Host-directed therapies for improving poor treatment outcomes associated with the middle east respiratory syndrome coronavirus infections

The role of extracellular histones in COVID-19

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had spread from China and, within 2 months, became a global pandemic. The infection from this disease can cause a diversity of symptoms ranging from asymptomatic to severe acute respiratory distress syndrome with an increased risk of vascular hyperpermeability, pulmonary inflammation, extensive lung damage, and thrombosis. One of the host defense systems against coronavirus disease 2019 (COVID-19) is the formation of neutrophil extracellular traps (NETs). Numerous studies on this disease have revealed the presence of elevated levels of NET components, such as cell-free DNA, extracellular histones, neutrophil elastase, and myeloperoxidase, in plasma, serum, and tracheal aspirates of severe COVID-19 patients. Extracellular histones, a major component of NETs, are clinically very relevant as they represent promising biomarkers and drug targets, given that several studies have identified histones as key mediators in the onset and progression of various diseases, including COVID-19. However, the role of extracellular histones in COVID-19 per se remains relatively underexplored. Histones are nuclear proteins that can be released into the extracellular space via apoptosis, necrosis, or NET formation and are then regarded as cytotoxic damage-associated molecular patterns that have the potential to damage tissues and impair organ function. This review will highlight the mechanisms of extracellular histone-mediated cytotoxicity and focus on the role that histones play in COVID-19. Thereby, this paper facilitates a bench-to-bedside view of extracellular histone-mediated cytotoxicity, its role in COVID-19, and histones as potential drug targets and biomarkers for future theranostics in the clinical treatment of COVID-19 patients.

Effectiveness and safety of available treatments for COVID-19 during pregnancy: a critical review

BACKGROUND

COVID-19 is a pandemic disease caused by the SARS-CoV-2 and it spread globally in the last few months. The complete lack of specific treatment forced clinicians to use old drugs, chosen for their efficacy against similar viruses or their in vitro activity. Trials on patients are ongoing but the majority of information comes from small case series and single center reports. We aimed to provide a literature review on the putative effectiveness and safety of available treatments for COVID-19 in pregnant women.

METHODS

We reviewed all the available literature concerning the drugs that have been used in the treatment of COVID-19 during pregnancy and whose safe assumption during pregnancy had been demonstrated by clinical studies (i.e. including studies on other infectious diseases). Drugs contra-indicated during pregnancy or with unknown adverse effects were not included in our review.

RESULTS AND CONCLUSIONS

Clinical trials are not often conducted among pregnant patients for safety reasons and this means that drugs that may be effective in general population cannot be used for pregnant women due to the lack of knowledge of side effects in this category of people .The choice to use a specific drug for COVID-19 in pregnancy should take into account benefits and possible adverse events in each single case. In the current situation of uncertainty and poor knowledge about the management of COVID-19 during pregnancy, this present overview may provide useful information for physicians with practical implications.

A review of COVID-19: Treatment strategies and CRISPR/Cas9 gene editing technology approaches to the coronavirus disease

The new coronavirus SARS-CoV-2 pandemic has put the world on lockdown for the first time in decades. This has wreaked havoc on the global economy, put additional burden on local and global public health resources, and, most importantly, jeopardised human health. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats, and the CRISPR associated (Cas) protein (CRISPR/Cas) was identified to have structures in E. coli. The most modern of these systems is CRISPR/Cas. Editing the genomes of plants and animals took several years and cost hundreds of thousands of dollars until the CRISPR approach was discovered in 2012. As a result, CRISPR/Cas has piqued the scientific community's attention, particularly for disease diagnosis and treatment, because it is faster, less expensive, and more precise than previous genome editing technologies. Data from gene mutations in specific patients gathered using CRISPR/Cas can aid in the identification of the best treatment strategy for each patient, as well as other research domains such as coronavirus replication in cell culture, such as SARS-CoV2. The implications of the most prevalent driver mutations, on the other hand, are often unknown, making treatment interpretation difficult. For detecting a wide range of target genes, the CRISPR/Cas categories provide highly sensitive and selective tools. Genome-wide association studies are a relatively new strategy to discovering genes involved in human disease when it comes to the next steps in genomic research. Furthermore, CRISPR/Cas provides a method for modifying non-coding portions of the genome, which will help advance whole genome libraries by speeding up the analysis of these poorly defined parts of the genome.

