COVID-19, SARS and MERS: A neurological perspective

Neurological Manifestations of Acute SARS-CoV-2 Infection in Pediatric Patients: A 3-Year Study on Differences between Pandemic Waves

This study analyzed the neurological manifestation profiles of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection across pandemic waves in pediatric patients. The study collected data on patients aged between 0 and 18 years, diagnosed with acute SARS-CoV-2 infection, admitted to a pediatric tertiary hospital between 1 March 2020 and 28 February 2023. This study included 1677 patients. Neurological manifestations were noted in 10% (n = 168) of patients with a median age of 3.2 years (interquartile range: 1-11.92). Neurological manifestations were significantly associated with the pandemic waves (p = 0.006) and age groups (p < 0.001). Seizures were noted in 4.2% of cases and reached an increasing frequency over time (p = 0.001), but were not associated with age groups. Febrile seizures accounted for the majority of seizures. Headache was reported in 2.6% of cases and had similar frequencies across the pandemic waves and age groups. Muscular involvement was noted in 2% of cases, reached a decreasing frequency over time (p < 0.001), and showed different frequencies among the age groups. Neurological manifestations of acute SARS-CoV-2 infection exhibit distinct patterns, depending on the pandemic wave and patient age group. The Wuhan and Omicron waves involved the nervous system more often than the other waves.

Long COVID: From olfactory dysfunctions to viral Parkinsonism

Neurological and psychiatric complications continue to be a public health concern in long coronavirus disease 2019 (COVID-19). This varies from olfactory dysfunctions such as parosmia to cognitive and emotional challenges. Historically, the surge of neurological disorders followed the viral pandemics, for example, the emergence of Encephalitis Lethargica after the outbreak of Spanish Influenza. During and after COVID-19 infection, the problems associated with the sense of smell and the reports of affected olfactory and limbic brain areas are leading to a growing concern about the similarity with the symptoms and the pattern of degeneration observed at the onset of Parkinson's disease and Alzheimer's disease. These reports reveal the essentiality of long-term studies of olfactory and cognitive functions in the post-COVID era and the experiments using animal models to dissect the neural basis of these complications. In this manuscript, we summarize the research reporting the potential correlation between neurological disorders and viral pandemic outbreaks with a historical perspective. Further, we discuss the studies providing evidence of neurodegeneration due to severe acute respiratory syndrome coronavirus 2 infection by focusing on viral Parkinsonism.

Blood-brain barrier disruption and sustained systemic inflammation in individuals with long COVID-associated cognitive impairment

Vascular disruption has been implicated in coronavirus disease 2019 (COVID-19) pathogenesis and may predispose to the neurological sequelae associated with long COVID, yet it is unclear how blood-brain barrier (BBB) function is affected in these conditions. Here we show that BBB disruption is evident during acute infection and in patients with long COVID with cognitive impairment, commonly referred to as brain fog. Using dynamic contrast-enhanced magnetic resonance imaging, we show BBB disruption in patients with long COVID-associated brain fog. Transcriptomic analysis of peripheral blood mononuclear cells revealed dysregulation of the coagulation system and a dampened adaptive immune response in individuals with brain fog. Accordingly, peripheral blood mononuclear cells showed increased adhesion to human brain endothelial cells in vitro, while exposure of brain endothelial cells to serum from patients with long COVID induced expression of inflammatory markers. Together, our data suggest that sustained systemic inflammation and persistent localized BBB dysfunction is a key feature of long COVID-associated brain fog.

SARS-CoV and SARS-CoV-2 display limited neuronal infection and lack the ability to transmit within synaptically connected axons in stem cell-derived human neurons

Sarbecoviruses such as SARS and SARS-CoV-2 have been responsible for two major outbreaks in humans, the latter resulting in a global pandemic. While sarbecoviruses primarily cause an acute respiratory infection, they have been shown to infect the nervous system. However, mechanisms of sarbecovirus neuroinvasion and neuropathogenesis remain unclear. In this study, we examined the infectivity and trans-synaptic transmission potential of the sarbecoviruses SARS and SARS-CoV-2 in human stem cell-derived neural model systems. We demonstrated limited ability of sarbecoviruses to infect and replicate in human stem cell-derived neurons. Furthermore, we demonstrated an inability of sarbecoviruses to transmit between synaptically connected human stem cell-derived neurons. Finally, we determined an absence of SARS-CoV-2 infection in olfactory neurons in experimentally infected ferrets. Collectively, this study indicates that sarbecoviruses exhibit low potential to infect human stem cell-derived neurons, lack an ability to infect ferret olfactory neurons, and lack an inbuilt molecular mechanism to utilise retrograde axonal trafficking and trans-synaptic transmission to spread within the human nervous system.

SARS-CoV-2 and Brain Health: New Challenges in the Era of the Pandemic

Respiratory viral infections have been found to have a negative impact on neurological functions, potentially leading to significant neurological impairment. The SARS-CoV-2 virus has precipitated a worldwide pandemic, posing a substantial threat to human lives. Growing evidence suggests that SARS-CoV-2 may severely affect the CNS and respiratory system. The current prevalence of clinical neurological issues associated with SARS-CoV-2 has raised significant concerns. However, there needs to be a more comprehensive understanding of the specific pathways by which SARS-CoV-2 enters the nervous system. Based on the available evidence, this review focuses on the clinical neurological manifestations of SARS-CoV-2 and the possible mechanisms by which SARS-CoV-2 invades the brain.

Pathophysiology, diagnosis, and management of neuroinflammation in covid-19

Although neurological complications of SARS-CoV-2 infection are relatively rare, their potential long term morbidity and mortality have a significant impact, given the large numbers of infected patients. Covid-19 is now in the differential diagnosis of a number of common neurological syndromes including encephalopathy, encephalitis, acute demyelinating encephalomyelitis, stroke, and Guillain-Barré syndrome. Physicians should be aware of the pathophysiology underlying these presentations to diagnose and treat patients rapidly and appropriately. Although good evidence has been found for neurovirulence, the neuroinvasive and neurotropic potential of SARS-CoV-2 is limited. The pathophysiology of most complications is immune mediated and vascular, or both. A significant proportion of patients have developed long covid, which can include neuropsychiatric presentations. The mechanisms of long covid remain unclear. The longer term consequences of infection with covid-19 on the brain, particularly in terms of neurodegeneration, will only become apparent with time and long term follow-up.

