison of all three CoVs i.e., SARS, MERS and SARS-CoV-2 along with Ebola and Zika in terms of their epidemiology, virology, clinical features and current treatment strategies. This review focuses on important emerging RNA viruses starting from Zika, Ebola and the CoVs which include SARS, MERS and SARS-CoV-2. Each of these viruses has been elaborated on the basis of their epidemiology, virulence, transmission and treatment. However, special attention has been given to SARS-CoV-2 and the disease caused by it i.e., COVID-19 due to current havoc caused worldwide. At the end, insights into the current understanding of the lessons learned from previous epidemics to combat emerging CoVs have been described. The travel-related viral spread, the unprecedented nosocomial outbreaks and the high case-fatality rates associated with these highly transmissible and pathogenic viruses highlight the need for new prophylactic and therapeutic actions which include but are not limited to clinical indicators, contact tracing, and laboratory investigations as important factors that need to be taken into account in order to arrive at the final conclusion.

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Recently published review articles on SARS-CoV-2 have mainly focused on its pathogenesis, epidemiology and available treatments.

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The pandemics caused by different CoVs have already claimed and will continue to claim millions of lives.

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This review focuses on important emerging RNA viruses starting from Zika, Ebola and the CoVs which include SARS, MERS and SARS-CoV-2.

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Globally, numerous studies and researchers have recently started fighting this virus.

Assessment of some Physiological Biomarkers in COVID-19 Patients in Thi-Qar, Iraq

It is believed that many biomarkers and factors could be linked to the prognosis of coronavirus disease 2019 (COVID-19). Therefore, this study aimed to evaluate the association of lactate dehydrogenase (LDH), D-Dimer, vitamin D, and ferritin statuses with the prognosis of COVID-19; moreover, it was attempted to investigate its prevalence according to age, employment status, body mass index (BMI), and place of residency in a population sample of hospitalized patients in Thi-Qar, Iraq. This study evaluated 200 COVID-19 patients and 100 controls. The BMI of all individuals was calculated, and such demographic characteristics as age, gender, place of residency, and occupational status were collected from all participants. Blood samples were taken and used to estimate D-Dimer, LDH, vitamin D, ferritin, oxygen, and pulse rate. The mean age of the patients approached the fifth decade, and 72% of the cases were more than 40 years of age. In addition, 60% of the patients were living in the countryside, and 52% of the participants were employed, compared to only 8% of the cases who were students. The BMI of the patients was obtained at 31.44±10.2 kg/m²; accordingly, 47% and 40% of the cases were obese and overweight, respectively, compared to only 12% of the patients who had normal weight (P˂0.05). There were significantly lower vitamin D levels in the patients; however, the concentrations of LDH, serum ferritin, and D-Dimer were significantly higher in the patients, compared to the control group (P˂0.05). Not only age and body weight but also employment status and place of residency maybe also the important risk factors for COVID-19 distribution. LDH, D-dimer, vitamin D, and ferritin statuses could be used as good biomarkers for this disease and its severity.

A systematic review on the occurrence, fate, and remediation of SARS-CoV-2 in wastewater

The COVID-19 has been declared a pandemic by the World Health Organization. Along with impairing the respiratory system, it also affects the gastrointestinal system. By reviewing experiments on the wastewater analysis for the detection of coronavirus, this study explores the fate, persistence, and various remediation strategies for the virus removal from the wastewater. The results indicated that the virus can be detected in the wastewater samples, feces, and sewage, even before the onset of symptoms. Coronavirus can be a potential panzootic disease, as several mammalian species get infected by the deadly virus. The disinfection strategies used earlier for the treatment of wastewater are not sufficient for the removal of viruses from the wastewater. Therefore, concerted efforts should be made to understand their fate, sources, and occurrence in the environmental matrices. To prevent the spread of the panzootic disease, revised guidelines should be issued for the remediation of the virus. Recent viral remediation methods such as membrane bioreactors and advanced oxidation methods can be used. Therefore, the present review puts a light on the current knowledge on the occurrence of coronaviruses in wastewater, the possible sources, fate, and removal strategies.

Potential intestinal infection and faecal-oral transmission of human coronaviruses

Human coronaviruses (HCoVs) were first described in 1960s for patients experiencing common cold. Since then, increasing number of HCoVs have been discovered, including those causing severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and the circulating coronavirus disease 2019 (COVID‐19), which can cause fatal respiratory disease in humans on infection. HCoVs are believed to spread mainly through respiratory droplets and close contact. However, studies have shown that a large proportion of patients with HCoV infection develop gastrointestinal (GI) symptoms, and many patients with confirmed HCoV infection have shown detectable viral RNA in their faecal samples. Furthermore, multiple in vitro and in vivo animal studies have provided direct evidence of intestinal HCoV infection. These data highlight the nature of HCoV GI infection and its potential faecal‐oral transmission. Here, we summarise the current findings on GI manifestations of HCoVs. We also discuss how HCoV GI infection might occur and the current evidence to establish the occurrence of faecal‐oral transmission.

Proteomic landscape of SARS-CoV-2– and MERS-CoV–infected primary human renal epithelial cells

Translatome and proteome analyses of human proximal and distal tubular cells during coronavirus infection reveal distinctive host cell response patterns important for viral replication and renal pathology.

Acute kidney injury is associated with mortality in COVID-19 patients. However, host cell changes underlying infection of renal cells with SARS-CoV-2 remain unknown and prevent understanding of the molecular mechanisms that may contribute to renal pathology. Here, we carried out quantitative translatome and whole-cell proteomics analyses of primary renal proximal and distal tubular epithelial cells derived from human donors infected with SARS-CoV-2 or MERS-CoV to disseminate virus and cell type–specific changes over time. Our findings revealed shared pathways modified upon infection with both viruses, as well as SARS-CoV-2-specific host cell modulation driving key changes in innate immune activation and cellular protein quality control. Notably, MERS-CoV infection–induced specific changes in mitochondrial biology that were not observed in response to SARS-CoV-2 infection. Furthermore, we identified extensive modulation in pathways associated with kidney failure that changed in a virus- and cell type–specific manner. In summary, we provide an overview of the effects of SARS-CoV-2 or MERS-CoV infection on primary renal epithelial cells revealing key pathways that may be essential for viral replication.