Going ballistic: Leishmania nuclear subversion of host cell plasticity

Intracellular parasites have evolved intricate strategies to subvert host cell functions for their own survival. These strategies are particularly damaging to the host if the infection involves immune cells, as illustrated by protozoan parasites of the genus Leishmania that thrive inside mononuclear phagocytic cells, causing devastating immunopathologies. While the impact of Leishmania infection on host cell phenotype and functions has been well documented, the regulatory mechanisms underlying host cell subversion were only recently investigated. Here we summarize the current knowledge on how Leishmania infection affects host nuclear activities and propose thought-provoking new concepts on the reciprocal relationship between epigenetic and transcriptional regulation in host cell phenotypic plasticity, its potential subversion by the intracellular parasite, and its relevance for host-directed therapy.

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.

Genetic Risk Factors for the Development of COVID-19 Coronavirus Infection

The COVID-19 coronavirus pandemic has spread to 215 countries around the world and caused tens of millions of infections and more than a million deaths worldwide. In the midst of COVID-19 infection, it is extremely important to identify new protein and gene targets that may be highly sensitive diagnostic and prognostic markers of the severity and outcome of the disease for combating this pandemic. Identification of individual genetic predisposition allows personalizing programs of medical rehabilitation and therapy. It has now been shown that the transmissibility and severity of COVID-19 infection can be affected by gene variants in both the human body (ACE2, HLA-B*4601, FcγRIIA, MBL, TMPRSS2, TNFA, IL6, blood group A antigen, etc.) and the virus itself (ORF8 in RNA polymerase, ORF6 in RNA primase, S, N, E proteins). The presence of mutations in the proteins of the virus can change the affinity and specificity for the binding of targeted drugs to them, being the molecular basis of individual differences in the response of the human body to antiviral drugs and/or vaccines. The review summarizes the data on the variants of the genomes of the coronavirus and humans associated with an individual predisposition to an increased or decreased risk of transmission, severity, and outcome of COVID-19 infection. Targeted drugs and vaccines being developed for the therapy of COVID-19 infection are briefly reviewed.

Shedding light on therapeutics in alopecia and their relevance to COVID-19

As of July 9, 2020, there were more than 12 million confirmed cases of coronavirus disease 2019 (COVID-19) across the globe, with more than 550,000 deaths. Many European countries, including Belgium, the United Kingdom, Italy, and Spain, have had the highest numbers of fatalities per capita. This indicates the potential for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus to overwhelm even the most advanced health care systems despite extreme societal interventions. Since its emergence, SARS-CoV-2 has disseminated across the globe, affecting the structure of global societies, infrastructure, and economies. Patients with alopecia are a diverse group who, for various indications, are prescribed a number of antimicrobials and antiandrogen treatments in addition to immunomodulatory therapies such as hydroxychloroquine, oral corticosteroids, and a range of broad immunosuppressants. These drugs are being scrutinized for their capacity to potentially affect SARS-CoV-2 outcomes. We examine these treatments and highlight the critical role that patient registries will play in generating real-world evidence to assess their impact on COVID-19 outcomes.

Potential of natural astaxanthin in alleviating the risk of cytokine storm in COVID-19

Host excessive inflammatory immune response to SARS-CoV-2 infection is thought to underpin the pathogenesis of COVID-19 associated severe pneumonitis and acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Once an immunological complication like cytokine storm occurs, anti-viral based monotherapy alone is not enough. Additional anti-inflammatory treatment is recommended. It must be noted that anti-inflammatory drugs such as JAK inhibitors, IL-6 inhibitors, TNF-α inhibitors, colchicine, etc., have been either suggested or are under trials for managing cytokine storm in COVID-19 infections. Natural astaxanthin (ASX) has a clinically proven safety profile and has antioxidant, anti-inflammatory, and immunomodulatory properties. There is evidence from preclinical studies that supports its preventive actions against ALI/ARDS. Moreover, ASX has a potent PPARs activity. Therefore, it is plausible to speculate that ASX could be considered as a potential adjunctive supplement. Here, we summarize the mounting evidence where ASX is shown to exert protective effect by regulating the expression of pro-inflammatory factors IL-1β, IL-6, IL-8 and TNF-α. We present reports where ASX is shown to prevent against oxidative damage and attenuate exacerbation of the inflammatory responses by regulating signaling pathways like NF-ĸB, NLRP3 and JAK/STAT. These evidences provide a rationale for considering natural astaxanthin as a therapeutic agent against inflammatory cytokine storm and associated risks in COVID-19 infection and this suggestion requires further validation with clinical studies.

