Coronavirus disease 2019 (COVID-19) is the second pandemic of the twenty-first century, with over one-hundred million infections and over two million deaths to date. It is a novel strain from the Coronaviridae family, named Severe Acute Respiratory Distress Syndrome Coronavirus-2 (SARS-CoV-2); the 7th known member of the coronavirus family to cause disease in humans, notably following the Middle East Respiratory syndrome (MERS), and Severe Acute Respiratory Distress Syndrome (SARS). The most characteristic feature of this single-stranded RNA molecule includes the spike glycoprotein on its surface. Most patients with COVID-19, of which the elderly and immunocompromised are most at risk, complain of flu-like symptoms, including dry cough and headache. The most common complications include pneumonia, acute respiratory distress syndrome, septic shock, and cardiovascular manifestations. Transmission of SARS-CoV-2 is mainly via respiratory droplets, either directly from the air when an infected patient coughs or sneezes, or in the form of fomites on surfaces. Maintaining hand-hygiene, social distancing, and personal protective equipment (i.e., masks) remain the most effective precautions. Patient management includes supportive care and anticoagulative measures, with a focus on maintaining respiratory function. Therapy with dexamethasone, remdesivir, and tocilizumab appear to be most promising to date, with hydroxychloroquine, lopinavir, ritonavir, and interferons falling out of favour. Additionally, accelerated vaccination efforts have taken place internationally, with several promising vaccinations being mass deployed. In response to the COVID-19 pandemic, countries and stakeholders have taken varying precautions to combat and contain the spread of the virus and dampen its collateral economic damage. This review paper aims to synthesize the impact of the virus on a global, micro to macro scale.

/pdf/covid-19-breaking-down-a-global-health-crisis-2hhce4628h.pdf

COVID-19: breaking down a global health crisis.

While coronavirus disease 2019 (COVID-19) is predominantly self-limited, up to 20% of symptomatic individuals will progress to severe or critical disease with clinical manifestations including pneumonia, acute respiratory distress syndrome, multiorgan system dysfunction, hypercoagulation, and hyperinflammatory manifestations. There have been more than 47 million cases of COVID-19 globally resulting in more than 1.2 million deaths. Additionally, a growing body of data suggests that some patients with COVID-19, including individuals with mild symptoms, will have a variably prolonged course of recovery including fatigue, cognitive impairment, and cardiopulmonary dysfunction.1 While treatment options for patients with severe disease requiring hospitalization are now available, with corticosteroids emerging as the treatment of choice for critically ill patients, interventions that can be administered early during the course of infection to prevent disease progression and longer-term complications are urgently needed.2,3 Recent attention has been focused on the potential of early treatment for individuals with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection at high risk for serious outcomes. Yet, there is a noteworthy absence of treatments proven to be

/pdf/therapy-for-early-covid-19-a-critical-need-3q46v3qtpq.pdf

Therapy for Early COVID-19: A Critical Need.

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a rapidly emerging virus causing the ongoing coronavirus disease 2019 (COVID-19) pandemic with no known effective prophylaxis. We investigated whether hydroxychloroquine could prevent SARS-CoV-2 in healthcare workers at high risk of exposure. Methods We conducted a randomized, double-blind, placebo-controlled clinical trial of healthcare workers with ongoing exposure to persons with SARS-CoV-2, including those working in emergency departments, intensive care units, COVID-19 hospital wards, and first responders. Participants across the United States and in the Canadian province of Manitoba were randomized to hydroxychloroquine loading dose then 400 mg once or twice weekly for 12 weeks. The primary endpoint was confirmed or probable COVID-19-compatible illness. We measured hydroxychloroquine whole-blood concentrations. Results We enrolled 1483 healthcare workers, of whom 79% reported performing aerosol-generating procedures. The incidence of COVID-19 (laboratory-confirmed or symptomatic compatible illness) was 0.27 events/person-year with once-weekly and 0.28 events/person-year with twice-weekly hydroxychloroquine compared with 0.38 events/person-year with placebo. For once-weekly hydroxychloroquine prophylaxis, the hazard ratio was .72 (95% CI, .44-1.16; P = .18) and for twice-weekly was .74 (95% CI, .46-1.19; P = .22) compared with placebo. Median hydroxychloroquine concentrations in whole blood were 98 ng/mL (IQR, 82-120) with once-weekly and 200 ng/mL (IQR, 159-258) with twice-weekly dosing. Hydroxychloroquine concentrations did not differ between participants who developed COVID-19-compatible illness (154 ng/mL) versus participants without COVID-19 (133 ng/mL; P = .08). Conclusions Pre-exposure prophylaxis with hydroxychloroquine once or twice weekly did not significantly reduce laboratory-confirmed COVID-19 or COVID-19-compatible illness among healthcare workers. Clinical trials registration Clinicaltrials.gov NCT04328467.

Hydroxychloroquine as Pre-exposure Prophylaxis for Coronavirus Disease 2019 (COVID-19) in Healthcare Workers: A Randomized Trial

BACKGROUND: Effective prevention against coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently limited to nonpharmaceutical strategies. Laboratory and observational data suggested that hydroxychloroquine had biological activity against SARS-CoV-2, potentially permitting its use for prevention. OBJECTIVE: To test hydroxychloroquine as postexposure prophylaxis for SARS-CoV-2 infection. DESIGN: Household-randomized, double-blind, controlled trial of hydroxychloroquine postexposure prophylaxis. (ClinicalTrials.gov: NCT04328961). SETTING: National U.S. multicenter study. PARTICIPANTS: Close contacts recently exposed ( 0.20). The frequency of participants experiencing adverse events was higher in the hydroxychloroquine group than the control group (66 [16.2%] versus 46 [10.9%], respectively; P = 0.026). LIMITATION: The delay between exposure, and then baseline testing and the first dose of hydroxychloroquine or ascorbic acid, was a median of 2 days. CONCLUSION: This rigorous randomized controlled trial among persons with recent exposure excluded a clinically meaningful effect of hydroxychloroquine as postexposure prophylaxis to prevent SARS-CoV-2 infection. PRIMARY FUNDING SOURCE: Bill & Melinda Gates Foundation.