Label-Free Detection of Human Coronaviruses in Infected Cells Using Enhanced Darkfield Hyperspectral Microscopy (EDHM)

Human coronaviruses (HCoV) are causative agents of mild to severe intestinal and respiratory infections in humans. In the last 15 years, we have witnessed the emergence of three zoonotic, highly pathogenic HCoVs. Thus, early and accurate detection of these viral pathogens is essential for preventing transmission and providing timely treatment and monitoring of drug resistance. Herein, we applied enhanced darkfield hyperspectral microscopy (EDHM), a novel non-invasive, label-free diagnostic tool, to rapidly and accurately identify two strains of HCoVs, i.e., OC43 and 229E. The EDHM technology allows collecting the optical image with spectral and spatial details in a single measurement without direct contact between the specimen and the sensor. Thus, it can directly map spectral signatures specific for a given viral strain in a complex biological milieu. Our study demonstrated distinct spectral patterns for HCoV-OC43 and HCoV-229E virions in the solution, serving as distinguishable parameters for their differentiation. Furthermore, spectral signatures obtained for both HCoV strains in the infected cells displayed a considerable peak wavelength shift compared to the uninfected cell, indicating that the EDHM is applicable to detect HCoV infection in mammalian cells.

One Health: EAACI Position Paper on coronaviruses at the human-animal interface, with a specific focus on comparative and zoonotic aspects of SARS-CoV-2

The latest outbreak of a coronavirus disease in 2019 (COVID‐19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), evolved into a worldwide pandemic with massive effects on health, quality of life, and economy. Given the short period of time since the outbreak, there are several knowledge gaps on the comparative and zoonotic aspects of this new virus. Within the One Health concept, the current EAACI position paper dwells into the current knowledge on SARS‐CoV‐2’s receptors, symptoms, transmission routes for human and animals living in close vicinity to each other, usefulness of animal models to study this disease and management options to avoid intra‐ and interspecies transmission. Similar pandemics might appear unexpectedly and more frequently in the near future due to climate change, consumption of exotic foods and drinks, globe‐trotter travel possibilities, the growing world population, the decreasing production space, declining room for wildlife and free‐ranging animals, and the changed lifestyle including living very close to animals. Therefore, both the society and the health authorities need to be aware and well prepared for similar future situations, and research needs to focus on prevention and fast development of treatment options (medications, vaccines).

Matrix metalloproteinases and tissue inhibitors of metalloproteinases in murine β-coronavirus-induced neuroinflammation

Mouse hepatitis virus (MHV; m-β-CoV) serves as a useful model for studying the cellular factors involved in neuroinflammation. To understand the role of matrix metalloproteinases (MMPs) in neuroinflammation, brain tissues from m-β-CoV-infected mice were harvested at different days post-infection (d.p.i) and investigated for Mmp expression by RT-qPCR. Mmp-2, -3, -8, -12 showed significant mRNA upregulation peaking with viral replication between 5 and 6 d.p.i. Elevated levels of MMP regulator TIMP-1 are suggestive of a TIMP-1 mediated host antiviral response. Biological network assessment suggested a direct involvement of MMP-3, -8, -14 in facilitating peripheral leukocyte infiltrations. Flow cytometry confirmed the increased presence of NK cells, CD4⁺ and CD8⁺ T cells, neutrophils, and MHCII expressing cells in the m-β-CoV infected mice brain. Our study revealed that m-β-CoV upregulated Park7, RelA, Nrf2, and Hmox1 transcripts involved in ROS production and antioxidant pathways, describing the possible nexus between oxidative pathways, MMPs, and TIMP in m-β-CoV-induced neuroinflammation.

MERS-CoV Confirmation among 6,873 suspected persons and relevant Epidemiologic and Clinical Features, Saudi Arabia - 2014 to 2019

BACKGROUND

Of the three lethal coronaviruses, in addition to the ongoing pandemic-causing SARS-CoV 2, Middle East Respiratory Syndrome Coronavirus (MERS-CoV) remains in circulation. Information on MERS-CoV has relied on small sample of patients. We updated the epidemiology, laboratory and clinical characteristics, and survival patterns of MERS-CoV retrospectively with the largest sample of followed patients.

METHODS

We conducted a retrospective review of line-listed records of non-random, continuously admitted patients who were suspected (6,873) or confirmed with MERS-CoV (501) admitted to one of the four MERS-CoV referral hospitals in Saudi Arabia, 2014-2019.

FINDINGS

Of the 6,873 MERS-CoV suspected persons, the majority were male (56%) and Saudi nationals (83%) and 95% had no known history that increased their risk of exposure to MERS-CoV patients or vectors (95%). More confirmed cases reported history that increased their risk of MERS-CoV infection (41%). Among the suspected, MERS-CoV confirmation (7.4% overall) was independently associated with being male, known transmission link to MERS-CoV patients or vectors, fever, symptoms for 7 days, admission through intensive care unit, and diabetes. Among persons with confirmed MERS-CoV, single symptoms were reported by 20%, 3-symptom combinations (fever, cough and dyspnea) reported by 21% and 2-symptom combinations (fever, cough) reported by 16%. Of the two-thirds (62%) of MERS-CoV confirmed patients who presented with co-morbidity, 32% had 2-"comorbidities (diabetes, hypertension). More than half of the MERS-CoV patents showed abnormal chest X-ray, elevated aspartate aminotransferase, and creatinine kinase. About a quarter of MERS-CoV patients had positive cultures on blood, urine, or respiratory secretions. During an average hospital stay of 18 days (range 11 to 30), 64% developed complications involving liver, lungs, or kidneys. Ventilation requirement (29% of MERS-CoV cases) was independently associated with abnormal chest X-ray, viremia (Ct value <30), elevated creatinine, and prothrombin time. Death (21% overall) was independently associated with older age, dyspnea and abnormal chest X-ray on admission, and low hemoglobulin levels.

INTERPRETATIONS

With two-thirds of the symptomatic persons developing multiorgan complications MERS-CoV remains the coronavirus with the highest severity (29%) and case fatality rate (21%) among the three lethal coronaviruses. Metabolic abnormalities appear to be an independent risk factor for sustained MERS-CoV transmission. The poorly understood transmission dynamics and non-specific clinical and laboratory features call for high index of suspicion among respiratory disease experts to help early detection of outbreaks. We reiterate the need for case control studies on transmission.

