Chloroquine and hydroxychloroquine to treat COVID-19: between hope and caution

Hypertension related toxicity of chloroquine explains its failure against COVID-19: Based on rat model

Chloroquine was once thought to be a promising treatment for COVID-19 but it quickly failed due to its inefficiency and association with increased mortality. Further, comorbidities such as hypertension may have contributed this failure. The safety and toxicity of chloroquine at doses required for treating SARS-CoV-2 infection in hypertensive patients remain unknown. Herein, to investigate these effects, we performed a safety evaluation of chloroquine at the approved dose (63 mg/kg) and at a high dose (126 mg/kg) in hypertensive rats. We found that chloroquine increased the mortality of hypertensive rats to 18.2% and 100%, respectively, after 7 days. During the chloroquine exposure period, the bodyweight, feed, and water consumption of hypertensive rats were decreased significantly. In addition, we show that chloroquine induces prolongation of QTc interval, elevation of LDH and CK, and histopathological damage of the myocardium in hypertensive rats. Ocular toxicity was observed in hypertensive rats in the form of hemorrhage in the eyes and retinal damage. Furthermore, we also observed intestinal toxicity in hypertensive rats, which presented as thinning intestinal walls with hemorrhagic contents, and histopathological changes of the jejunum. Hepatotoxicity was also evidenced by elevated ALT, and vacuolization of hepatocytes was also observed. Nephrotoxicity was observed only in high dose chloroquine-treated hypertensive rats, presenting as alterations of urinalysis and renal function. Immune alterations were also found in high-dose chloroquine-treated hypertensive rats with elevation of serum IL-10, IL-1β and GRO, and moderate damage to the spleen. In summary, this study partially explains the reason for the failure of chloroquine as a COVID-19 therapy, and underlines the importance of safety evaluation and medical supervision of chloroquine to avoid patient harm, especially to those with hypertension.

Safety considerations of chloroquine in the treatment of patients with diabetes and COVID-19

Patients with underlying diseases and coronavirus disease 2019 (COVID-19) are at increased risk of death. Using the recommended anti-COVID-19 drug, chloroquine phosphate (CQ), to treat patients with severe cases and type 2 diabetes (T2D) could potentially cause harm. We aimed to understand the safety of CQ in patients with T2D by administrating the recommended dose (63 mg/kg twice daily for 7 days) and a high dose (126 mg/kg twice daily for 7 days) of CQ in T2D rats. We found that CQ increased the total mortality of the T2D rats from 27.3% to 72.7% in the recommended and high-dose groups during the whole period. CQ also induced hematotoxicity of T2D rats in the high-dose group; the hepatic enzymes in T2D rats were significantly elevated. CQ also changed the electrocardiograms, prolonged the QTc intervals, and produced urinary leukocytes and proteins in the T2D rats. Histopathological observations revealed that CQ caused severe damage to the rats' heart, jejunum, liver, kidneys, spleen, and retinas. Furthermore, CQ significantly decreased the serum IL-1β and IL-6 levels. In conclusion, the CQ dosage and regimen used to treat COVID-19 induced adverse effects in diabetic rats, suggesting the need to reevaluate the effective dose of CQ in humans.

Clinical data mining reveals Gancao-Banxia as a potential herbal pair against moderate COVID-19 by dual binding to IL-6/STAT3

BACKGROUND

Coronavirus disease 2019 (COVID-19) keeps spreading globally. Chinese medicine (CM) exerts a critical role for the prevention or therapy of COVID-19 in an integrative and holistic way. However, mining and development of early, efficient, multisite binding CMs that inhibit the cytokine storm are imminent.

METHODS

The formulae were extracted retrospectively from clinical records in Hunan Province. Clinical data mining analysis and association rule analysis were employed for mining the high-frequency herbal pairs and groups from formulae. Network pharmacology methods were applied to initially explore the most critical pair's hub targets, active ingredients, and potential mechanisms. The binding power of active ingredients to the hub targets was verified by molecular docking.