Enteric nervous system as a target and source of SARS-CoV-2 and other viral infections

Coronavirus disease 2019 (COVID-19) has been demonstrated to affect several systems of the human body, including the gastrointestinal and nervous systems. The enteric nervous system (ENS) is a division of the autonomic nervous system that extends throughout the gut, regulates gastrointestinal function, and is therefore involved in most gut dysfunctions, including those resulting from many viral infections. Growing evidence highlights enteric neural cells and microbiota as important players in gut inflammation and dysfunction. Furthermore, the ENS and gastrointestinal immune system work together establishing relevant neuroimmune interactions during both health and disease. In recent years, gut-driven processes have also been implicated as players in systemic inflammation and in the initiation and propagation of several central nervous system pathologies, which seem to be hallmarks of COVID-19. In this review, we aim to describe evidence of the gastrointestinal and ENS infection with a focus on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We discuss here viral-induced mechanisms, neuroplasticity, and neuroinflammation to call attention to the enteric neuroglial network as a nervous system with a sensitive and crucial position to be not only a target of the new coronavirus but also a way in and trigger of COVID-19-related symptoms.

Neutralization of SARS-CoV-2 (lineage B.1.1) by hyperimmune llama (Lama glama) serum in vero cell culture

OBJECTIVE.

To evaluate the serological antibody response of a llama (Lama glama) to SARS-CoV-2 (B.1.1 lineage) immunization and the neutralizing capacity of hyperimmune llama serum against SARS-CoV-2 virus (B.1.1 lineage) in Vero cells.

MATERIALS AND METHODS.

A llama was immunized with inactivated SARS-CoV-2 (B.1.1 lineage). Serum samples were analyzed to evaluate the level of antibodies by ELISA, as well as reactivity to SARS-CoV-2 antigens by Western Blot. In addition, viral neutralization in cell cultures was assessed by the Plate Reduction Neutralization Test (PRNT).

RESULTS

. Seroreactivity increased in the immunized llama from week 4 onwards. Antibody titers were the highest after the seventh immunization booster. Western blot results confirmed the positive ELISA findings, and immune serum antibodies recognized several viral proteins. The neutralization assay (PRNT) showed visible viral neutralization, which was in accordance with the ELISA and Western Blot results.

CONCLUSIONS.

The findings suggest that hyperimmune llama serum could constitute a source of therapeutic antibodies against SARS-CoV-2 infections (lineage B.1.1), and should be studied in further research.

Long COVID: Clinical characteristics, proposed pathogenesis and potential therapeutic targets

The emergence of persistent ill-health in the aftermath of SARS-CoV-2 infection has presented significant challenges to patients, healthcare workers and researchers. Termed long COVID, or post-acute sequelae of COVID-19 (PASC), the symptoms of this condition are highly variable and span multiple body systems. The underlying pathophysiology remains poorly understood, with no therapeutic agents proven to be effective. This narrative review describes predominant clinical features and phenotypes of long COVID alongside the data supporting potential pathogenesis of these phenotypes including ongoing immune dysregulation, viral persistence, endotheliopathy, gastrointestinal microbiome disturbance, autoimmunity, and dysautonomia. Finally, we describe current potential therapies under investigation, as well as future potential therapeutic options based on the proposed pathogenesis research.

Expert-opinion-based guidance for the care of children with lysosomal storage diseases during the COVID-19 pandemic: An experience-based Turkey perspective

This expert-opinion-based document was prepared by a group of specialists in pediatric inherited metabolic diseases and infectious diseases including administrative board members of Turkish Society for Pediatric Nutrition and Metabolism to provide guidance for the care of children with lysosomal storage disorders (LSDs) during the COVID-19 pandemic in Turkey. The experts reached consensus on key areas of focus regarding COVID-19-based risk status in relation to intersecting immune-inflammatory mechanisms and disease patterns in children with LSDs, diagnostic virus testing, particularly preventive measures and priorities during the pandemic, routine screening and diagnostic interventions for LSDs, psychological and socioeconomic impact of confinement measures and quarantines and optimal practice patterns in managing LSDs and/or COVID-19. The participating experts agreed on the intersecting characteristics of immune-inflammatory mechanisms, end-organ damage and prognostic biomarkers in LSD and COVID-19 populations, emphasizing the likelihood of enhanced clinical care when their interaction is clarified via further studies addressing certain aspects related to immunity, lysosomal dysfunction and disease pathogenesis. In the context of the current global COVID-19 pandemic, this expert-opinion-based document provides guidance for the care of children with LSDs during the COVID-19 pandemic based on the recent experience in Turkey.

Identifying cerebral microstructural changes in patients with COVID-19 using MRI: A systematic review

Coronavirus disease 2019 (COVID-19) is an epidemic viral disease caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite the excessive number of neurological articles that have investigated the effect of COVID-19 on the brain from the neurological point of view, very few studies have investigated the impact of COVID-19 on the cerebral microstructure and function of the brain. The aim of this study was to summarize the results of the existing studies on cerebral microstructural changes in COVID-19 patients, specifically the use of quantitative volumetric analysis, blood oxygen level dependent (BOLD), and diffusion tensor imaging (DTI). We searched PubMed/MEDLINE, ScienceDirect, Semantic Scholar, and Google Scholar from December 2020 to April 2022. A well-constructed search strategy was used to identify the articles for review. Seven research articles have met this study's inclusion and exclusion criteria, which have applied neuroimaging tools such as quantitative volumetric analysis, BOLD, and DTI to investigate cerebral microstructure changes in COVID-19 patients. A significant effect of COVID-19 was found in the brain such as hypoperfusion of cerebral blood flow, increased gray matter (GM) volume, and reduced cortical thickness. The insula and thalamic radiation were the most frequent GM region and white matter tract, respectively, that are involved in SARS-CoV-2. COVID-19 was found to be associated with changes in cerebral microstructures. These abnormalities in brain areas might lead to be associated with behaviors, mental and neurological alterations that need to be considered carefully in future studies.

Neurologic Presentations of COVID-19: A Case Series

Introduction: The new pandemic of coronavirus disease 2019 (COVID-19) has evolved certain neurologic syndromes as a presentation of this disease that should be integrated into the whole disease process. Case Presentations: We present cases of neurologic involvement in adult patients with documented bronchopulmonary COVID-19. Certain signs and symptoms are introduced, including new onset seizures, ischemic stroke, and altered mental status in otherwise minimal clinical signs and symptoms of COVID-19. Conclusions: Many neurologic presentations are diagnosed in resolving COVID respiratory infections or in an otherwise asymptomatic individual.

Role of aging in Blood-Brain Barrier dysfunction and susceptibility to SARS-CoV-2 infection: impacts on neurological symptoms of COVID-19

COVID-19, which is caused by Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2), has resulted in devastating morbidity and mortality worldwide due to lethal pneumonia and respiratory distress. In addition, the central nervous system (CNS) is well documented to be a target of SARS-CoV-2, and studies detected SARS-CoV-2 in the brain and the cerebrospinal fluid of COVID-19 patients. The blood-brain barrier (BBB) was suggested to be the major route of SARS-CoV-2 infection of the brain. Functionally, the BBB is created by an interactome between endothelial cells, pericytes, astrocytes, microglia, and neurons, which form the neurovascular units (NVU). However, at present, the interactions of SARS-CoV-2 with the NVU and the outcomes of this process are largely unknown. Moreover, age was described as one of the most prominent risk factors for hospitalization and deaths, along with other comorbidities such as diabetes and co-infections. This review will discuss the impact of SARS-CoV-2 on the NVU, the expression profile of SARS-CoV-2 receptors in the different cell types of the CNS and the possible role of aging in the neurological outcomes of COVID-19. A special emphasis will be placed on mitochondrial functions because dysfunctional mitochondria are also a strong inducer of inflammatory reactions and the "cytokine storm" associated with SARS-CoV-2 infection. Finally, we will discuss possible drug therapies to treat neural endothelial function in aged patients, and, thus, alleviate the neurological symptoms associated with COVID-19.