Interleukin-6 in Covid-19: A systematic review and meta-analysis

Coronaviruses may activate dysregulated host immune responses. As exploratory studies have suggested that interleukin-6 (IL-6) levels are elevated in cases of complicated Covid-19, we undertook a systematic review and meta-analysis to assess the evidence in this field. We systematically searched MEDLINE and EMBASE for studies investigating the immunological response in Covid-19; additional grey literature searches were undertaken. Study selection and data abstraction was undertaken independently by two authors. Meta-analysis was undertaken using random effects models to compute ratios of means with 95% confidence intervals (95%CIs). Eight published studies and two preprints (n = 1798) were eligible for inclusion. Meta-analysis of mean IL-6 concentrations demonstrated 2.9-fold higher levels in patients with complicated Covid-19 compared with patients with noncomplicated disease (six studies; n = 1302; 95%CI, 1.17-7.19; I² = 100%). Consistent results were found in sensitivity analyses exclusively restricted to studies comparing patients requiring ICU admission vs no ICU admission (two studies; n = 540; ratio of means = 3.24; 95%CI, 2.54-4.14; P < .001; I² = 87%). Nine of ten studies were assessed to have at least moderate risk of bias. In patients with Covid-19, IL-6 levels are significantly elevated and associated with adverse clinical outcomes. Inhibition of IL-6 may be a novel target for therapeutics for the management of dysregulated host responses in patients with Covid-19 and high-quality studies of intervention in this field are urgently required.

Interleukin-6 in Covid-19: A systematic review and meta-analysis

Coronaviruses may activate dysregulated host immune responses. As exploratory studies have suggested that interleukin-6 (IL-6) levels are elevated in cases of complicated Covid-19, we undertook a systematic review and meta-analysis to assess the evidence in this field. We systematically searched MEDLINE and EMBASE for studies investigating the immunological response in Covid-19; additional grey literature searches were undertaken. Study selection and data abstraction was undertaken independently by two authors. Meta-analysis was undertaken using random effects models to compute ratios of means with 95% confidence intervals (95%CIs). Eight published studies and two preprints (n = 1798) were eligible for inclusion. Meta-analysis of mean IL-6 concentrations demonstrated 2.9-fold higher levels in patients with complicated Covid-19 compared with patients with noncomplicated disease (six studies; n = 1302; 95%CI, 1.17-7.19; I² = 100%). Consistent results were found in sensitivity analyses exclusively restricted to studies comparing patients requiring ICU admission vs no ICU admission (two studies; n = 540; ratio of means = 3.24; 95%CI, 2.54-4.14; P < .001; I² = 87%). Nine of ten studies were assessed to have at least moderate risk of bias. In patients with Covid-19, IL-6 levels are significantly elevated and associated with adverse clinical outcomes. Inhibition of IL-6 may be a novel target for therapeutics for the management of dysregulated host responses in patients with Covid-19 and high-quality studies of intervention in this field are urgently required.

The Current Recommended Drugs and Strategies for the Treatment of Coronavirus Disease (COVID-19)

BACKGROUND

The coronavirus 2019 (COVID-19) has been known as a pandemic disease by the World Health Organization (WHO) worldwide. The drugs currently used for treatment of COVID-19 are often selected and tested based on their effectiveness in other diseases such as influenza and AIDS and their major identified targets are viral protease, host cell produced protease, viral RNA polymerase, and the interaction site of viral protein with host cell receptors. Until now, there are no approved therapeutic drugs for definitive treatment of this dangerous disease.

METHODS

In this article, all of the documentary information, such as clinical trials, original research and reviews, government's database, and treatment guidelines, were reviewed critically and comprehensively. Moreover, it was attempted to present the most common and effective drugs and strategies, to suggest the possible treatment way of COVID19 by focusing on the body's defense mechanism against pathogens.

RESULTS

Antiviral drugs and immune-modulatory agents with the traditional medicines using the natural compound are usual accessible treatments. Accordingly, they have better beneficence due to the large existence studies, long time follow-ups, proximity to the natural system, and the normal physiological routine of the pathogen and host interactions. Besides, the serotonergic and dopaminergic pathways are considered as attractive targets to treat human immune, infectious, and cancerous diseases. Fluoxetine, as a host-targeted small molecule with immunomodulatory action, may be known as effective drug for treatment and prevention of COVID19 disease, in combination with antiviral drugs and natural compounds.

CONCLUSION

Co-administration of fluoxetine in the treatment of COVID19 could be considered due to the possibility of its interaction with ACE2 receptors, immune-modulatory function, and a proper immune response at the right time. Fluoxetine plays a beneficial role in reducing stress due to fear of infecting by COVID19 or worsening the disease and psychological support for the affected patients.