FUNDING

No special funding to declare.

Stem cell-based and mesenchymal stem cell derivatives for coronavirus treatment

Coronavirus disease 2019 (COVID-19) as one of the types of pneumonia was first reported in Wuhan, China in December 2019. COVID-19 is considered the third most common coronavirus among individuals after acute respiratory syndrome (SARS-CoV) and the Middle East respiratory syndrome (MERS-CoV) in the 20th century. Many studies have shown that cell therapy and regenerative medicine approaches have an impressive effect on different dangerous diseases in a way that using a cell-based experiment could be effective for improving humans with severe acute respiratory infections caused by the 2019 novel coronavirus. Accordingly, due to the stunning effects of mesenchymal stem cells (MSCs) and derivatives on the treatment of various diseases, this review focuses on the auxiliary role of MSCs and their derivatives in reducing the inflammatory processes of acute respiratory infections resulted from the 2019 novel coronavirus. The reported MSCs treatment outcomes are significant because these cells prevent the immune system from overactivating and improve, endogenous repair by improving the lung microenvironment after the SARS-CoV-2 infection. The MSCs can be an effective, autologous, and safe treatment, and therefore, share the results. To date, the results of several studies have shown that MSCs and their derivatives can inhibit inflammation. Exosomes act as intercellular communication devices between cells for the transfer of active molecules. In this review, recent MSCs and their derivatives-based clinical trials for the cure of COVID-19 are introduced.

Detection of three pandemic causing coronaviruses from non-respiratory samples: systematic review and meta-analysis

SARS-CoV-2 has posed an unprecedented challenge to the world. Pandemics have been caused previously by viruses of this family like Middle East Respiratory Corona Virus (MERS CoV), Severe Acute Respiratory Syndrome Corona Virus (SARS CoV). Although these viruses are primarily respiratory viruses, but they have been isolated from non-respiratory samples as well. Presently, the detection rate of SARS-CoV-2 RNA from different clinical specimens using Real Time Reverse Transcriptase Polymerized Chain Reaction (qRT-PCR) after onset of symptoms is not yet well established. Therefore, the aim of this systematic review was to establish the profile of detecting SARS-CoV-2, MERS CoV, SARS CoV from different types of clinical specimens other than the respiratory using a standard diagnostic test (qRT-PCR). A total of 3429 non-respiratory specimens were recorded: SARS CoV (total sample-802), MERS CoV (total sample-155), SARS CoV-2 (total sample-2347). Out of all the samples studied high positive rate was seen for saliva with 96.7% (14/14; 95% CI 87.6-100.0%) for SARS CoV and 57.5% (58/250; 95% CI - 1.2 to 116.2%) for SARS CoV-2, while low detection rate in urine samples for SARS CoV-2 with 2.2% (8/318; 95% CI 0.6-3.7%) and 9.6% (12/61; 95% CI - 0.9 to 20.1%) for SARS CoV but there was relatively higher positivity in urine samples for MERS CoV with detection rate of 32.4% (2/38; 95% CI - 37.3 to 102.1%). In Stool sample positivity was 54.9% (396/779; 95% CI 41.0-68.8%), 45.2% (180/430; 95% CI 28.1-62.3%) and 34.7% (4/38; 95% CI - 29.5 to 98.9%) for SARS CoV-2, MERS CoV, and SARS CoV, respectively. In blood sample the positivity was 33.3% (7/21; 95% CI 13.2-53.5%), 23.7% (42/277; 95% CI 10.5-36.9%) and 2.5% (2/81; 95% CI 0.00-5.8%) for MERS CoV, SARS CoV-2 and SARS CoV respectively. SARS-CoV-2 along with previous two pandemic causing viruses from this family, were highly detected stool and saliva. A low positive rate was recorded in blood samples. Viruses were also detected in fluids along with unusual samples like semen and vaginal secretions thus highlighting unique pathogenic potential of SARS-CoV-2.

Pathological diagnosis of Coronavirus-related nephropathy: insight from postmortem studies

A novel coronavirus pneumonia first occurred in Wuhan, China in early December 2019; the causative agent was identified and named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the World Health Organization (WHO), and the resulting disease termed coronavirus disease 2019 (COVID-19), according to the WHO coronavirus disease situation reports. This condition has spread rapidly all over the world and caused more than 125 million cases globally, with more than 2 million related deaths. Two previous outbreaks due to zoonotic coronaviruses have occurred in the last 20 years, namely the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), causing high morbidity and mortality in human populations upon crossing the species barriers. SARS-CoV-2, SARS-CoV, and MERS-CoV show several similarities in pathogenicity and clinical presentations, the latter ranging from asymptomatic infection to severe acute respiratory distress syndrome (ARDS) and multiorgan impairment. Acute kidney injury (AKI) has been commonly reported in patients with CoV infections; therefore, pathological analysis of renal parenchyma in these patients has been carried out in order to improve knowledge about underlying mechanisms. Viral infection has been demonstrated in the renal tubular epithelial cells by electron microscopy (EM), immunohistochemistry (IHC), and in situ hybridization (ISH), although with conflicting results. Light microscopy (LM) changes have been described in the renal parenchyma primarily in the form of acute renal tubular damage, possibly due to direct viral cytopathic effect and immune-mediated mechanisms such as cytokine storm syndrome. In this review, we describe and discuss the spectrum of histological, ultrastructural, and molecular findings in SARS-CoV, MERS-CoV, and SARS-CoV-2-related renal pathology obtained from postmortem studies, as well as intrinsic limitations and pitfalls of current diagnostic techniques.