RESULTS

Eight hundred sixty-two prescriptions were obtained from 320 moderate COVID-19 through the Hunan Provincial Health Commission. Glycyrrhizae Radix et Rhizoma (Gancao) and Pinelliae Rhizoma (Banxia) were used with the highest frequency and support. There were 49 potential genes associated with Gancao-Banxia pair against moderate COVID-19 patients. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that Gancao-Banxia might act via inflammatory response, viral defense, and immune responses signaling pathways. IL-6 and STAT3 were the two most hub targets in the protein-protein interaction (PPI) network. The binding of five active ingredients originated from Gancao-Banxia to IL-6-STAT3 was verified by molecular docking, namely quercetin, coniferin, licochalcone a, Licoagrocarpin and (3S,6S)-3-(benzyl)-6-(4-hydroxybenzyl)piperazine-2,5-quinone, maximizing therapeutic efficacy.

CONCLUSIONS

This work provided some potential candidate Chinese medicine formulas for moderate COVID-19. Among them, Gancao-Banxia was considered the most potential herbal pair. Bioinformatic data demonstrated that Gancao-Banxia pair may achieve dual inhibition of IL-6-STAT3 via directly interacting with IL-6 and STAT3, suppressing the IL-6 amplifier. SARS-CoV-2 models will be needed to validate this possibility in the future.

Design, Synthesis, and Development of 4‐[(7‐Chloroquinoline‐4‐yl)amino]phenol as a Potential SARS‐CoV‐2 Mpro Inhibitor

A series of chloroquine analogs were designed to search for a less toxic chloroquine derivative as a potential SARS‐CoV‐2 Mpro inhibitor. Herein, an ANN‐based QSAR model was built to predict the IC₅₀ values of each analog using the experimental values of other 4‐aminoquinolines as the training set. Subsequently, molecular docking was used to evaluate each analog's binding affinity to Mpro. The analog that showed the greatest affinity and lowest IC₅₀ values was synthesized and characterized for its posterior incorporation into a polycaprolactone‐based nanoparticulate system. After characterizing the loaded nanoparticles, an in vitro drug release assay was carried out, and the cytotoxicity of the analog and loaded nanoparticles was evaluated using murine fibroblast (L929) and human lung adenocarcinoma (A549) cell lines. Results show that the synthesized analog is much less toxic than chloroquine and that the nanoparticulate system allowed for the prolonged release of the analog without evidence of adverse effects on the cell lines used; therefore, suggesting that the analog could be a potential therapeutic option for COVID‐19.

COVID-19 pandemic: Can zinc supplementation provide an additional shield against the infection?

Coronavirus disease-19 (COVID-19)-induced severe acute respiratory syndrome is a global pandemic. As a preventive measure, human movement is restricted in most of the world. The Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), along with the World Health Organization (WHO) have laid out some therapeutic guidelines for the infected patients. However, other than handwashing and vigilance surrounding commonly encountered oronasal symptoms and fever, no universally available prophylactic measure has yet been established. In a pandemic, the accessibility of a prophylactic biologically active substance is crucial. Ideally, it would be something readily available at a low price to a larger percentage of the population with minimal risk. Studies have demonstrated that zinc may reduce viral replication and increase immune responses. While consuming zinc (within the recommended upper safety limits), as a prophylactic might provide an additional shield against the initiation and progression of COVID-19 would need clinical studies, the potential clearly exists. Even after vaccination, low zinc status may affect the vaccination responses.

Assessment of self-medication practices in the context of the COVID-19 outbreak in Togo

BACKGROUND

To date, there is no effective treatment for COVID-19, which is a pandemic disease, caused by a novel coronavirus called SARS-CoV-2. In Togo, where four in five people practice self-medication, the absence of a cure for COVID-19 and the constant progression of the disease requires an assessment of self-medication patterns in the context of the pandemic. This study aimed to estimate the prevalence of self-medication to prevent COVID-19 and its associated factors in Lomé, Togo.