An overview of the neurological aspects in COVID-19 infection

The Crown-shaped, severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) triggered the globally fatal illness of Coronavirus disease-2019 (COVID-19). This infection is known to be initially reported in bats and has been causing major respiratory challenges. The primary symptoms of COVID-19 include fever, fatigue and dry cough. As progressed the complications may lead to acute respiratory distress syndrome (ADRS), arrhythmia and shock. This review illustrates the neurological and neuropsychiatric impairments due to COVID-19 infection. The SARS-CoV-2 virus enters via the hematogenous or neural route, spreads to the Central Nervous System (CNS), causing a blood-brain barrier (BBB) dysfunction. Recent scientific articles have reported that SARS-CoV-2 causes several neurological issues such as encephalitis, seizures, acute stroke, delirium, meningoencephalitis and Guillain-Barré Syndrome (GBS). As a long-term effect of this disease certain neuropsychiatric conditions are witnessed such as depression and anxiety. Invasion into followed by degeneration takes place causing an uncontrolled immune response. Transcription factors like NF-κB (nuclear factor kappa light chain enhancer of activated B cells), which modulate genes responsible for inflammatory response gets over expressed. Nrf2 (nuclear factor erythroid 2- related factor 2) counterpoises the inflammation by antioxidant response towards COVID-19 infection. Like every other infection, the severity of this infection leads to deterioration of major organ systems and even leads to death. By the columns of this review, we elaborate on the neurological aspects of this life-threatening infection.

Systematic Review of the Common Pathophysiological Mechanisms in COVID-19 and Neurodegeneration: The Role of Bioactive Compounds and Natural Antioxidants

The novel coronavirus (2019-nCoVCOVID-19) belongs to the Beta coronavirus family, which contains MERS-CoV (Middle East respiratory syndrome coronavirus) and SARS-CoV (severe acute respiratory syndrome coronavirus). SARS-CoV-2 activates the innate immune system, thereby activating the inflammatory mechanism, causing the release of inflammatory cytokines. Moreover, it has been suggested that COVID-19 may penetrate the central nervous system, and release inflammatory cytokines in the brains, inducing neuroinflammation and neurodegeneration. Several links connect COVID-19 with Alzheimer’s disease (AD), such as elevated oxidative stress, uncontrolled release of the inflammatory cytokines, and mitochondrial apoptosis. There are severe concerns that excessive immune cell activation in COVID-19 may aggravate the neurodegeneration and amyloid-beta pathology of AD. Here, we have collected the evidence, showing the links between the two diseases. The focus has been made to collect the information on the activation of the inflammation, its contributors, and shared therapeutic targets. Furthermore, we have given future perspectives, research gaps, and overlapping pathological bases of the two diseases. Lastly, we have given the short touch to the drugs that have equally shown rescuing effects against both diseases. Although there is limited information available regarding the exact links between COVID-19 and neuroinflammation, we have insight into the pathological contributors of the diseases. Based on the shared pathological features and therapeutic targets, we hypothesize that the activation of the immune system may induce neurological disorders by triggering oxidative stress and neuroinflammation.

COVID-19, Oxidative Stress, and Neuroinflammation in the Depression Route

COVID-19 is associated with oxidative stress, peripheral hyper inflammation, and neuroinflammation, especially in individuals with a more severe form of the disease. Some studies provide evidence on the onset or exacerbation of major depressive disorder (MDD), among other psychiatric disorders due to COVID-19. Oxidative stress and neuroinflammation are associated conditions, especially in the more severe form of MDD and in refractoriness to available therapeutic strategies. Inflammatory cytokines in the COVID-19 hyper inflammation process can activate the hypothalamic–pituitary–adrenal (HPA) axis and the indoleamine-2,3-dioxygenase (IDO) enzyme. IDO activation can reduce tryptophan and increase toxic metabolites of the kynurenine pathway, which increases glial activation, neuroinflammation, toxicity, and neuronal death. This review surveyed a number of studies and analyzed the mechanisms of oxidative stress, inflammation, and neuroinflammation involved in COVID-19 and depression. Finally, the importance of more protocols that can help elucidate the interaction between these mechanisms underlying COVID-19 and MDD and the possible therapeutic strategies involved in the interaction of these mechanisms are highlighted.

SARS-COV-2 - the pandemic of the XXI century, clinical manifestations - neurological implications

In December 2019, in Wuhan, China, the first cases of infection with SARS-CoV 2 responsible for COVID-19 disease were identified. SARS-CoV 2 was declared a pandemic on March 11, 2020, and since then has attracted the medical world's attention. The threat to humans' health that this emerging pandemic could leave raises awareness on the importance of understanding the mechanisms that underlie the developing conditions. The epidemiology, clinical picture, and pathogenesis of COVID-19 show that this virus presents new strategies to overcome the past defensive medicine. While all the current data has focused on the pulmonary and cardiovascular manifestations, little has been written about the neurological implications of the disease. This review updates new clinical aspects that SARS-CoV 2 expresses in humans by focusing primarily on neurological manifestations. The damage to the nervous system became more apparent - anosmia, ageusia, polyneuritis, meningitis, meningoencephalitis, stroke, acute necrotizing encephalopathy. Oxygen therapy is vital for those in critical health situations. Finally, prevention is the most important element in breaking the epidemiological chain.

Neurologic manifestations in children with COVID-19 from a tertiary center in Turkey and literature review

BACKGROUND

Since December 2019, coronavirus disease 2019 (COVID-19) has become a global pandemic caused by highly transmissible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although respiratory disease and multisystem inflammatory syndrome in children (MIS-C) are main clinical presentations in children, numerous neurological manifestations are being described increasingly. We aimed to investigate new onset neurological symptoms associated with SARS-CoV-2 in pediatric patients in order to establish a possible relationship as well as to understand the underlying pathophysiological mechanisms between SARS-CoV-2 infection and neurological findings.

METHODS

We analyzed retrospectively children who had neurologic manifestations temporally associated with SARS-CoV-2 infection at Hacettepe University İhsan Doğramaci Children's Hospital. We performed a literature search between March 20, 2020 and March 30, 2021. Articles that report children with COVID-19 related neurological manifestations were included.