The use of mesenchymal stromal cells in the treatment of coronavirus disease 2019

More than seven months into the coronavirus disease -19 (COVID-19) pandemic, infection from the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to over 21.2 million cases and resulted in over 760,000 deaths worldwide so far. As a result, COVID-19 has changed all our lives as we battle to curtail the spread of the infection in the absence of specific therapies against coronaviruses and in anticipation of a proven safe and efficacious vaccine. Common with previous outbreaks of coronavirus infections, SARS and Middle East respiratory syndrome, COVID-19 can lead to acute respiratory distress syndrome (ARDS) that arises due to an imbalanced immune response. While several repurposed antiviral and host-response drugs are under examination as potential treatments, other novel therapeutics are also being explored to alleviate the effects on critically ill patients. The use of mesenchymal stromal cells (MSCs) for COVID-19 has become an attractive avenue down which almost 70 different clinical trial teams have ventured. Successfully trialled for the treatment of other conditions such as multiple sclerosis, osteoarthritis and graft versus host disease, MSCs possess both regenerative and immunomodulatory properties, the latter of which can be harnessed to reduce the severity and longevity of ARDS in patients under intensive care due to SARS-CoV-2 infection.

Clinical manifestations and maternal and perinatal outcomes with COVID-19

Coronavirus disease 2019 (COVID-19) is a novel type of highly contagious pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the COVID-19 outbreak unfolds, more and more pregnant women are infected with SARS-CoV-2, concerns have been raised about its clinical manifestations in pregnancy and the potential risk of vertical transmission from mother to fetus in pregnant women. Hence, in this review, we summarize the latest research progress related to COVID-19 epidemiology and the reported data of pregnant women with COVID-19 and discuss the clinical manifestations, treatments, maternal and perinatal outcomes, and intrauterine vertical transmission potential of such virus. Reported data suggest that symptoms in pregnant women are similar to those in other populations and that there is no evidence of vertical transmission from mother to child. In the meantime, considering the good prognosis of most of the infected mothers and infants and absence of serious obstetric complications in pregnant women with COVID-19, it is not recommended to give birth as soon as possible, and it is necessary to extend the gestational period reasonably.

Potential drugs for the treatment of the novel coronavirus pneumonia (COVID-19) in China

The fight against the novel coronavirus pneumonia (namely COVID-19) that seriously harms human health is a common task for all mankind. Currently, development of drugs against the novel coronavirus (namely SARS-CoV-2) is quite urgent. Chinese medical workers and scientific researchers have found some drugs to play potential therapeutic effects on COVID-19 at the cellular level or in preliminary clinical trials. However, more fundamental studies and large sample clinical trials need to be done to ensure the efficacy and safety of these drugs. The adoption of these drugs without further testing must be careful. The relevant articles, news, and government reports published on the official and Preprint websites, PubMed and China National Knowledge Infrastructure (CNKI) databases from December 2019 to April 2020 were searched and manually filtered. The general pharmacological characteristics, indications, adverse reactions, general usage, and especially current status of the treatment of COVID-19 of those potentially effective drugs, including chemical drugs, traditional Chinese medicines (TCMs), and biological products in China were summarized in this review to guide reasonable medication and the development of specific drugs for the treatment of COVID-19.

Immuno-pathogenesis of nCOVID-19 and a possible host-directed therapy including anti-inflammatory and anti-viral prostaglandin (PG J2) for effective treatment and reduction in the death toll

Coronaviruses including severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, also known as 2019-nCoV especially in China) replicate and divide in host cells. During this they are partly hidden from the innate immune responses although inflammatory consequences of viral replication still occur. We propose that anti-inflammatory antiviral prostaglandins may not only restrict viral replication but also prevent inflammatory responses in the lungs and other vital organs that are known to be part of the immuno-pathogenesis of coronavirus disease-19 (COVID-19). The combination of anti-inflammatory antiviral prostaglandins with interferons may lead to the clearance of viruses inside growth-restricted infected cells. However, further experimental studies and clinical trials should be conducted to evaluate the safety and efficacy of these possible therapies.

Analysis of the susceptibility to COVID-19 in pregnancy and recommendations on potential drug screening