METHODS

A cross-sectional study was conducted in Lomé, the capital city of Togo, from April 23rd to May 8th, 2020, with a sample of participants from five sectors: the healthcare, air transport, police, road transport and informal sectors. The participants were invited to provide information about their self-medication practices to prevent COVID-19 in the 2 weeks preceding the survey.

RESULTS

A total of 955 participants (71.6% men) with a median age of 36 (IQR 32-43) were included. Approximately 22.1% were in the air transport sector, 20.5% were in the police sector, and 38.7% were in the health sector. The overall prevalence of self-medication to prevent COVID-19 was 34.2% (95% CI: 31.2-37.3%). The most commonly used products were vitamin C (27.6%) and traditional medicine (10.2%). Only 2.0% of participants reported using chloroquine/hydroxychloroquine. Female sex (aOR=1.90; p< 0.001), work in the health sector (aOR=1.89; p= 0.001), secondary education level (aOR= 2.28; p= 0.043) and university education level (aOR= 5.11; p< 0.001) were associated with self-medication.

CONCLUSION

One-third of the individuals in high-risk populations in Lomé practiced self-medication. Intensifying awareness campaigns is crucial to fight misinformation about alleged COVID-19 prevention products on social media.

Pharmacological insight into potential therapeutic agents for the deadly Covid-19 pandemic

Coronaviruses are pleomorphic, enveloped, or spherical viruses, which have a size ranging from 80 to 120 nm. These viruses act on receptors that cause the triggering of fusion. Coronaviruses were first described after cultivation from patients with common colds by Tyrell and Bynoe in 1966. There are various subtypes of coronavirus, 7 out of these can cause infection in human beings. The Alpha subtype is responsible for mild infection showing symptoms or infection without any prevailing symptoms. On the other hand, the beta subtype is responsible for very serious diseases leading to fatality. The lineage of this novel SARS-CoV-2 falls under the beta lineage of the beta coronavirus which has been observed to have a relation to the MERS and SARS coronavirus. In the Huanan market selling seafood, the transition of this novel virus in humans from animals has occurred. It has the potential to be the cause of widespread fatality amongst the people of the globe. On August 16, 2020, the World Health Organisation had reported 2,1294,845 cases which are confirmed to date out of which 413,372 deaths have occurred. Currently, no targeted antiviral vaccines or drugs to fight against COVID-19 infection have been approved for use in humans. This pandemic is fast emerging and drug repurposing is the only ray of hope which can ensure quick availability. Vaccine development is progressing each day with various platforms such as DNA, Live Attenuated Virus, Non-Replicating Viral Vector, Protein Subunit, and RNA, being utilized for the development. COVID-19 attacks the immune system of the host & this can result in a cytokine storm. As a result, various herbal agents both acting as antivirals and immunomodulatory can also be used. Convalescent Plasma Therapy and Mesenchymal Stem Cell therapy are also being explored as a plausible therapeutic. There remains a considerable unmet need for therapeutics to be addressed. The development and availability of accessible and efficient therapy are essential for the treatment of patients. This review discusses the epidemiology, pathogenesis, the tale of origin, and transmission of COVID-19 or Sars-Cov2 virus and gives evidence of potential therapeutic agents that can be explored to cast away this pandemic.

Impact of Trump's Promotion of Unproven COVID-19 Treatments and Subsequent Internet Trends: Observational Study

BACKGROUND

Individuals with large followings can influence public opinions and behaviors, especially during a pandemic. In the early days of the pandemic, US president Donald J Trump has endorsed the use of unproven therapies. Subsequently, a death attributed to the wrongful ingestion of a chloroquine-containing compound occurred.

OBJECTIVE

We investigated Donald J Trump's speeches and Twitter posts, as well as Google searches and Amazon purchases, and television airtime for mentions of hydroxychloroquine, chloroquine, azithromycin, and remdesivir.