RESULTS

We have observed 15 consecutive cases with new onset neurological manifestations along with confirmed SARS-CoV-2 infection. Age at hospitalization ranged from three months to 17 years. Ten patients had central nervous system involvement, and most common manifestation was encephalopathy (5/10), which is also one of the most common manifestations of the patients mentioned in the relevant 39 articles we reviewed.

CONCLUSION

Children with COVID-19 can present with neurologic findings such as encephalopathy, seizures, cerebrovascular events as well as abnormal eye movements. Clinical suspicion and awareness are required to show the association between neurologic manifestations and COVID-19.

Intranasal dexamethasone: a new clinical trial for the control of inflammation and neuroinflammation in COVID-19 patients

Background

By end December of 2021, COVID-19 has infected around 276 million individuals and caused over 5 million deaths worldwide. Infection results in dysregulated systemic inflammation, multi-organ dysfunction, and critical illness. Cells of the central nervous system are also affected, triggering an uncontrolled neuroinflammatory response. Low doses of glucocorticoids, administered orally or intravenously, reduce mortality among moderate and severe COVID-19 patients. However, low doses administered by these routes do not reach therapeutic levels in the CNS. In contrast, intranasally administered dexamethasone can result in therapeutic doses in the CNS even at low doses.

Methods

This is an approved open-label, multicenter, randomized controlled trial to compare the effectiveness of intranasal versus intravenous dexamethasone administered in low doses to moderate and severe COVID-19 adult patients. The protocol is conducted in five health institutions in Mexico City. A total of 120 patients will be randomized into two groups (intravenous vs. intranasal) at a 1:1 ratio. Both groups will be treated with the corresponding dexamethasone scheme for 10 days. The primary outcome of the study will be clinical improvement, defined as a statistically significant reduction in the NEWS-2 score of patients with intranasal versus intravenous dexamethasone administration. The secondary outcome will be the reduction in mortality during hospitalization.

Conclusions

This protocol is currently in progress to improve the efficacy of the standard therapeutic dexamethasone regimen for moderate and severe COVID-19 patients.

Trial registration

ClinicalTrials.govNCT04513184. Registered November 12, 2020. Approved by La Comisión Federal para la Protección contra Riesgos Sanitarios (COFEPRIS) with identification number DI/20/407/04/36. People are currently being recruited.

Graphical abstract

REVIVAL is a multicenter, open-label, randomized, controlled study to compare the standard low doses of intravenous dexamethasone with weight-adjusted low doses of intranasal dexamethasone.

Intranasal dexamethasone can reach the respiratory tract more effectively than intravenous administration.

Intranasal dexamethasone can reach the central nervous system in therapeutic concentrations, even at low doses.

REVIVAL aims to reduce central failures and sequelae by controlling not only systemic inflammation but also neuroinflammation.

Neurological Associations of SARS-CoV-2 Infection: A Systematic Review

BACKGROUND

The current ongoing COVID-19 pandemic has compelled us to scrutinize major outbreaks in the past two decades, Severe Acute Respiratory Syndrome (SARS), in 2002, and Middle East Respiratory Syndrome (MERS), in 2012. We aimed to assess the associated neurological manifestations with SARS CoV-2 infection.

METHODS

In this systematic review, a search was carried out by key-electronic databases, controlled vocabulary, and indexing of trials to evaluate the available pertinent studies which included both medical subject headings (MeSH) and advanced electronic databases comprising PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL). Peer-reviewed studies published in English and Spanish were considered, which reported data on the neurological associations of individuals with suspected or laboratory-confirmed SARS-CoV-2 infection. Outcomes were nervous signs or symptoms, symptom severity, and diagnoses.

RESULTS

Our search identified 45 relevant studies, with 21 case reports, 3 case series, 9 observational studies, 1 retrospective study, 9 retrospective reviews, and 2 prospective reviews. This systematic review revealed that most commonly reported neuronal presentations involved headache, nausea, vomiting and muscular symptoms like fibromyalgia. Anosmia and ageusia, defects in clarity or sharpness of vision (error in visual acuity), and pain may occur in parallel. Notable afflictions in the form of anxiety, anger, confusion, post-traumatic stress symptoms, and post-intensive care syndrome were observed in individuals who were kept in quarantine and those with long-stay admissions in healthcare settings. SARS CoV-2 infection may result in cognitive impairment. Patients with more severe infection exhibited uncommon manifestations, such as acute cerebrovascular diseases (intracerebral haemorrhage, stroke), rhabdomyolysis, encephalopathy, and Guillain-Barré syndrome.

CONCLUSION

SARS-CoV-2 patients experience neuronal presentations varying with the progression of the infection. Healthcare professionals should be acquainted with the divergent neurological symptoms to curb misdiagnosis and limit long-term sequelae. Health-care planners and policymakers must prepare for this eventuality, while the ongoing studies increase our knowledge base on acute and chronic neurological associations of this pathogen.

Alzheimer's-like signaling in brains of COVID-19 patients

Introduction

The mechanisms that lead to cognitive impairment associated with COVID‐19 are not well understood.

Methods

Brain lysates from control and COVID‐19 patients were analyzed for oxidative stress and inflammatory signaling pathway markers, and measurements of Alzheimer’s disease (AD)‐linked signaling biochemistry. Post‐translational modifications of the ryanodine receptor/calcium (Ca2⁺) release channels (RyR) on the endoplasmic reticuli (ER), known to be linked to AD, were also measured by co‐immunoprecipitation/immunoblotting of the brain lysates.

Results

We provide evidence linking SARS‐CoV‐2 infection to activation of TGF‐β signaling and oxidative overload. The neuropathological pathways causing tau hyperphosphorylation typically associated with AD were also shown to be activated in COVID‐19 patients. RyR2 in COVID‐19 brains demonstrated a “leaky” phenotype, which can promote cognitive and behavioral defects.

Discussion

COVID‐19 neuropathology includes AD‐like features and leaky RyR2 channels could be a therapeutic target for amelioration of some cognitive defects associated with SARS‐CoV‐2 infection and long COVID.

Characteristics of COVID and post COVID polyneuropathies in adults and pediatrics: an Egyptian sample

Background

The aim of this study is to describe the different forms of polyneuropathy associated with coronavirus disease 2019 (COVID-19) as a secondary neurological complication for (COVID-19) and the outcome from different therapeutic regimens in adults and pediatrics in first and second waves of the pandemic.

Case presentation

This study was conducted on 42 patients, they were divided into two groups, group (A) and group (B) in first and second waves respectively. Twenty-five patients presented by ascending weakness preceded by fever, dry cough and respiratory distress, electromyography (EMG) and nerve conduction (NC) studies done and confirmed the clinical diagnosis of demyelinating polyneuropathy. Eight patients presented by acute flaccid quadriparesis, more severe in upper limbs preceded by fever and diarrhea diagnosed as acute axonal polyneuropathy. Five patients presented by severe fatigue and progressive weakness of both lower and upper limbs, they developed fever and cough 10 days after the neurological symptoms. EMG and NC done and confirmed clinical diagnosis of polyneuropathy of demyelinating with secondary axonal picture. Four patients presented 30 to 40 days after their recovery form corona virus infection with gradual progressive weakness of both upper and lower limbs over 2 to 3 months duration, mainly the proximal muscles of lower limbs were affected with areflexia. EMG and NC done and confirmed the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP).