Complement Anaphylatoxins and Inflammatory Cytokines as Prognostic Markers for COVID-19 Severity and In-Hospital Mortality

COVID-19 severity due to innate immunity dysregulation accounts for prolonged hospitalization, critical complications, and mortality. Severe SARS-CoV-2 infections involve the complement pathway activation for cytokine storm development. Nevertheless, the role of complement in COVID-19 immunopathology, complement-modulating treatment strategies against COVID-19, and the complement and SARS-CoV-2 interaction with clinical disease outcomes remain elusive. This study investigated the potential changes in complement signaling, and the associated inflammatory mediators, in mild-to-critical COVID-19 patients and their clinical outcomes. A total of 53 patients infected with SARS-CoV-2 were enrolled in the study (26 critical and 27 mild cases), and additional 18 healthy control patients were also included. Complement proteins and inflammatory cytokines and chemokines were measured in the sera of patients with COVID-19 as well as healthy controls by specific enzyme-linked immunosorbent assay. C3a, C5a, and factor P (properdin), as well as interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, and IgM antibody levels, were higher in critical COVID-19 patients compared to mild COVID-19 patients. Additionally, compared to the mild COVID-19 patients, factor I and C4-BP levels were significantly decreased in the critical COVID-19 patients. Meanwhile, RANTES levels were significantly higher in the mild patients compared to critical patients. Furthermore, the critical COVID-19 intra-group analysis showed significantly higher C5a, C3a, and factor P levels in the critical COVID-19 non-survival group than in the survival group. Additionally, IL-1β, IL-6, and IL-8 were significantly upregulated in the critical COVID-19 non-survival group compared to the survival group. Finally, C5a, C3a, factor P, and serum IL-1β, IL-6, and IL-8 levels positively correlated with critical COVID-19 in-hospital deaths. These findings highlight the potential prognostic utility of the complement system for predicting COVID-19 severity and mortality while suggesting that complement anaphylatoxins and inflammatory cytokines are potential treatment targets against COVID-19.

A critical review on SARS-CoV-2 infectivity in water and wastewater. What do we know?

The COVID-19 outbreak circulating the world is far from being controlled, and possible contamination routes are still being studied. There are no confirmed cases yet, but little is known about the infection possibility via contact with sewage or contaminated water as well as with aerosols generated during the pumping and treatment of these aqueous matrices. Therefore, this article presents a literature review on the detection of SARS-CoV-2 in human excreta and its pathways through the sewer system and wastewater treatment plants until it reaches the water bodies, highlighting their occurrence and infectivity in sewage and natural water. Research lines are still indicated, which we believe are important for improving the detection, quantification, and mainly the infectivity analyzes of SARS-CoV-2 and other enveloped viruses in sewage and natural water. In fact, up till now, no case of transmission via contact with sewage or contaminated water has been reported and the few studies conducted with these aqueous matrices have not detected infectious viruses. On the other hand, studies are showing that SARS-CoV-2 can remain viable, i.e., infectious, for up to 4.3 and 6 days in sewage and water, respectively, and that other species of coronavirus may remain viable in these aqueous matrices for more than one year, depending on the sample conditions. These are strong pieces of evidence that the contamination mediated by contact with sewage or contaminated water cannot be ruled out, even because other more resistant and infectious mutations of SARS-CoV-2 may appear.

SARS-CoV-2: sewage surveillance as an early warning system and challenges in developing countries

Transmission of novel coronavirus (SARS-CoV-2) in humans happens either through airway exposure to respiratory droplets from an infected patient or by touching the virus contaminated surface or objects (fomites). Presence of SARS-CoV-2 in human feces and its passage to sewage system is an emerging concern for public health. Pieces of evidence of the occurrence of viral RNA in feces and municipal wastewater (sewage) systems have not only warned reinforcing the treatment facilities but also suggest that these systems can be monitored to get epidemiological data for checking trend of COVID-19 infection in the community. This review summarizes the occurrence and persistence of novel coronavirus in sewage with an emphasis on the possible water environment contamination. Monitoring of novel coronavirus (SARS-CoV-2) via sewage-based epidemiology could deliver promising information regarding rate of infection providing a valid and complementary tool for tracking and diagnosing COVID-19 across communities. Tracking the sewage systems could act as an early warning tool for alerting the public health authorities for necessary actions. Given the impracticality of testing every citizen with limited diagnostic resources, it is imperative that sewage-based epidemiology can be tested as an early warning system. The need for the development of robust sampling strategies and subsequent detection methodologies and challenges for developing countries are also discussed.

Role of Inflammatory Cytokines in COVID-19 Patients: A Review on Molecular Mechanisms, Immune Functions, Immunopathology and Immunomodulatory Drugs to Counter Cytokine Storm

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a severe pandemic of the current century. The vicious tentacles of the disease have been disseminated worldwide with unknown complications and repercussions. Advanced COVID-19 syndrome is characterized by the uncontrolled and elevated release of pro-inflammatory cytokines and suppressed immunity, leading to the cytokine storm. The uncontrolled and dysregulated secretion of inflammatory and pro-inflammatory cytokines is positively associated with the severity of the viral infection and mortality rate. The secretion of various pro-inflammatory cytokines such as TNF-α, IL-1, and IL-6 leads to a hyperinflammatory response by recruiting macrophages, T and B cells in the lung alveolar cells. Moreover, it has been hypothesized that immune cells such as macrophages recruit inflammatory monocytes in the alveolar cells and allow the production of large amounts of cytokines in the alveoli, leading to a hyperinflammatory response in severely ill patients with COVID-19. This cascade of events may lead to multiple organ failure, acute respiratory distress, or pneumonia. Although the disease has a higher survival rate than other chronic diseases, the incidence of complications in the geriatric population are considerably high, with more systemic complications. This review sheds light on the pivotal roles played by various inflammatory markers in COVID-19-related complications. Different molecular pathways, such as the activation of JAK and JAK/STAT signaling are crucial in the progression of cytokine storm; hence, various mechanisms, immunological pathways, and functions of cytokines and other inflammatory markers have been discussed. A thorough understanding of cytokines' molecular pathways and their activation procedures will add more insight into understanding immunopathology and designing appropriate drugs, therapies, and control measures to counter COVID-19. Recently, anti-inflammatory drugs and several antiviral drugs have been reported as effective therapeutic drug candidates to control hypercytokinemia or cytokine storm. Hence, the present review also discussed prospective anti-inflammatory and relevant immunomodulatory drugs currently in various trial phases and their possible implications.

COVID-19 transmission, vulnerability, persistence and nanotherapy: a review

End 2019, the zoonotic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), named COVID-19 for coronavirus disease 2019, is the third adaptation of a contagious virus following the severe acute respiratory syndrome coronavirus in 2002, SARS-CoV, and the Middle East respiratory syndrome virus in 2012, MERS-CoV. COVID-19 is highly infectious and virulent compared to previous outbreaks. We review sources, contagious routes, preventive measures, pandemic, outbreak, epidemiology of SARS-CoV, MERS-CoV and SARS-CoV-2 from 2002 to 2020 using a Medline search. We discuss the chronology of the three coronaviruses, the vulnerability of healthcare workers, coronaviruses on surface and in wastewater, diagnostics and cures, and measures to prevent spreading.