To analyze the susceptibility of SARS-CoV-2 in pregnancy and the drugs that can be used to treat pregnancy with COVID-19, so as to provide evidence for drug selection in clinic. By reviewing the existing literature, this paper analyzes the susceptibility of pregnant women to virus, especially to SARS-CoV-2, from the aspects of anatomical, reproductive endocrine and immune changes during pregnancy and screens effective and fetal-safe treatments from the existing drugs. The anatomical structure of the respiratory system is changed during pregnancy, and the virus transmitted by droplets and aerosols is more easily inhaled by pregnant women and is difficult to remove. Furthermore, the prognosis is worse after infection when compared with non-pregnancy women. And changes in reproductive hormones and immune systems during pregnancy collectively make them more susceptible to certain infections. More importantly, angiotensin-converting enzyme (ACE)-2, the SARS-CoV-2 receptor, has been proven highly increased during pregnancy, which may contribute to the susceptibility to SARS-CoV-2. When it comes to treatment, specific drugs for COVID-19 have not been found at present, and taking old drugs for new use in treating COVID-19 has become an emergency method for the pandemic. Particularly, drugs that show superior maternal and fetal safety are worthy of consideration for pregnant women with COVID-19, such as chloroquine, metformin, statins, lobinavir/ritonavir, glycyrrhizic acid, and nanoparticle-mediated drug delivery (NMDD), etc. Pregnant women are susceptible to COVID-19, and special attention should be paid to the selection of drugs that are both effective for maternal diseases and friendly to the fetus. However, there are still many deficiencies in the study of drug safety during pregnancy, and broad-spectrum, effective and fetal-safe drugs for pregnant women need to be developed so as to cope with more infectious diseases in the future.

Reducing mortality and morbidity in patients with severe COVID-19 disease by advancing ongoing trials of Mesenchymal Stromal (stem) Cell (MSC) therapy - Achieving global consensus and visibility for cellular host-directed therapies

As of May 17th 2020, the novel coronavirus disease 2019 (COVID-19) pandemic has caused 307,395 deaths worldwide, out of 3,917,366 cases reported to the World Health Organization. No specific treatments for reducing mortality or morbidity are yet available. Deaths from COVID-19 will continue to rise globally until effective and appropriate treatments and/or vaccines are found. In search of effective treatments, the global medical, scientific, pharma and funding communities have rapidly initiated over 500 COVID-19 clinical trials on a range of antiviral drug regimens and repurposed drugs in various combinations. A paradigm shift is underway from the current focus of drug development targeting the pathogen, to advancing cellular Host-Directed Therapies (HDTs) for tackling the aberrant host immune and inflammatory responses which underlie the pathogenesis of SARS-CoV-2 and high COVID-19 mortality rates. We focus this editorial specifically on the background to, and the rationale for, the use and evaluation of mesenchymal stromal (Stem) cells (MSCs) in treatment trials of patients with severe COVID-19 disease. Currently, the ClinicalTrials.gov and the WHO Clinical Trials Registry Platform (WHO ICTRP) report a combined 28 trials exploring the potential of MSCs or their products for treatment of COVID-19. MSCs should also be trialed for treatment of other circulating WHO priority Blueprint pathogens such as MERS-CoV which causes upto 34% mortality rates. It's about time funding agencies invested more into development MSCs per se, and also for a range of other HDTs, in combination with other therapeutic interventions. MSC therapy could turn out to be an important contribution to bringing an end to the high COVID-19 death rates and preventing long-term functional disability in those who survive disease.

Amphotericin B as antiviral drug: Possible efficacy against COVID-19

Since its discovery, amphotericin B (AmB) is still one of the most common first-line choices in treatment pulmonary mycoses for over seventh decades from discovery. AmB which is belonged to the polyene group has a wide spectrum in vitro and in vivo antimicrobial activity against fungi and parasites, resistance to AmB is rare despite extensive use. Recently, some studies focused on the potential antimicrobial action of AmB against some enveloped viruses such as human immunodeficiency virus, Japanese encephalitis virus, and rubella virus. Coronaviruses are enveloped positive-sense RNA nucleic acid viruses that have club-like spikes, characterized by a distinctive replication strategy; they are round and sometimes pleomorphic shapes. COVID-19 is regarding the new genera of coronaviridae that appear the first time in Wuhan, China, in early December 2019. Due to the continuous spreading of the novel COVID-19 with the exponential rise in death numbers, new therapeutic development is urgent, in general, there are no specific antiviral drugs or vaccines for 2019-novel coronavirus. Hence, this review may serve as an impetus for researchers working in the field of medical microbiology, vaccination, and antiviral drug design by discussion the most recent information about the antiviral action of AmB against COVID-19 infection as well as trying to a deep understanding of major properties, mechanisms of action, immune system responses, and antimicrobial efficiency of AmB. Since AmB is expected to alter the structure of the viral envelope, membrane integrity of cells, and internal cellular organelles, besides its other unique properties such as host immunomodulatory effects, so this review suggested that AmB as an effective anti-fungi drug thus may hold the promise of formulating a novel therapeutic option to treat COVID-19.