Conclusion

We should gain a better understanding of the underlying pathophysiology and therapeutic options of polyneuropathies related to COVID-19, which will have an impact on the treatment of the COVID related respiratory failure presenting with neuropathy.

Evaluating the Impact of COVID-19 on Society, Environment, Economy, and Education

The COVID-19 pandemic has caused drastic changes across the globe, affecting all areas of life. This paper provides a comprehensive study on the influence of COVID-19 in various fields such as the economy, education, society, the environment, and globalization. In this study, both the positive and negative consequences of the COVID-19 pandemic on education are studied. Modern technologies are combined with conventional teaching to improve the communication between instructors and learners. COVID-19 also greatly affected people with disabilities and those who are older, with these persons experiencing more complications in their normal routine activities. Additionally, COVID-19 provided negative impacts on world economies, greatly affecting the business, agriculture, entertainment, tourism, and service sectors. The impact of COVID-19 on these sectors is also investigated in this study, and this study provides some meaningful insights and suggestions for revitalizing the tourism sector. The association between globalization and travel restrictions is studied. In addition to economic and human health concerns, the influence of a lockdown on environmental health is also investigated. During periods of lockdown, the amount of pollutants in the air, soil, and water was significantly reduced. This study motivates researchers to investigate the positive and negative consequences of the COVID-19 pandemic in various unexplored areas.

Neurological manifestations of coronavirus infections, before and after COVID-19: a review of animal studies

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus, which was first identified in December 2019 in China, has resulted in a yet ongoing viral pandemic. Coronaviridae could potentially cause several disorders in a wide range of hosts such as birds and mammals. Although infections caused by this family of viruses are predominantly limited to the respiratory tract, Betacoronaviruses are potentially able to invade the central nervous system (CNS) as well as many other organs, thereby inducing neurological damage ranging from mild to lethal in both animals and humans. Over the past two decades, three novel CoVs, SARS-CoV-1, MERS-CoV, and SARS-CoV-2, emerging from animal reservoirs have exhibited neurotropic properties causing severe and even fatal neurological diseases. The pathobiology of these neuroinvasive viruses has yet to be fully known. Both clinical features of the previous CoV epidemics (SARS-CoV-1 and MERS-CoV) and lessons from animal models used in studying neurotropic CoVs, especially SARS and MERS, constitute beneficial tools in comprehending the exact mechanisms of virus implantation and in illustrating pathogenesis and virus dissemination pathways in the CNS. Here, we review the animal research which assessed CNS infections with previous more studied neurotropic CoVs to demonstrate how experimental studies with appliable animal models can provide scientists with a roadmap in the CNS impacts of SARS-CoV-2. Indeed, animal studies can finally help us discover the underlying mechanisms of damage to the nervous system in COVID-19 patients and find novel therapeutic agents in order to reduce mortality and morbidity associated with neurological complications of SARS-CoV-2 infection.

Worldwide epidemiology of neuro-coronavirus disease in children: lessons for the next pandemic

PURPOSE OF REVIEW

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic has overwhelmed the global community, negatively impacting patient health and research efforts; associated neurological manifestations are a significant cause of morbidity. This review outlines the worldwide epidemiology of neurologic manifestations of different SARS-CoV-2 clinical pediatric phenotypes, including acute coronavirus disease 2019 (COVID-19), multisystem inflammatory syndrome in children (MIS-C) and postacute sequelae of COVID-19 (PASC). We discuss strategies to develop adaptive global research platforms for future investigation into emerging pediatric neurologic conditions.

RECENT FINDINGS

Multicenter, multinational studies show that neurological manifestations of acute COVID-19, such as smell/taste disorders, headache, and stroke, are common in hospitalized adults (82%) and children (22%), associated with increased mortality in adults. Neurological manifestations of MIS-C are reported in up to 20% of children, including headache, irritability, and encephalopathy. Data on PASC are emerging and include fatigue, cognitive changes, and headache. Reports of neurological manifestations in each phenotype are limited by lack of pediatric-informed case definitions, common data elements, and resources.

SUMMARY

Coordinated, well resourced, multinational investigation into SARS-CoV-2-related neurological manifestations in children is critical to rapid identification of global and region-specific risk factors, and developing treatment and mitigation strategies for the current pandemic and future health neurologic emergencies.

Acute disseminated encephalomyelitis and myelitis associated with new coronavirus infection COVID-19. Case report

Acute disseminated encephalomyelitis (AEM) and acute transverse myelitis (OPM) are autoimmune demyelinating diseases of the central nervous system. Two clinical observations of AEM and OPM developed after suffering acute coronavirus infection (SARS-CoV-2) are presented. Differential diagnosis was carried out with multiple sclerosis, encephalitis of an infectious nature, compressive myelopathy, and opticomyelitis. Both observations show an almost complete recovery of lost functions. The pathogenetic mechanisms of the development of AEM and OPM in patients with coronavirus infection are discussed. The onset of central nervous system dysimmune lesion in the context of coronavirus infection makes it necessary to monitor the clinical situation with the involvement of a neurologist for timely diagnosis and determination of therapeutic tactics that can reduce the degree of disability of patients.

Aeromedical Implications of Long-Term COVID-19 Sequelae

BACKGROUND: While many COVID-19 studies focus on acute effects of the infection, few examine the intermediate and long-term sequelae of the illness. Studies have shown that a good portion of patients have chronic effects in several body systems for several months or longer. Such effects can potentially adversely impact pilot performance in flight. We sought to determine the long-term effects of COVID-19 infection, how such effects can affect pilot performance, and how to best evaluate pilots for aeromedical flight clearance.METHODS: We used the PubMed literature search engine to review peer-reviewed articles that focused on the intermediate and long-term effects of COVID-19 infection. Chronic signs and symptoms were subdivided based on the particular body organ system affected. Merging information obtained from case reviews, article reviews, and aeromedical standards, we created a risk stratification guide to assist with the aeromedical disposition of affected pilots.RESULTS: Long-term effects of COVID-19 infection can last for several months or longer. The most common effects are fatigue, weakness, pulmonary diffusion defects, depression, and anxiety.DISCUSSION: This review article focuses on the most common intermediate- and long-term COVID-19 conditions of aeromedical significance and the corresponding course of actions recommended for the aeromedical examiner. Aeromedical evaluation should take into consideration factors related to the pilot, aircraft type, and specific aviation environment. Such evaluation may include diagnostic testing, medical specialist consultation, preflight simulation in an altitude chamber, human centrifuge testing, and/or a flight simulator checkride.Ko SY, Nguyen NK, Lee CL, Lee LA, Nguyen KUT, Lee EC. Aeromedical implications of long-term COVID-19 sequelae. Aerosp Med Hum Perform. 2021; 92(11):898-907.