/pdf/hydroxychloroquine-as-postexposure-prophylaxis-to-prevent-3tkjr8u1x1.pdf

Hydroxychloroquine as Postexposure Prophylaxis to Prevent Severe Acute Respiratory Syndrome Coronavirus 2 Infection : A Randomized Trial.

Coronavirus disease 2019 (COVID‐19), caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), continues to spread globally despite the worldwide implementation of preventive measures to combat the disease. Although most COVID‐19 cases are characterised by a mild, self‐limiting disease course, a considerable subset of patients develop a more severe condition, varying from pneumonia and acute respiratory distress syndrome (ARDS) to multi‐organ failure (MOF). Progression of COVID‐19 is thought to occur as a result of a complex interplay between multiple pathophysiological mechanisms, all of which may orchestrate SARS‐CoV‐2 infection and contribute to organ‐specific tissue damage. In this respect, dissecting currently available knowledge of COVID‐19 immunopathogenesis is crucially important, not only to improve our understanding of its pathophysiology, but also to fuel the rationale of both novel and repurposed treatment modalities. Various immune‐mediated pathways during SARS‐CoV‐2 infection are relevant in this context, which relate to innate immunity, adaptive immunity, and autoimmunity. Pathological findings in tissue specimens of patients with COVID‐19 provide valuable information with regard to our understanding of pathophysiology as well as the development of evidence‐based treatment regimens. This review provides an updated overview of the main pathological changes observed in COVID‐19 within the most commonly affected organ systems, with special emphasis on immunopathology. Current management strategies for COVID‐19 include supportive care and the use of repurposed or symptomatic drugs, such as dexamethasone, remdesivir, and anticoagulants. Ultimately, prevention is key to combat COVID‐19 and this requires appropriate measures to attenuate its spread and, above all, the development and implementation of effective vaccines.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/path.5642

COVID-19: immunopathology, pathophysiological mechanisms, and treatment options.

Importance Health care workers (HCWs) caring for patients with coronavirus disease 2019 (COVID-19) are at risk of exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, to our knowledge, there is no effective pharmacologic prophylaxis for individuals at risk. Objective To evaluate the efficacy of hydroxychloroquine to prevent transmission of SARS-CoV-2 in hospital-based HCWs with exposure to patients with COVID-19 using a pre-exposure prophylaxis strategy. Design, Setting, and Participants This randomized, double-blind, placebo-controlled clinical trial (the Prevention and Treatment of COVID-19 With Hydroxychloroquine Study) was conducted at 2 tertiary urban hospitals, with enrollment from April 9, 2020, to July 14, 2020; follow-up ended August 4, 2020. The trial randomized 132 full-time, hospital-based HCWs (physicians, nurses, certified nursing assistants, emergency technicians, and respiratory therapists), of whom 125 were initially asymptomatic and had negative results for SARS-CoV-2 by nasopharyngeal swab. The trial was terminated early for futility before reaching a planned enrollment of 200 participants. Interventions Hydroxychloroquine, 600 mg, daily, or size-matched placebo taken orally for 8 weeks. Main Outcomes and Measures The primary outcome was the incidence of SARS-CoV-2 infection as determined by a nasopharyngeal swab during the 8 weeks of treatment. Secondary outcomes included adverse effects, treatment discontinuation, presence of SARS-CoV-2 antibodies, frequency of QTc prolongation, and clinical outcomes for SARS-CoV-2–positive participants. Results Of the 132 randomized participants (median age, 33 years [range, 20-66 years]; 91 women [69%]), 125 (94.7%) were evaluable for the primary outcome. There was no significant difference in infection rates in participants randomized to receive hydroxychloroquine compared with placebo (4 of 64 [6.3%] vs 4 of 61 [6.6%];P > .99). Mild adverse events were more common in participants taking hydroxychloroquine compared with placebo (45% vs 26%;P = .04); rates of treatment discontinuation were similar in both arms (19% vs 16%;P = .81). The median change in QTc (baseline to 4-week evaluation) did not differ between arms (hydroxychloroquine: 4 milliseconds; 95% CI, −9 to 17; vs placebo: 3 milliseconds; 95% CI, −5 to 11;P = .98). Of the 8 participants with positive results for SARS-CoV-2 (6.4%), 6 developed viral symptoms; none required hospitalization, and all clinically recovered. Conclusions and Relevance In this randomized clinical trial, although limited by early termination, there was no clinical benefit of hydroxychloroquine administered daily for 8 weeks as pre-exposure prophylaxis in hospital-based HCWs exposed to patients with COVID-19. Trial Registration ClinicalTrials.gov Identifier:NCT04329923

/pdf/efficacy-and-safety-of-hydroxychloroquine-vs-placebo-for-pre-5bem4t957h.pdf

Barbara T. Biney

Papers

Efficacy and Safety of Hydroxychloroquine vs Placebo for Pre-exposure SARS-CoV-2 Prophylaxis Among Health Care Workers: A Randomized Clinical Trial.