Middle East Respiratory Syndrome Coronavirus and Severe Acute Respiratory Syndrome Coronavirus

Emerging infectious diseases continue to be of a significant importance worldwide with the potential to cause major outbreaks and global pandemics. In 2002, the world had witnessed the appearance of the severe acute respiratory syndrome coronavirus in China which disappeared abruptly within 6 months. About a decade later, a new and emerging novel coronavirus named the Middle East respiratory syndrome coronavirus (MERS-CoV) was described in a patient from Saudi Arabia. These two coronaviruses shared multiple similarities in the epidemiology, clinical presentations, and posed challenges in its prevention and management. Seven years since its discovery, MERS-CoV continues to be a lethal zoonotic pathogen capable of causing severe pneumonia with high case fatality rates and the ability to cause large health care-associated outbreaks.

Successful treatment with plasma exchange followed by intravenous immunoglobulin in a critically ill patient with COVID-19

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Many severe COVID-19 patients require intensive care or even mechanical ventilation for those with respiratory failure.

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Clinical course of a COVID-19 patient with persistent diarrhoea, acute respiratory failure and shock 1 day after admission.

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The patient was undoubtedly classified into the severe type of COVID-19.

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Patient recovered promptly after plasma exchange (PE) followed by IVIg, without mechanical ventilation or intensive care.

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Timely initiation of PE followed by IVIg in severe COVID-19 patients may improve poor clinical outcomes of these patients.

Here we report a case of a laboratory-confirmed 2019 novel coronavirus (2019-nCoV)-infected patient with COVID-19 (coronavirus disease 2019) who developed respiratory failure and shock accompanied by persistent diarrhoea despite conventional therapeutic interventions. The patient avoided mechanical ventilation and showed an immediate clinical and radiological improvement following treatment with intensive plasma exchange (PE) followed by intravenous immunoglobulin (IVIG). Successful therapeutic strategies in this case suggest that timely initiation of PE treatment followed by IVIG in critically ill patients with COVID-19 may prevent the disease from worsening and help to reduce the requirement for mechanical ventilation and intensive supportive care. Moreover, it may improve poor clinical outcomes of these patients.

Middle East Respiratory Syndrome Coronavirus and the One Health concept

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is one of the major threats to the healthcare systems in some countries, especially in the Arabian Peninsula. MERS-CoV is considered an ideal example of the One Health concept. This is due to the animals, especially dromedary camels, play important roles in the transmission and sustainability of the virus, and the virus can be transmitted through aerosols of infected patients into the environment. However, there is some debate regarding the origin of MERS-CoV either from bats or other unknown reservoirs. The dromedary camel is the only identified animal reservoir to date. These animals play important roles in sustaining the virus in certain communities and may act as an amplifier of the virus by secreting it in their body fluids, especially in nasal and rectal discharges. MERS-CoV has been detected in the nasal and rectal secretions of infected camels, and MERS-CoV of this origin has full capacity to infect human airway epithelium in both in vitro and in vivo models. Other evidence confirms the direct transmission of MERS-CoV from camels to humans, though the role of camel meat and milk products has yet to be well studied. Human-to-human transmission is well documented through contact with an active infected patient or some silently infected persons. Furthermore, there are some significant risk factors of individuals in close contact with a positive MERS-CoV patient, including sleeping in the same patient room, removing patient waste (urine, stool, and sputum), and touching respiratory secretions from the index case. Outbreaks within family clusters have been reported, whereby some blood relative patients were infected through their wives in the same house were not infected. Some predisposing genetic factors favor MERS-CoV infection in some patients, which is worth investigating in the near future. The presence of other comorbidities may be another factor. Overall, there are many unknown/confirmed aspects of the virus/human/animal network. Here, the most recent advances in this context are discussed, and the possible reasons behind the emergence and sustainability of MERS-CoV in certain regions are presented. Identification of the exact mechanism of transmission of MERS-CoV from camels to humans and searching for new reservoir/s are of high priority. This will reduce the shedding of the virus into the environment, and thus the risk of human infection can be mitigated.

MERS-CoV: Understanding the Latest Human Coronavirus Threat

Human coronaviruses cause both upper and lower respiratory tract infections in humans. In 2012, a sixth human coronavirus (hCoV) was isolated from a patient presenting with severe respiratory illness. The 60-year-old man died as a result of renal and respiratory failure after admission to a hospital in Jeddah, Saudi Arabia. The aetiological agent was eventually identified as a coronavirus and designated Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV has now been reported in more than 27 countries across the Middle East, Europe, North Africa and Asia. As of July 2017, 2040 MERS-CoV laboratory confirmed cases, resulting in 712 deaths, were reported globally, with a majority of these cases from the Arabian Peninsula. This review summarises the current understanding of MERS-CoV, with special reference to the (i) genome structure; (ii) clinical features; (iii) diagnosis of infection; and (iv) treatment and vaccine development.