SARS-CoV-2 S1 Protein Induces Endolysosome Dysfunction and Neuritic Dystrophy

SARS-CoV-2 is the viral cause of the COVID-19 pandemic. Increasingly, significant neurological disorders have been associated with COVID-19. However, the pathogenesis of these neurological disorders remains unclear especially because only low or undetectable levels of SARS-CoV-2 have been reported in human brain specimens. Because SARS-CoV-2 S1 protein can be released from viral membranes, can cross the blood-brain barrier, and is present in brain cells including neurons, we tested the hypothesis that SARS-CoV-2 S1 protein can directly induce neuronal injury. Incubation of primary human cortical neurons with SARS-CoV-2 S1 protein resulted in accumulation of the S1 protein in endolysosomes as well as endolysosome de-acidification. Further, SARS-CoV-2 S1 protein induced aberrant endolysosome morphology and neuritic varicosities. Our findings suggest that SARS-CoV-2 S1 protein directly induces neuritic dystrophy, which could contribute to the high incidence of neurological disorders associated with COVID-19.

Covid-19 interface with drug misuse and substance use disorders

The coronavirus disease 2019 (Covid-19) pandemic intensified the already catastrophic drug overdose and substance use disorder (SUD) epidemic, signaling a syndemic as social isolation, economic and mental health distress, and disrupted treatment services disproportionally impacted this vulnerable population. Along with these social and societal factors, biological factors triggered by intense stress intertwined with incumbent overactivity of the immune system and the resulting inflammatory outcomes may impact the functional status of the central nervous system (CNS). We review the literature concerning SARS-CoV2 infiltration and infection in the CNS and the prospects of synergy between stress, inflammation, and kynurenine pathway function during illness and recovery from Covid-19. Taken together, inflammation and neuroimmune signaling, a consequence of Covid-19 infection, may dysregulate critical pathways and underlie maladaptive changes in the CNS, to exacerbate the development of neuropsychiatric symptoms and in the vulnerability to develop SUD. This article is part of the special Issue on 'Vulnerabilities to Substance Abuse'.

Early Neurorehabilitation and Recovery from Disorders of Consciousness After Severe COVID-19

Background

Early neurorehabilitation improves outcomes in patients with disorders of consciousness (DoC) after brain injury, but its applicability in COVID-19 is unknown. We describe our experience implementing an early neurorehabilitation protocol for patients with COVID-19-associated DoC in the intensive care unit (ICU) and evaluate factors associated with recovery.

Methods

During the initial COVID-19 surge in New York City between March 10 and May 20, 2020, faced with a disproportionately high number of ICU patients with prolonged unresponsiveness, we developed and implemented an early neurorehabilitation protocol, applying standard practices from brain injury rehabilitation care to the ICU setting. Twenty-one patients with delayed recovery of consciousness after severe COVID-19 participated in a pilot early neurorehabilitation program that included serial Coma Recovery Scale-Revised (CRS-R) assessments, multimodal treatment, and access to clinicians specializing in brain injury medicine. We retrospectively compared clinical features of patients who did and did not recover to the minimally conscious state (MCS) or better, defined as a CRS-R total score (TS) ≥ 8, before discharge. We additionally examined factors associated with best CRS-R TS, last CRS-R TS, hospital length of stay, and time on mechanical ventilation.

Results

Patients underwent CRS-R assessments a median of six (interquartile range [IQR] 3–10) times before discharge, beginning a median of 48 days (IQR 40–55) from admission. Twelve (57%) patients recovered to MCS after a median of 8 days (IQR 2–14) off continuous sedation; they had lower body mass index (p = 0.009), lower peak serum C-reactive protein levels (p = 0.023), higher minimum arterial partial pressure of oxygen (p = 0.028), and earlier fentanyl discontinuation (p = 0.018). CRS-R scores fluctuated over time, and the best CRS-R TS was significantly higher than the last CRS-R TS (median 8 [IQR 5–23] vs. 5 [IQR 3–18], p = 0.002). Earlier fentanyl (p = 0.001) and neuromuscular blockade (p = 0.015) discontinuation correlated with a higher last CRS-R TS.

Conclusions

More than half of our cohort of patients with prolonged unresponsiveness following severe COVID-19 recovered to MCS or better before hospital discharge, achieving a clinical benchmark known to have relatively favorable long-term prognostic implications in DoC of other etiologies. Hypoxia, systemic inflammation, sedation, and neuromuscular blockade may impact diagnostic assessment and prognosis, and fluctuations in level of consciousness make serial assessments essential. Early neurorehabilitation of these patients in the ICU can be accomplished but is associated with unique challenges. Further research should evaluate factors associated with longer-term neurologic recovery and benefits of early rehabilitation in patients with severe COVID-19.

Facial Nerve Palsy as a Neurological Manifestation of COVID-19

Facial nerve palsy is the most frequent acute mononeuropathy and it is often of viral etiology, although many other causes have been identified. It has recently been described as a potential manifestation of COVID-19. We report the case of a patient with recent history of diarrhea and malaise that was admitted to the hospital presenting right facial paresis with orbicular muscle involvement. Nasopharyngeal swab tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the real-time reverse transcription polymerase chain reaction and magnetic resonance imaging showed no structural changes. During the hospital stay, the patient showed clinical improvement, and no other symptoms were observed. This case presentation suggests a possible association between neuropathies and SARS-CoV-2 infection.

Neuropsychiatric Disorders and COVID-19: What We Know So Far

SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) affects the central nervous system (CNS), which is shown in a significant number of patients with neurological events. In this study, an updated literature review was carried out regarding neurological disorders in COVID-19. Neurological symptoms are more common in patients with severe infection according to their respiratory status and divided into three categories: (1) CNS manifestations; (2) cranial and peripheral nervous system manifestations; and (3) skeletal muscle injury manifestations. Patients with pre-existing cerebrovascular disease are at a higher risk of admission to the intensive care unit (ICU) and mortality. The neurological manifestations associated with COVID-19 are of great importance, but when life-threatening abnormal vital signs occur in severely ill COVID-19 patients, neurological problems are usually not considered. It is crucial to search for new treatments for brain damage, as well as for alternative therapies that recover the damaged brain and reduce the inflammatory response and its consequences for other organs. In addition, there is a need to diagnose these manifestations as early as possible to limit long-term consequences. Therefore, much research is needed to explain the involvement of SARS-CoV-2 causing these neurological symptoms because scientists know zero about it.