Imaging features of COVID-19: What we can learn from SARS and MERS (Review)

Coronavirus disease 2019 (COVID-19) is a highly infectious type of pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that has rapidly become a global pandemic. COVID-19, SARS and Middle East respiratory syndrome (MERS) are all caused by members of the Coronaviridae family. As expected, emerging genetic and clinical evidence from patients with COVID-19 has indicated that the pathway of infection is similar to that of SARS and MERS. Additionally, much like SARS and MERS, chest imaging serves an important role in the diagnosis, management and follow-up of patients with COVID-19. Although these related viruses present a similar pneumonic pathogenesis, the imaging results have distinguishable features. The current review evaluated the imaging results of patients with SARS and MERS and explored the potential similarities and differences among patients with COVID-19, SARS and MERS at early, progressive, severe and recovery stages, with the aim of improving our understanding of SARS-CoV-2 infections by comparing the features of COVID-19 images with those of SARS and MERS. The current review assessed whether imaging results had implications for the administration of corticosteroids as treatment for COVID-19. Whether corticosteroids can inhibit inflammatory cytokine storms and reduce the mortality of patients with viral pneumonia remains controversial. However, his review may help radiologists and clinicians to identify viral pneumonia and guide appropriate COVID-19 treatment.

Successful recovery of a patient with multiple myeloma from severe coronavirus disease 2019 (COVID-19) pneumonia during the first chemotherapy cycle: A case report

A continuing outbreak of pneumonia associated with the 2019 novel coronavirus (2019-nCoV) was initially described in Wuhan, China in December 2019. Weak and elderly individuals, and those with chronic diseases such as hematological malignancies are prone to develop severe pneumonia. The humoral immunity of patients with multiple myeloma is prevalently low, and their inferior immunity further deteriorates during chemotherapy. For patients with onco-hematological malignancies infected with 2019-nCoV during the first chemotherapy cycle, the clinical treatment experience is lacking. The present study is a report of a 61-year-old patient newly diagnosed with multiple myeloma in the key 2019-nCoV outbreak area, who suffered severe 2019-nCoV pneumonia during the first chemotherapy cycle. The present case report demonstrated that a rapidly progressive and severe form of pneumonia was a specific clinical feature of COVID-19, especially in immunocompromised patients with cancer. The treatment strategy combining timely suspending chemotherapy, early intervention using intravenous immunoglobulin, interferon α inhalation and oral antiviral drugs was effective. Therefore, in the pandemic environment, it is strongly recommend that the risk of 2019-nCoV infection is assessed prior to chemotherapy.

Outcome of Middle East Respiratory Syndrome (MERS) in hematology and oncology patients: A case series in Saudi Arabia

BACKGROUND

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is associated with a high fatality rate (34%), which is higher in the presence of co-morbidities. The aim of the current study was to assess the clinical course and the outcome in hematological or oncological malignancy cases, diagnosed with MERS-CoV.

METHODS

This is a case series of hematological /oncological cases, diagnosed with MERS-CoV, in a tertiary care setting in 2015. The cases were identified based on the World Health Organization (WHO) MERS-CoV case definition. The demographic, clinical, and outcome data were retrieved from the patients' medical charts and electronic health records.

RESULTS

In total, nine hematological or oncological cases were identified, diagnosed with MERS-CoV. The baseline malignant condition was hematological malignancy in seven patients, as well as colon cancer and osteosarcoma in one patient each. Six (67%) patients were male. The median age was 65 years (range 16-80 years). Co-morbidities included chronic kidney disease (n = 3.33%), diabetes mellitus (n = 3.33%), and hypertension (n = 2.22%). The presenting symptoms were shortness of breath (n = 6.66%), fever (n = 5.55%), cough (n = 2.22%), and diarrhea (n = 2.22%). Chest x-rays indicated bilateral infiltrates in 6 patients (66%). The PCR (polymerase chain reaction) test was repeated in six patients to confirm the diagnosis. The mortality rate was 100%, and the median time to death was 26 days (range 15-77 days).

CONCLUSION

MERS-CoV infection in this small cohort of hematology or oncology patients has a 100% mortality rate, regardless of the status of the underlying disease. The confirmation of the diagnosis may require repeated testing. Additional studies are required to verify the findings and to elucidate the disease pathogenesis in cancer patients.

Application of Nanotechnology in the COVID-19 Pandemic

COVID-19, caused by SARS-CoV-2 infection, has been prevalent worldwide for almost a year. In early 2000, there was an outbreak of SARS-CoV, and in early 2010, a similar dissemination of infection by MERS-CoV occurred. However, no clear explanation for the spread of SARS-CoV-2 and a massive increase in the number of infections has yet been proposed. The best solution to overcome this pandemic is the development of suitable and effective vaccines and therapeutics. Fortunately, for SARS-CoV-2, the genome sequence and protein structure have been published in a short period, making research and development for prevention and treatment relatively easy. In addition, intranasal drug delivery has proven to be an effective method of administration for treating viral lung diseases. In recent years, nanotechnology-based drug delivery systems have been applied to intranasal drug delivery to overcome various limitations that occur during mucosal administration, and advances have been made to the stage where effective drug delivery is possible. This review describes the accumulated knowledge of the previous SARS-CoV and MERS-CoV infections and aims to help understand the newly emerged SARS-CoV-2 infection. Furthermore, it elucidates the achievements in developing COVID-19 vaccines and therapeutics to date through existing approaches. Finally, the applicable nanotechnology approach is described in detail, and vaccines and therapeutic drugs developed based on nanomedicine, which are currently undergoing clinical trials, have presented the potential to become innovative alternatives for overcoming COVID-19.