METHODS

Twitter sourcing was catalogued with Factba.se, and analytics data, both past and present, were analyzed with Tweet Binder to assess average analytics data on key metrics. Donald J Trump's time spent discussing unverified treatments on the United States' 5 largest TV stations was catalogued with the Global Database of Events, Language, and Tone, and his speech transcripts were obtained from White House briefings. Google searches and shopping trends were analyzed with Google Trends. Amazon purchases were assessed using Helium 10 software.

RESULTS

From March 1 to April 30, 2020, Donald J Trump made 11 tweets about unproven therapies and mentioned these therapies 65 times in White House briefings, especially touting hydroxychloroquine and chloroquine. These tweets had an impression reach of 300% above Donald J Trump's average. Following these tweets, at least 2% of airtime on conservative networks for treatment modalities like azithromycin and continuous mentions of such treatments were observed on stations like Fox News. Google searches and purchases increased following his first press conference on March 19, 2020, and increased again following his tweets on March 21, 2020. The same is true for medications on Amazon, with purchases for medicine substitutes, such as hydroxychloroquine, increasing by 200%.

CONCLUSIONS

Individuals in positions of power can sway public purchasing, resulting in undesired effects when the individuals' claims are unverified. Public health officials must work to dissuade the use of unproven treatments for COVID-19.

A Patient with COVID-19 Disease in a Referral Hospital in Iran: A Typical Case

After the initial outbreak of the new Coronavirus in Wuhan at the end of December 2019, many new cases were reported in other provinces of China and also many other countries over the world, including South Korea, Italy, Iran, Japan, and 68 other countries. We present a case report of a 61-year-old woman with a history of diabetes mellitus who was referred to the emergency department of a referral hospital in Tehran, Iran. The patient presented with fever, chills, and myalgia within three days. Laboratory analysis showed increased levels of erythrocyte sedimentation rate (ESR), and mild leukopenia. SARS-CoV-2 PCR test -under the Iran Ministry of Health and Medical Education (MoH&ME) guidelines- was conducted and the result was positive. The chest X-ray showed bilateral ground-glass opacity. O2 saturation was 87% (without O2 therapy). The patient was hospitalized and treated with Oseltamivir 75 mg every 12 hours, Lopinavir/Ritonavir (Kaletra) 400/100 mg every 12 hours and hydroxychloroquine 400 mg stat. The patient's last O2 saturation measured was 93% and she had no fever on the 10th day of hospitalization. Therefore, she was discharged from hospital and quarantined at home according to the Iran Ministry of Health protocol.

Hydroxychloroquine and Chloroquine in Prophylaxis and Treatment of COVID-19: What Is Known?

The corona virus disease-19 (COVID-19) pandemic has affected the entire world causing huge economic losses and considerable morbidity and mortality. Considering the explosive growth of the pandemic repurposing existing medicines may be cost-effective and may be approved for use in COVID-19 faster. Researchers and medical practitioners worldwide have explored the use of chloroquine and hydroxychloroquine, in few occasions combined with the macrolide antibiotic azithromycin, for COVID-19 treatment. These two drugs are economic and easily available, and hence gained attention as a potential option for COVID-19 management. As per the available evidence, the outcomes of treatments with these medications are conflicting from both the efficacy and safety (predominantly cardiac related) perspectives. Currently, multiple studies are underway to test the safety and efficacy of these medications and more results are expected in the near future. The retina, the endocrine system (with risk of hypoglycemia), the musculoskeletal system, the hematological system, and the neurological system may also be affected. The use of these drugs is contraindicated in patients with arrhythmias, known hypersensitivity, and in patients on amiodarone. In addition to the published literature, personal communication with doctors treating COVID-19 patients seems to suggest the drugs may be effective in reducing symptoms and hastening clinical recovery. The literature evidence is still equivocal and further results are awaited. There has been recent controversy including retraction of articles published in prestigious journals about these medicines. Their low cost, long history of use, and easy availability are positive factors with regard to use of these drugs in COVID-19.