Hemorrhagic and thrombotic manifestations in the central nervous system in COVID-19: A large observational study in the Brazilian Amazon with a complete autopsy series

SARS-CoV-2 affects mainly the lungs, however, other manifestations, including neurological manifestations, have also been described during the disease. Some of the neurological findings have involved intracerebral or subarachnoid hemorrhage, strokes, and other thrombotic/hemorrhagic conditions. Nevertheless, the gross pathology of hemorrhagic lesions in the central nervous system has not been previously described in Brazilian autopsy cases. This study aimed to describe gross and microscopic central nervous system (CNS) pathology findings from the autopsies and correlate them with the clinical and laboratory characteristics of forty-five patients with COVID-19 from Manaus, Amazonas, Brazil. Forty-four patients were autopsied of which thirty-eight of these (86.36%) were positive by RT-PCR for COVID-19, and six (13.3%) were positive by the serological rapid test. Clinical and radiological findings were compatible with the infection. The patients were classified in two groups: presence (those who had hemorrhagic and/or thrombotic manifestations in the CNS) and absence (those who did not present hemorrhagic and/or thrombotic manifestations in the CNS). For risk assessment, relative risk and respective confidence intervals were estimated. Macroscopic or microscopic hemorrhages were found in twenty-three cases (52,27%). The postmortem gross examination of the brain revealed a broad spectrum of hemorrhages, from spots to large and confluent areas and, under microscopy, we observed mainly perivascular discharge. The association analyses showed that the use of corticosteroid, anticoagulant and antibiotic had no statistical significance with a risk of nervous system hemorrhagic manifestations. However, it is possible to infer a statistical tendency that indicates that individuals with diabetes had a higher risk for the same outcome (RR = 1.320, 95% CI = 0.7375 to 2.416, p = 0.3743), which was not observed in relation to other comorbidities. It is unknown whether the new variants of the virus can cause different clinical manifestations, such as those observed or indeed others. As a result, more studies are necessary to define clinical and radiologic monitoring protocols and strategic interventions for patients at risk of adverse and fatal events, such as the extensive hemorrhaging described here. It is imperative that clinicians must be aware of comorbidities and the drugs used to treat patients with COVID-19 to prevent CNS hemorrhagic and thrombotic events.

The effect of SARS-CoV-2 on the nervous system: a review of neurological impacts caused by human coronaviruses

The COVID-19 pandemic has affected millions of people worldwide. While coronaviruses typically have low rates of neurotropic effects, the massive transmission of SARS-CoV-2 suggests that a substantial population will suffer from potential SARS-CoV-2-related neurological disorders. The rapid and recent emergence of SARS-CoV-2 means little research exists on its potential neurological effects. Here we analyze the effects of similar viruses to provide insight into the potential effects of SARS-CoV-2 on the nervous system and beyond. Seven coronavirus strains (HCoV-OC43, HCoV-HKU1, HCoV-229E, HCoV-NL63, SARS-CoV, MERS-CoV, SARS-CoV-2) can infect humans. Many of these strains cause neurological effects, such as headaches, dizziness, strokes, seizures, and critical illness polyneuropathy/myopathy. Certain studies have also linked coronaviruses with multiple sclerosis and extensive central nervous system injuries. Reviewing these studies provides insight into the anticipated effects for patients with SARS-CoV-2. This review will first describe the effects of other coronaviruses that have caused severe disease (SARS-CoV, MERS-CoV) on the nervous system, as well as their proposed origins, non-neurological effects, and neurological infection mechanisms. It will then discuss what is known about SARS-CoV-2 in these areas with reference to the aforementioned viruses, with the goal of providing a holistic picture of SARS-CoV-2.

SARS-CoV-2 and the Brain: What Do We Know about the Causality of 'Cognitive COVID?

The second year of the COVID-19 (coronavirus disease) pandemic has seen the need to identify and assess the long-term consequences of a SARS-CoV-2 infection on an individual's overall wellbeing, including adequate cognitive functioning. 'Cognitive COVID' is an informal term coined to interchangeably refer to acute changes in cognition during COVID-19 and/or cognitive sequelae with various deficits following the infection. These may manifest as altered levels of consciousness, encephalopathy-like symptoms, delirium, and loss of various memory domains. Dysexecutive syndrome is a peculiar manifestation of 'Cognitive COVID' as well. In the previous major outbreaks of viruses like SARS-CoV, MERS-CoV and Influenza. There have been attempts to understand the underlying mechanisms describing the causality of similar symptoms following SARS-CoV-2 infection. This review, therefore, is attempting to highlight the current understanding of the various direct and indirect mechanisms, focusing on the role of neurotropism of SARS-CoV-2, the general pro-inflammatory state, and the pandemic-associated psychosocial stressors in the causality of 'Cognitive COVID.' Neurotropism is associated with various mechanisms including retrograde neuronal transmission via olfactory pathway, a general hematogenous spread, and the virus using immune cells as vectors. The high amounts of inflammation caused by COVID-19, compounded with potential intubation, are associated with a deleterious effect on the cognition as well. Finally, the pandemic's unique psychosocial impact has raised alarm due to its possible effect on cognition. Furthermore, with surfacing reports of post-COVID-vaccination cognitive impairments after vaccines containing mRNA encoding for spike glycoprotein of SARS-CoV-2, we hypothesize their causality and ways to mitigate the risk. The potential impact on the quality of life of an individual and the fact that even a minor proportion of COVID-19 cases developing cognitive impairment could be a significant burden on already overwhelmed healthcare systems across the world make it vital to gather further evidence regarding the prevalence, presentation, correlations, and causality of these events and reevaluate our approach to accommodate early identification, management, and rehabilitation of patients exhibiting cognitive symptoms.

Significance between air pollutants, meteorological factors, and COVID-19 infections: probable evidences in India

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease represents the causative agent with a potentially fatal risk which is having great global human health concern. Earlier studies suggested that air pollutants and meteorological factors were considered as the risk factors for acute respiratory infection, which carries harmful pathogens and affects the immunity. The study intended to explore the correlation between air pollutants, meteorological factors, and the daily reported infected cases caused by novel coronavirus in India. The daily positive infected cases, concentrations of air pollutants, and meteorological factors in 288 districts were collected from January 30, 2020, to April 23, 2020, in India. Spearman's correlation and generalized additive model (GAM) were applied to investigate the correlations of four air pollutants (PM2.5, PM10, NO2, and SO2) and eight meteorological factors (Temp, DTR, RH, AH, AP, RF, WS, and WD) with COVID-19-infected cases. The study indicated that a 10 μg/m3 increase during (Lag0-14) in PM2.5, PM10, and NO2 resulted in 2.21% (95%CI: 1.13 to 3.29), 2.67% (95% CI: 0.33 to 5.01), and 4.56 (95% CI: 2.22 to 6.90) increase in daily counts of Coronavirus Disease 2019 (COVID 19)-infected cases respectively. However, only 1 unit increase in meteorological factor levels in case of daily mean temperature and DTR during (Lag0-14) associated with 3.78% (95%CI: 1.81 to 5.75) and 1.82% (95% CI: -1.74 to 5.38) rise of COVID-19-infected cases respectively. In addition, SO2 and relative humidity were negatively associated with COVID-19-infected cases at Lag0-14 with decrease of 7.23% (95% CI: -10.99 to -3.47) and 1.11% (95% CI: -3.45 to 1.23) for SO2 and for relative humidity respectively. The study recommended that there are significant correlations between air pollutants and meteorological factors with COVID-19-infected cases, which substantially explain the effect of national lockdown and suggested positive implications for control and prevention of the spread of SARS-CoV-2 disease.