Nucleocapsid and Spike Proteins of the Coronavirus SARS-CoV-2 Induce IL6 in Monocytes and Macrophages-Potential Implications for Cytokine Storm Syndrome

The pandemic of the new coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) has led to the deaths of more than 1.5 million people worldwide. SARS-CoV-2 causes COVID-19, which exhibits wide variation in the course of disease in different people, ranging from asymptomatic and mild courses to very severe courses that can result in respiratory failure and death. Despite the rapid progression of knowledge, we still do not know how individual cells of the immune system interact with the virus or its components, or how immune homeostasis becomes disrupted, leading to the rapid deterioration of a patient's condition. In the present work, we show that SARS-CoV-2 proteins induce the expression and secretion of IL-6 by human monocytes and macrophages, the first line cells of antiviral immune responses. IL-6 may play a negative role in the course of COVID-19 by inhibiting Th1-dependent immunity and stimulating Th17 lymphocytes, thus leading to an increased probability of a cytokine storm.

The Cytokine Profiles and Immune Response Are Increased in COVID-19 Patients with Type 2 Diabetes Mellitus

The induction of inflammation and cytokine storm was proposed to play a critical role in COVID-19. This study is aimed at investigating the relationship between glucose metabolism and the inflammatory state of inpatients with COVID-19. 71 inpatients with COVID-19 were classified into nondiabetes mellitus (NDM) group, impaired fasting glucose (IFG) group, and diabetes mellitus (DM) group. The average hospitalization days were significantly shorter in DM patients when compared with patients in the IFG group and NDM group. CD4+ T cell percentage was higher while CD8+ T cells percentage was lower in the DM group than those in the NDM group. The serum levels of IL-6, IL-2, IL-10, and INF-γ in the DM group were upregulated when compared with those in the NDM group. The serum levels of TNF-α, IL-4, IL-2, IL-10, and INF-γ were significantly higher in the DM group than those in the IFG group. A significant difference was observed in CD4+ T cell, CD4+/CD8+ ratio percentage, IL-6, and IL-10 between the NDM group and DM group with adjusted BMI. In conclusion, COVID-19 patients with elevated glucose levels have promoted cytokine profiles and immune response.

Acute Kidney Injury and Covid-19: A Scoping Review and Meta-Analysis

Acute kidney injury (AKI) is a fatal complication of the new severe acute respiratory syndrome coronavirus (SARS-CoV-2) which causes COVID-19 disease. Here, we performed a scoping review and meta-analysis including clinical studies on patients with SARS-CoV-2 infection with data on AKI assessment and characteristics, and the overall prevalence of AKI was estimated using a random-effects model. We identified 21 articles which passed the search criteria. All were quantitative observational studies which used a cross-sectional, retrospective, case report, or cohort methodology. This showed that aging, diabetes, cardiovascular disease, previous chronic disease, and other comorbidities were risk factors of AKI. Although the prevalence of proteinuria, hematuria, and increased serum creatinine was reported for up to 60% of the patients with COVID-19, the overall prevalence of AKI was estimated to be 8%. We conclude that although approximately two-thirds of patients with COVID-19 had symptoms of kidney damage, most of these did not meet the diagnostic criteria for AKI. Further studies should be performed to validate biomarkers for improved AKI diagnosis in COVID-19 patients and new treatment options are required to reduce the rate of mortality.

Temporal evolution, most influential studies and sleeping beauties of the coronavirus literature

Following the outbreak of SARS-CoV-2 disease, within less than 8 months, the 50 years-old scholarly literature of coronaviruses grew to nearly three times larger than its size prior to 2020. Here, temporal evolution of the coronavirus literature over the last 30 years (N = 43,769) is analysed along with its subdomain of SARS-CoV-2 articles (N = 27,460) and the subdomain of reviews and meta-analytic studies (N = 1027). The analyses are conducted through the lenses of co-citation and bibliographic coupling of documents. (1) Of the N = 1204 review and meta-analytical articles of the coronavirus literature, nearly 88% have been published and indexed during the first 8 months of 2020, marking an unprecedented attention to reviews and meta-analyses in this domain, prompted by the SARS-CoV-2 pandemic. (2) The subset of 2020 SARS-CoV-2 articles is bibliographically distant from the rest of this literature published prior to 2020. Individual articles of the SARS-CoV-2 segment with a bridging role between the two bodies of articles (i.e., before and after 2020) are identifiable. (3) Furthermore, the degree of bibliographic coupling within the 2020 SARS-CoV-2 cluster is much poorer compared to the cluster of articles published prior to 2020. This could, in part, be explained by the higher diversity of topics that are studied in relation to SARS-CoV-2 compared to the literature of coronaviruses published prior to the SARS-CoV-2 disease. (4) The analyses on the subset of SARS-CoV-2 literature identified studies published prior to 2020 that have now proven highly instrumental in the development of various clusters of publications linked to SARS-CoV-2. In particular, the so-called "sleeping beauties" of the coronavirus literature with an awakening in 2020 were identified, i.e., previously published studies of this literature that had remained relatively unnoticed for several years but gained sudden traction in 2020 in the wake of the SARS-CoV-2 outbreak. This work documents the historical development of the literature on coronaviruses as an event-driven literature and as a domain that exhibited, arguably, the most exceptional case of publication burst in the history of science. It also demonstrates how scholarly efforts undertaken during peace time or prior to a disease outbreak could suddenly play a critical role in prevention and mitigation of health disasters caused by new diseases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11192-021-04036-4.

Review of analytical performance of COVID-19 detection methods

In the recent SARS-CoV-2 pandemic, public health experts have emphasized testing, tracking infected people, and tracing their contacts as an effective strategy to reduce the spread of the virus. Several diagnostic methods are reported for detecting the coronavirus in clinical, research, and public health laboratories. Some tests detect the infection directly by detecting the viral RNA and other tests detect the infection indirectly by detecting the host antibodies. A diagnostic test during the pandemic should help make an appropriate clinical decision in a short period of time. Recently reported diagnostic methods for SARS-CoV-2 have varying throughput, batching capacity, requirement of infrastructure setting, analytical performance, and turnaround times ranging from a few minutes to several hours. These factors should be considered while selecting a reliable and rapid diagnostic method to help make an appropriate decision and prompt public health interventions. This paper reviews recent SARS-CoV-2 diagnostic methods published in journals and reports released by regulatory agencies. We compared the analytical efficiency including limit of detection, sensitivity, specificity, and throughput. In addition, we also looked into ease of use, affordability, and availability of accessories. Finally, we discuss the limitations of the methods and provide our perspectives on priorities for future test development.