Gut Microbiota Dysbiosis-Immune Hyperresponse-Inflammation Triad in Coronavirus Disease 2019 (COVID-19): Impact of Pharmacological and Nutraceutical Approaches

Coronavirus Disease 2019 (COVID-19) is a pandemic infection caused by a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients present a complex clinical picture that, in severe cases, evolves to respiratory, hepatic, gastrointestinal, and neurological complications, and eventually death. The underlying pathophysiological mechanisms are complex and multifactorial and have been summarized as a hyperresponse of the immune system that originates an inflammatory/cytokine storm. In elderly patients, particularly in those with pre-existing cardiovascular, metabolic, renal, and pulmonary disorders, the disease is particularly severe, causing prolonged hospitalization at intensive care units (ICU) and an increased mortality rate. Curiously, the same populations have been described as more prone to a gut microbiota (GM) dysbiosis profile. Intestinal microflora plays a major role in many metabolic and immune functions of the host, including to educate and strengthen the immune system to fight infections, namely of viral origin. Notably, recent studies suggest the existence of GM dysbiosis in COVID-19 patients. This review article highlights the interplay between the triad GM dysbiosis-immune hyperresponse-inflammation in the individual resilience/fragility to SARS-CoV-2 infection and presents the putative impact of pharmacological and nutraceutical approaches on the triumvirate, with focus on GM.

Chloroquine against malaria, cancers and viral diseases

Quinoline (QN) derivatives are often used for the prophylaxis and treatment of malaria. Chloroquine (CQ), a protonated, weakly basic drug, exerts its antimalarial effect mainly by increasing pH and accumulating in the food vacuole of the parasites. Repurposing CQ is an emerging strategy for new indications. Given the inhibition of autophagy and its immunomodulatory action, CQ shows positive efficacy against cancer and viral diseases, including Coronavirus 2019 (COVID-19). Here, we review the underlying mechanisms behind the antimalarial, anticancer and antiviral effects of CQ. We also discuss the clinical evidence for the use of CQ and hydroxychloroquine (HCQ) against COVID-19.

The clinical benefits of Chinese patent medicines against COVID-19 based on current evidence

The outbreak of emerging infectious pneumonia caused by 2019 Novel Coronavirus (2019-nCoV) has posed an enormous threat to public health, and traditional Chinese medicine (TCM) have made vast contribution to the prevention, treatment and rehabilitation of coronavirus disease 19 (COVID-19) among Chinese population. As an indispensable part of TCM, Chinese patent medicines (CPMs) are highly valued and critically acclaimed in their campaign to contain and tackle the epidemic, they can achieve considerable effects for both suspected cases under medical observation period, and confirmed individuals with serious underlying diseases or critical conditions. Given this, based on the Guideline on Diagnosis and Treatment of Coronavirus Disease 2019 in China, the present review summarized the basic information, clinical evidence and published literatures of recommended CPMs against COVID-19. The details were thoroughly introduced involving compositions, therapeutic effects, clinical indications, medication history of CPMs and the profiles of corresponding research. With regard to infected patients with different stages and syndrome, the preferable potentials and therapeutic mechanism of CPMs were addressed through the comprehensive collection of relevant literatures and on-going clinical trials. This study could provide an insight into clinical application and underlying mechanism of recommended CPMs against COVID-19, with the aim to share the Chinese experience in clinical practice and facilitate scientific development of TCM, especially CPMs in the fierce battle of COVID-19.

Global Pandemic Conditions and List of Possible Medications and Vaccines for the Treatment of COVID-19: A Review

At the end of December 2019, a novel coronavirus was identified which caused severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with a disease known as coronavirus disease 2019 (COVID-19). The virus first originated in the city of Wuhan in China, causing symptoms such as pneumonic plague, which began in the Wuhan and then spread throughout the world with high transmission efficiency. Special precautions and care are needed such as leaving the public area, covering your mouth with a mask, not shaking hands, washing hands, and sanitation from time to time. Infection due to SARS-CoV-2 shows several symptoms, one of which is very often the patient shows difficulty breathing. Currently, COVID-19 has been declared a global pandemic and has almost attacked all countries in the world, including in India which has one of the largest human populations in the entire world. One of the challenges in handling COVID-19 is the unavailability of drugs or special vaccines to treat the disease, so clinical practitioners and academics are currently testing various drugs to see how they affect the COVID-19 patients. Some of the drugs tested provide effective mechanisms against SARS-CoV-2, such as chloroquine, remdesivir, lopinavir, and vaccines under development. These drugs are still being tested and are now at the forefront to combat the effects of SARS-CoV-2 infection. This review article will discuss all kinds of ins and outs of SARS-CoV-2 and COVID-19, including the transmission method, how to prevent it, as well as various drugs and vaccines currently used in handling COVID-19.