The Middle East Respiratory Syndrome Coronavirus - A Continuing Risk to Global Health Security

Two new zoonotic coronaviruses causing disease in humans (Zumla et al. 2015a; Hui and Zumla 2015; Peiris et al. 2003; Yu et al. 2014) have been the focus of international attention for the past 14 years due to their epidemic potential; (1) The Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) (Peiris et al. 2003) first discovered in China in 2001 caused a major global epidemic of the Severe Acute Respiratory Syndrome (SARS). (2) The Middle East respiratory syndrome coronavirus (MERS-CoV) is a new corona virus isolated for the first time in a patients who died of severe lower respiratory tract infection in Jeddah (Saudi Arabia) in June 2012 (Zaki et al. 2012). The disease has been named Middle East Respiratory Syndrome (MERS) and it has remained on the radar of global public health authorities because of recurrent nosocomial and community outbreaks, and its association with severe disease and high mortality rates (Assiri et al. 2013a; Al-Abdallat et al. 2014; Memish et al. 2013a; Oboho et al. 2015; The WHO MERS-CoV Research Group 2013; Cotten et al. 2013a; Assiri et al. 2013b; Memish et al. 2013b; Azhar et al. 2014; Kim et al. 2015; Wang et al. 2015; Hui et al. 2015a). Cases of MERS have been reported from all continents and have been linked with travel to the Middle East (Hui et al. 2015a; WHO 2015c). The World Health Organization (WHO) have held nine meetings of the Emergency Committee (EC) convened by the Director-General under the International Health Regulations (IHR 2005) regarding MERS-CoV (WHO 2015c). There is wishful anticipation in the political and scientific communities that MERS-CoV like SARS-CoV will disappear with time. However it’s been nearly 4 years since the first discovery of MERS-CoV, and MERS cases continue to be reported throughout the year from the Middle East (WHO 2015c). There is a large MERS-CoV camel reservoir, and there is no specific treatment or vaccine (Zumla et al. 2015a). With 10 million people visiting Saudi Arabia every year for Umrah and/or Hajj, the potential risk of global spread is ever present (Memish et al. 2014a; McCloskey et al. 2014; Al-Tawfiq et al. 2014a).

The enemy within: Targeting host-parasite interaction for antileishmanial drug discovery

The state of antileishmanial chemotherapy is strongly compromised by the emergence of drug-resistant Leishmania. The evolution of drug-resistant phenotypes has been linked to the parasites’ intrinsic genome instability, with frequent gene and chromosome amplifications causing fitness gains that are directly selected by environmental factors, including the presence of antileishmanial drugs. Thus, even though the unique eukaryotic biology of Leishmania and its dependence on parasite-specific virulence factors provide valid opportunities for chemotherapeutical intervention, all strategies that target the parasite in a direct fashion are likely prone to select for resistance. Here, we review the current state of antileishmanial chemotherapy and discuss the limitations of ongoing drug discovery efforts. We finally propose new strategies that target Leishmania viability indirectly via mechanisms of host–parasite interaction, including parasite-released ectokinases and host epigenetic regulation, which modulate host cell signaling and transcriptional regulation, respectively, to establish permissive conditions for intracellular Leishmania survival.

Middle East Respiratory Syndrome

Between September 2012 and January 20, 2017, the World Health Organization (WHO) received reports from 27 countries of 1879 laboratory-confirmed cases in humans of the Middle East respiratory syndrome (MERS) caused by infection with the MERS coronavirus (MERS-CoV) and at least 659 related deaths. Cases of MERS-CoV infection continue to occur, including sporadic zoonotic infections in humans across the Arabian Peninsula, occasional importations and associated clusters in other regions, and outbreaks of nonsustained human-to-human transmission in health care settings. Dromedary camels are considered to be the most likely source of animal-to-human transmission. MERS-CoV enters host cells after binding the dipeptidyl peptidase 4 (DPP-4) receptor and the carcinoembryonic antigen–related cell-adhesion molecule 5 (CEACAM5) cofactor ligand, and it replicates efficiently in the human respiratory epithelium. Illness begins after an incubation period of 2 to 14 days and frequently results in hypoxemic respiratory failure and the need for multiorgan support. However, asymptomatic and mild cases also occur. Real-time reverse-transcription–polymerase-chain-reaction (RT-PCR) testing of respiratory secretions is the mainstay for diagnosis, and samples from the lower respiratory tract have the greatest yield among seriously ill patients. There is no antiviral therapy of proven efficacy, and thus treatment remains largely supportive; potential vaccines are at an early developmental stage. There are multiple gaps in knowledge regarding the evolution and transmission of the virus, disease pathogenesis, treatment, and prospects for a vaccine. The ongoing occurrence of MERS in humans and the associated high mortality call for a continued collaborative approach toward gaining a better understanding of the infection both in humans and in animals. MERS-CoV was first identified in September 2012 in a patient from Saudi Arabia who had hypoxemic respiratory failure and multiorgan illness. Subsequent cases have included infections in humans across the Arabian Peninsula, occasional importations and associated clusters in other regions, and outbreaks of nonsustained human-to-human transmission in health care settings (Fig. 1).