Shedding of SARS-CoV-2 in feces and urine and its potential role in person-to-person transmission and the environment-based spread of COVID-19

The recent detection of SARS-CoV-2 RNA in feces has led to speculation that it can be transmitted via the fecal-oral/ocular route. This review aims to critically evaluate the incidence of gastrointestinal (GI) symptoms, the quantity and infectivity of SARS-CoV-2 in feces and urine, and whether these pose an infection risk in sanitary settings, sewage networks, wastewater treatment plants, and the wider environment (e.g. rivers, lakes and marine waters). A review of 48 independent studies revealed that severe GI dysfunction is only evident in a small number of COVID-19 cases, with 11 ± 2% exhibiting diarrhea and 12 ± 3% exhibiting vomiting and nausea. In addition to these cases, SARS-CoV-2 RNA can be detected in feces from some asymptomatic, mildly- and pre-symptomatic individuals. Fecal shedding of the virus peaks in the symptomatic period and can persist for several weeks, but with declining abundances in the post-symptomatic phase. SARS-CoV-2 RNA is occasionally detected in urine, but reports in fecal samples are more frequent. The abundance of the virus genetic material in both urine (ca. 102-105 gc/ml) and feces (ca. 102-107 gc/ml) is much lower than in nasopharyngeal fluids (ca. 105-1011 gc/ml). There is strong evidence of multiplication of SARS-CoV-2 in the gut and infectious virus has occasionally been recovered from both urine and stool samples. The level and infectious capability of SARS-CoV-2 in vomit remain unknown. In comparison to enteric viruses transmitted via the fecal-oral route (e.g. norovirus, adenovirus), the likelihood of SARS-CoV-2 being transmitted via feces or urine appears much lower due to the lower relative amounts of virus present in feces/urine. The biggest risk of transmission will occur in clinical and care home settings where secondary handling of people and urine/fecal matter occurs. In addition, while SARS-CoV-2 RNA genetic material can be detected by in wastewater, this signal is greatly reduced by conventional treatment. Our analysis also suggests the likelihood of infection due to contact with sewage-contaminated water (e.g. swimming, surfing, angling) or food (e.g. salads, shellfish) is extremely low or negligible based on very low predicted abundances and limited environmental survival of SARS-CoV-2. These conclusions are corroborated by the fact that tens of million cases of COVID-19 have occurred globally, but exposure to feces or wastewater has never been implicated as a transmission vector.

Shedding of SARS-CoV-2 in feces and urine and its potential role in person-to-person transmission and the environment-based spread of COVID-19

The recent detection of SARS-CoV-2 RNA in feces has led to speculation that it can be transmitted via the fecal-oral/ocular route. This review aims to critically evaluate the incidence of gastrointestinal (GI) symptoms, the quantity and infectivity of SARS-CoV-2 in feces and urine, and whether these pose an infection risk in sanitary settings, sewage networks, wastewater treatment plants, and the wider environment (e.g. rivers, lakes and marine waters). A review of 48 independent studies revealed that severe GI dysfunction is only evident in a small number of COVID-19 cases, with 11 ± 2% exhibiting diarrhea and 12 ± 3% exhibiting vomiting and nausea. In addition to these cases, SARS-CoV-2 RNA can be detected in feces from some asymptomatic, mildly- and pre-symptomatic individuals. Fecal shedding of the virus peaks in the symptomatic period and can persist for several weeks, but with declining abundances in the post-symptomatic phase. SARS-CoV-2 RNA is occasionally detected in urine, but reports in fecal samples are more frequent. The abundance of the virus genetic material in both urine (ca. 10²-10⁵ gc/ml) and feces (ca. 10²-10⁷ gc/ml) is much lower than in nasopharyngeal fluids (ca. 10⁵-10¹¹ gc/ml). There is strong evidence of multiplication of SARS-CoV-2 in the gut and infectious virus has occasionally been recovered from both urine and stool samples. The level and infectious capability of SARS-CoV-2 in vomit remain unknown. In comparison to enteric viruses transmitted via the fecal-oral route (e.g. norovirus, adenovirus), the likelihood of SARS-CoV-2 being transmitted via feces or urine appears much lower due to the lower relative amounts of virus present in feces/urine. The biggest risk of transmission will occur in clinical and care home settings where secondary handling of people and urine/fecal matter occurs. In addition, while SARS-CoV-2 RNA genetic material can be detected by in wastewater, this signal is greatly reduced by conventional treatment. Our analysis also suggests the likelihood of infection due to contact with sewage-contaminated water (e.g. swimming, surfing, angling) or food (e.g. salads, shellfish) is extremely low or negligible based on very low predicted abundances and limited environmental survival of SARS-CoV-2. These conclusions are corroborated by the fact that tens of million cases of COVID-19 have occurred globally, but exposure to feces or wastewater has never been implicated as a transmission vector.

Shedding of SARS-CoV-2 in feces and urine and its potential role in person-to-person transmission and the environment-based spread of COVID-19

The recent detection of SARS-CoV-2 RNA in feces has led to speculation that it can be transmitted via the fecal-oral/ocular route. This review aims to critically evaluate the incidence of gastrointestinal (GI) symptoms, the quantity and infectivity of SARS-CoV-2 in feces and urine, and whether these pose an infection risk in sanitary settings, sewage networks, wastewater treatment plants, and the wider environment (e.g. rivers, lakes and marine waters). A review of 48 independent studies revealed that severe GI dysfunction is only evident in a small number of COVID-19 cases, with 11 ± 2% exhibiting diarrhea and 12 ± 3% exhibiting vomiting and nausea. In addition to these cases, SARS-CoV-2 RNA can be detected in feces from some asymptomatic, mildly- and pre-symptomatic individuals. Fecal shedding of the virus peaks in the symptomatic period and can persist for several weeks, but with declining abundances in the post-symptomatic phase. SARS-CoV-2 RNA is occasionally detected in urine, but reports in fecal samples are more frequent. The abundance of the virus genetic material in both urine (ca. 10²-10⁵ gc/ml) and feces (ca. 10²-10⁷ gc/ml) is much lower than in nasopharyngeal fluids (ca. 10⁵-10¹¹ gc/ml). There is strong evidence of multiplication of SARS-CoV-2 in the gut and infectious virus has occasionally been recovered from both urine and stool samples. The level and infectious capability of SARS-CoV-2 in vomit remain unknown. In comparison to enteric viruses transmitted via the fecal-oral route (e.g. norovirus, adenovirus), the likelihood of SARS-CoV-2 being transmitted via feces or urine appears much lower due to the lower relative amounts of virus present in feces/urine. The biggest risk of transmission will occur in clinical and care home settings where secondary handling of people and urine/fecal matter occurs. In addition, while SARS-CoV-2 RNA genetic material can be detected by in wastewater, this signal is greatly reduced by conventional treatment. Our analysis also suggests the likelihood of infection due to contact with sewage-contaminated water (e.g. swimming, surfing, angling) or food (e.g. salads, shellfish) is extremely low or negligible based on very low predicted abundances and limited environmental survival of SARS-CoV-2. These conclusions are corroborated by the fact that tens of million cases of COVID-19 have occurred globally, but exposure to feces or wastewater has never been implicated as a transmission vector.