Case Report: Hepatotoxicity Associated with the Use of Hydroxychloroquine in a Patient with COVID-19

Hydroxychloroquine (HCQ) has been used for the treatment of novel coronavirus disease (COVID-19) cases. However, evidence of efficacy remains limited, and adverse events can be associated with its use. Here, we report a case of a patient with severe COVID-19 who, after being administered HCQ, exhibited a 10-fold increase in serum levels of transaminases, followed by a rapid decrease after HCQ was withdrawn. Considering the significantly increased use of HCQ during the COVID-19 pandemic, this case alerts us to the potential for HCQ to be associated with hepatotoxicity and the need to monitor liver function during HCQ therapy.

Structure-based drug designing for potential antiviral activity of selected natural products from Ayurveda against SARS-CoV-2 spike glycoprotein and its cellular receptor

The recent outbreak of COVID-19 caused by SARS-CoV-2 brought a great global public health and economic concern. SARS-CoV-2 is an enveloped RNA virus, from the genus Betacoronavirus. Although few molecules have been tested and shown some efficacy against SARS-CoV-2 in humans but a safe and cost-effective attachment inhibitors are still required for the treatment of COVID-19. Natural products are gaining attention because of the large therapeutic window and potent antiviral, immunomodulatory, anti-inflammatory, and antioxidant properties. Therefore, this study was planned to screen natural products from Ayurveda that have the potential to modulate host immune system as well as block the virus entry in host cells by interfering its interaction with cellular receptor and may be used to develop an effective and broad-spectrum strategy for the management of COVID-19 as well as other coronavirus infections in coming future. To decipher the antiviral activity of the selected natural products, molecular docking was performed. Further, the drug-likeness, pharmacokinetics and toxicity parameters of the selected natural products were determined. Docking results suggest that curcumin and nimbin exhibits highest interaction with spike glycoprotein (MolDock score - 141.36 and - 148.621 kcal/mole) and ACE2 receptor (MolDock score - 142.647 and - 140.108 kcal/mole) as compared with other selected natural products/drugs and controls. Also, the pharmacokinetics data illustrated that all selected natural products have better pharmacological properties (low molecular weight; no violation of Lipinski rule of five, good absorption profiles, oral bioavailability, good blood-brain barrier penetration, and low toxicity risk). Our study exhibited that curcumin, nimbin, withaferin A, piperine, mangiferin, thebaine, berberine, and andrographolide have significant binding affinity towards spike glycoprotein of SARS-CoV-2 and ACE2 receptor and may be useful as a therapeutic and/or prophylactic agent for restricting viral attachment to the host cells. However, few other natural products like resveratrol, quercetin, luteolin, naringenin, zingiberene, and gallic acid has the significant binding affinity towards ACE2 receptor only and therefore may be used for ACE2-mediated attachment inhibition of SARS-CoV-2.