Pharmacologic Inhibition of Host Phosphodiesterase-4 Improves Isoniazid-Mediated Clearance of Mycobacterium tuberculosis

The lengthy duration of multidrug therapy needed to cure tuberculosis (TB) poses significant challenges for global control of the disease. Moreover, chronic inflammation associated with TB leads to pulmonary damage that can remain even after successful cure. Thus, there is a great need for the development of effective shorter drug regimens to improve clinical outcome and strengthen TB control. Host-directed therapy (HDT) is emerging as a novel adjunctive strategy to enhance the efficacy and shorten the duration of TB treatment. Previously, we showed that the administration of CC-3052, a phosphodiesterase-4 inhibitor (PDE4i), reduced the host inflammatory response during Mycobacterium tuberculosis (Mtb) infection and improved the antimicrobial efficacy of isoniazid (INH) in both the mouse and rabbit models. In the present study, we evaluated the pharmacokinetics and explored the mechanism underlying the efficacy of a more potent PDE4i, CC-11050, as adjunct to INH treatment in a mouse model of pulmonary Mtb infection. Genome-wide lung transcriptome analysis confirmed the dampening of inflammation and associated network genes that we previously reported with CC-3052. Consistent with the reduction in inflammation, a significant improvement in Mtb control and pathology was observed in the lungs of mice treated with CC-11050 plus INH, compared to INH alone. This important confirmatory study will be used to help design upcoming human clinical trials with CC-11050 as an HDT for TB treatment.

Nitazoxanide, a new drug candidate for the treatment of Middle East respiratory syndrome coronavirus

Nitazoxanide is a broad-spectrum antiviral agent undergoing clinical development for treatment of influenza and other viral respiratory infections. Nitazoxanide exhibits in vitro activity against Middle East respiratory syndrome coronavirus (MERS-CoV) and other coronaviruses, inhibiting expression of the viral N protein. Nitazoxanide also suppresses production of pro-inflammatory cytokines in peripheral blood mononuclear cells and suppresses interleukin 6 production in mice. Having been used extensively in clinical trials and in post-marketing experience, nitazoxanide is an attractive drug candidate for treatment of Middle East respiratory syndrome. Future research should include in vitro mechanism studies, animal models of MERS-CoV infection, clinical trials, including dose-ranging trials, and evaluation of combination therapy with other potential MERS-CoV antivirals.

Critically ill patients with Middle East respiratory syndrome coronavirus infection

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency medicine 2016. Other selected articles can be found online at http://www.biomedcentral.com/collections/annualupdate2016. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901.

Coronaviruses and the human airway: a universal system for virus-host interaction studies

Human coronaviruses (HCoVs) are large RNA viruses that infect the human respiratory tract. The emergence of both Severe Acute Respiratory Syndrome and Middle East Respiratory syndrome CoVs as well as the yearly circulation of four common CoVs highlights the importance of elucidating the different mechanisms employed by these viruses to evade the host immune response, determine their tropism and identify antiviral compounds. Various animal models have been established to investigate HCoV infection, including mice and non-human primates. To establish a link between the research conducted in animal models and humans, an organotypic human airway culture system, that recapitulates the human airway epithelium, has been developed. Currently, different cell culture systems are available to recapitulate the human airways, including the Air-Liquid Interface (ALI) human airway epithelium (HAE) model. Tracheobronchial HAE cultures recapitulate the primary entry point of human respiratory viruses while the alveolar model allows for elucidation of mechanisms involved in viral infection and pathogenesis in the alveoli. These organotypic human airway cultures represent a universal platform to study respiratory virus-host interaction by offering more detailed insights compared to cell lines. Additionally, the epidemic potential of this virus family highlights the need for both vaccines and antivirals. No commercial vaccine is available but various effective antivirals have been identified, some with potential for human treatment. These morphological airway cultures are also well suited for the identification of antivirals, evaluation of compound toxicity and viral inhibition.

Critically Ill Patients with Middle East Respiratory Syndrome Coronavirus Infection

The Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging virus that may lead to severe acute respiratory illness frequently associated with multiorgan failure and death. The objective of this chapter is to summarize the current state of knowledge regarding the pathogenesis, clinical manifestations, diagnosis, management and outcomes of MERS-CoV infection focusing on the critically ill.