Clinical and Microbiological Features of Asymptomatic SARS-CoV-2 Infection and Mild COVID-19 in Seven Crewmembers of a Cruise Ship

Objective To describe the clinical features and clinical course of individuals diagnosed with asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or mild coronavirus disease (COVID)-19. Patients The study participants consisted of 7 crewmembers of the passenger cruise-liner, Diamond Princess, who were admitted to our hospital after becoming infected with SARS-CoV-2 aboard the ship. Methods The data on patient background and biochemical test results were obtained from the patients' medical records. All patients had a chest X-ray, and a throat swab and sputum samples were sent for culture on admission. Results The median age of the 7 patients, of whom 4 were male and 3 were female, was 39 years (range: 23-47 years). On admission, none of them had fever, but 4 (57%) had a cough. None of them showed any signs of organ damage on laboratory testing. Chest X-ray showed pneumonia in one individual, which resolved spontaneously, while the other 6 had normal chest X-ray findings. Culture of throat swabs and sputum samples revealed that 4 patients (57%) had bacterial upper respiratory infections (Haemophilus influenzae, Klebsiella pneumoniae, and Staphylococcus aureus). The period from a positive polymerase chain reaction (PCR) test to negative conversion ranged from 5 to 13 days, with a median of 8 days. Conclusion Healthy young adults without risk factors who acquire SARS-CoV-2 infection may have an asymptomatic infection or may experience mild COVID-19. In addition to obesity, an older age, underlying illness, and being overweight can lead to a risk of exacerbation; thus, hospital management for such individuals may be desirable. Culturing respiratory samples may be useful for diagnosing secondary bacterial pneumonia.

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.

Ticking bomb: Prolonged faecal shedding of novel coronavirus (2019-nCoV) and environmental implications

The current global coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a tremendous public health challenge globally. While the respiratory transmission of SARS-CoV-2 has been established, evolving reports on the impact of the gastrointestinal system and the prolonged faecal shedding of SARS-CoV-2 show the likelihood of faecally mediated transmission. The increasing evidential presence of SARS-CoV-2 in wastewater and faecal material poses a significant public health threat which may potentiate global vulnerability to high risk of human exposure through environmental drivers especially in less developed countries. While extensively exploring the likelihood of faecally mediated SARS-CoV-2 transmission, infection control and prevention measures aimed at mitigating this pandemic should holistically include environmental drivers.

SARS-CoV, MERS-CoV, and 2019-nCoV viruses: an overview of origin, evolution, and genetic variations

Coronaviruses are single stranded RNA viruses usually present in bats (reservoir hosts), and are generally lethal, highly transmissible, and pathogenic viruses causing sever morbidity and mortality rates in human. Several animals including civets, camels, etc. have been identified as intermediate hosts enabling effective recombination of these viruses to emerge as new virulent and pathogenic strains. Among the seven known human coronaviruses SARS-CoV, MERS-CoV, and SARS-CoV-2 (2019-nCoV) have evolved as severe pathogenic forms infecting the human respiratory tract. About 8096 cases and 774 deaths were reported worldwide with the SARS-CoV infection during year 2002; 2229 cases and 791 deaths were reported for the MERS-CoV that emerged during 2012. Recently ~ 33,849,737 cases and 1,012,742 deaths (data as on 30 Sep 2020) were reported from the recent evolver SARS-CoV-2 infection. Studies on epidemiology and pathogenicity have shown that the viral spread was potentially caused by the contact route especially through the droplets, aerosols, and contaminated fomites. Genomic studies have confirmed the role of the viral spike protein in virulence and pathogenicity. They target the respiratory tract of the human causing severe progressive pneumonia affecting other organs like central nervous system in case of SARS-CoV, severe renal failure in MERS-CoV, and multi-organ failure in SARS-CoV-2. Herein, with respect to current awareness and role of coronaviruses in global public health, we review the various factors involving the origin, evolution, and transmission including the genetic variations observed, epidemiology, and pathogenicity of the three potential coronaviruses variants SARS-CoV, MERS-CoV, and 2019-nCoV.

Systemic innate and adaptive immune responses to SARS-CoV-2 as it relates to other coronaviruses

The deadly pandemic caused by the novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) represents one of the greatest threats humanity has faced in the last century. Infection with this easily transmissible virus can run the gamut from asymptomatic to fatal, and the disease caused by SARS-CoV-2 has been termed Coronavirus Disease 2019 (COVID-19). What little research that has already been conducted implicates pathological responses by the immune system as the leading culprit responsible for much of the morbidity and mortality caused by COVID-19. In this review we will summarize what is currently known about the systemic immune response to SARS-CoV-2 and potential immunotherapeutic approaches.

Mathematical modeling of the spread of COVID-19 among different age groups in Morocco: Optimal control approach for intervention strategies

In this article, we study the transmission of COVID-19 in the human population, notably between potential people and infected people of all age groups. Our objective is to reduce the number of infected people, in addition to increasing the number of individuals who recovered from the virus and are protected. We propose a mathematical model with control strategies using two variables of controls that represent respectively, the treatment of patients infected with COVID-19 by subjecting them to quarantine within hospitals and special places and using masks to cover the sensitive body parts. Pontryagin's Maximum principle is used to characterize the optimal controls and the optimality system is solved by an iterative method. Finally, numerical simulations are presented with controls and without controls. Our results indicate that the implementation of the strategy that combines all the control variables adopted by the World Health Organization (WHO), produces excellent results similar to those achieved on the ground in Morocco.