Pentoxifylline: An Immunomodulatory Drug for the Treatment of COVID-19

Rapidly spreading outbreak of the novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is causing serious health concerns worldwide. It started as an epidemic in Wuhan, Hubei province, central China, and has now become a pandemic, spreading over most of the continents of the planet. The major clinical symptoms of the infection are dry cough, fever, pneumonia, respiratory failure, hypoxia, and in certain cases, even death. Alveolar damage and respiratory system failure are observed in severe cases. Initial mild infection leads to activation of the immune system in the lungs and accumulation of various inflammatory cells and molecules. At a later phase during the infection, a “cytokine storm” causes an Acute Respiratory Distress Syndrome (ARDS), leading to an increase in the production of pro-inflammatory cytokines, migration of a large number of immune cells to the site of infection, and ultimately pulmonary damage. The rapid and uncontrolled outbreak requires putative therapeutic drugs for treatment of patients suffering from COVID-19. Amongst the currently used antiviral drugs, such as hydroxychloroquine, lopinavir, remdesivir etc. we would like to present an update on another effective drug, pentoxifylline. Pentoxifylline has anti-inflammatory, immunomodulatory, anti-viral, and bronchodilatory properties. Pentoxifylline is known to reduce cytokine production, immune cell migration, and suppress certain signal transduction pathways (e.g. NF-κβ and STAT3). Thus, it minimizes inflammatory damage in the lung tissues.

Novel Coronavirus-Induced Right Ventricular Failure and Point of Care Echocardiography: A Case Report

Various cardiovascular complications have been reported in patients with coronavirus disease 2019. Common complications include acute myocardial injury, myocarditis, arrhythmia, pericarditis, heart failure, and shock. We present a case of cor pulmonale diagnosed with serial point of care ultrasound. Given the current shortage of personal protective equipment (PPE) and high infectivity of this virus, we acknowledge the utility of this tool in obtaining important clinical information while minimizing exposure and PPE consumption.

COVID-19 compared to other epidemic coronavirus diseases and the flu

Coronaviruses are among the largest group of known positive - sense RNA viruses with a wide range of animal hosts as reservoir. In the last two decades, newly evolved coronaviruses such as the severe acute respiratory syndrome coronavirus (SARS-CoV) which caused the infamous 2002 outbreak, the Middle East respiratory syndrome coronavirus (MERS-CoV) which caused an outbreak in 2012, and now the SARS-CoV-2 [responsible for the current coronavirus disease 2019 (COVID-19)] have all posed notable threats to global public health. But, how does the current COVID-19 outbreak compare with previous coronaviruses diseases? In this review, we look at the key differences between SARS-CoV, MERS-CoV, and SARS-CoV-2, and examine challenges in determining accurate estimates of the severity of COVID-19. We discuss coronavirus outbreaks in light of key outbreak severity indicators including, disease fatality, pathogen novelty, ease of transmission, geographical range, and outbreak preparedness. Finally, we review clinical trials of emerging treatment modalities and provide recommendations on the control of COVID-19 based on the mode of transmission of the coronaviruses. We also recommend the development and use of a standardized predictive epidemic severity models to inform future epidemic response.

Anti-malarial drug, artemisinin and its derivatives for the treatment of respiratory diseases

Artemisinins are sesquiterpene lactones with a peroxide moiety that are isolated from the herb Artemisia annua. It has been used for centuries for the treatment of fever and chills, and has been recently approved for the treatment of malaria due to its endoperoxidase properties. Progressively, research has found that artemisinins displayed multiple pharmacological actions against inflammation, viral infections, and cell and tumour proliferation, making it effective against diseases. Moreover, it has displayed a relatively safe toxicity profile. The use of artemisinins against different respiratory diseases has been investigated in lung cancer models and inflammatory-driven respiratory disorders. These studies revealed the ability of artemisinins in attenuating proliferation, inflammation, invasion, and metastasis, and in inducing apoptosis. Artemisinins can regulate the expression of pro-inflammatory cytokines, nuclear factor-kappa B (NF-κB), matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), promote cell cycle arrest, drive reactive oxygen species (ROS) production and induce Bak or Bax-dependent or independent apoptosis. In this review, we aim to provide a comprehensive update of the current knowledge of the effects of artemisinins in relation to respiratory diseases to identify gaps that need to be filled in the course of repurposing artemisinins for the treatment of respiratory diseases. In addition, we postulate whether artemisinins can also be repurposed for the treatment of COVID-19 given its anti-viral and anti-inflammatory properties.