Insult to Injury-Potential Contribution of Coronavirus Disease-19 to Neuroinflammation and the Development of HIV-Associated Neurocognitive Disorders

Severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 is responsible for a new coronavirus disease known as coronavirus disease-19 (COVID-19). SARS-CoV-2 reports neurotropic properties and may have neurological implications, and this creates another health burden for people living with HIV. As yet, the impact of COVID-19 on (neuro)inflammation and the development of HIV-associated neurocognitive disorders (HAND) is not fully known. Here, we reviewed preliminary evidence that provides clues that COVID-19 may exacerbate inflammatory mechanisms related to the development of HAND.

A comprehensive review of imaging findings in COVID-19 - status in early 2021

Medical imaging methods are assuming a greater role in the workup of patients with COVID-19, mainly in relation to the primary manifestation of pulmonary disease and the tissue distribution of the angiotensin-converting-enzyme 2 (ACE 2) receptor. However, the field is so new that no consensus view has emerged guiding clinical decisions to employ imaging procedures such as radiography, computer tomography (CT), positron emission tomography (PET), and magnetic resonance imaging, and in what measure the risk of exposure of staff to possible infection could be justified by the knowledge gained. The insensitivity of current RT-PCR methods for positive diagnosis is part of the rationale for resorting to imaging procedures. While CT is more sensitive than genetic testing in hospitalized patients, positive findings of ground glass opacities depend on the disease stage. There is sparse reporting on PET/CT with [18F]-FDG in COVID-19, but available results are congruent with the earlier literature on viral pneumonias. There is a high incidence of cerebral findings in COVID-19, and likewise evidence of gastrointestinal involvement. Artificial intelligence, notably machine learning is emerging as an effective method for diagnostic image analysis, with performance in the discriminative diagnosis of diagnosis of COVID-19 pneumonia comparable to that of human practitioners.

Cerebral venous sinus thrombosis and thrombocytopenia after COVID-19 vaccination - A report of two UK cases

Recent reports have highlighted rare, and sometimes fatal, cases of cerebral venous sinus thrombosis (CVST) and thrombocytopenia following the Vaxzevria vaccine. An underlying immunological mechanism similar to that of spontaneous heparin-induced thrombocytopenia (HIT) is suspected, with the identification of antibodies to platelet factor-4 (PF4), but without previous heparin exposure. This unusual mechanism has significant implications for the management approach used, which differs from usual treatment of CVST. We describe the cases of two young males, who developed severe thrombocytopenia and fatal CVST following the first dose of Vaxzevria. Both presented with a headache, with subsequent rapid neurological deterioration. One patient underwent PF4 antibody testing, which was positive. A rapid vaccination programme is essential in helping to control the COVID-19 pandemic. Hence, it is vital that such COVID-19 vaccine-associated events, which at this stage appear to be very rare, are viewed through this lens. However, some cases have proved fatal. It is critical that clinicians are alerted to the emergence of such events to facilitate appropriate management. Patients presenting with CVST features and thrombocytopenia post-vaccination should undergo PF4 antibody testing and be managed in a similar fashion to HIT, in particular avoiding heparin and platelet transfusions.

nCoV-2019 infection induced neurological outcome and manifestation, linking its historical ancestor SARS-CoV and MERS-CoV: a systematic review and meta-analysis

The first systematic review and meta-analysis to help clinician to identify early signs and symptoms of neurological manifestation in COVID-19 positive patients which will further help in early management of patients. Present systematic review and meta-analysis aimed to discuss the prevalence of neurological involvement of the 2019-nCoV patients and assess the symptomatic trend of events as compared to the 2002 "SARS" and 2012 "MERS" pandemics. The articles were systematically screened through several search engine and databases. The articles published or in preprint were included in the study till 15th May 2020. The systematic review done as per the published literatures which included 31 cross sectional, observational studies and case reports which revealed neurological signs and symptoms in SARS-COV-2 disease. For meta-analysis, we included 09 observational and cross-sectional studies which included COVID-19 positive patients and assessed the predominance of various neurological signs and symptoms in COVID-19 patients with relation to SARS-2002 and MERS-2012. Data was analyzed by using the "MedCalc" Statistical Software version 19.2.6 and reported as pooled prevalence. Standard I2 test was used to analyze the heterogeneity. We have collected and screened about a total 2615articles, finally we have included 31articles for the systematic review and 09 for meta-analysis as per the inclusion/exclusion criteria. The analysis was made as per the prevalence rate of neurological symptoms in COVID-19 positive patients. The cumulative neurological outcome of SARS-2002 and MERS-2012 was assessed to get the trends which was further tried to correlate the events with the current pandemic. During the analysis severity and outcome of neurological manifestations range from simple headache to vague non-focal complaints to severe neurologic impairment associated with seizure or meningitis. Central and peripheral nervous system (CNS/PNS) manifestations were seen during the SARS-2002, MERS-2012 and COVID-19. However, none of the publication had primary or secondary objectives of searching neurological manifestations in the COVID-19 patients and the pathogenic mechanism which will subsequently strengthen the importance to start more prospective clinical trials. The prevalence of neurological signs and symptoms were taken as primary objective. Thereafter, the prevalence of each CNS/PNS symptoms was categorized and their prevalence studied. The selection of Bagheri et al., 2020 may be discussed because they have done the cross-sectional study with the neurological finding and correlated the data with prevalence of the COVID-19 positive patients. The proportion of patients presenting with neurological outcome and clinical/PCR positivity were done. We had searched and followed all the possible online/web source, still the data collection process may remain a limitation of work due to addition of several publications on COVID-19 every day. Due to lack of data of SARS-CoV and MERS-CoV, we have included the case reports, MERS and COVID-19 in CNS/PNS manifestations.

Descriptive and retrospective analysis of diffuse glioma patients with symptomatic SARS-CoV2 infection during the first wave of the pandemic

Background

Little is known about diffuse glioma patients infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2).

Methods

We performed a descriptive and retrospective analysis of 41 diffuse glioma patients with symptomatic SARS-CoV2 infection during the first wave of the COVID-19 pandemic.

Results

Confusion with or without fever was the most common neurological symptom (32%) supporting SARS-CoV2 testing in glioma patients with acute and unexplained confusion. Sixteen patients (39%) died after a median delay of 13 days. While multiple clinical, biological, and pathological features, COVID-19- or diffuse glioma-related, at hospital admission appeared to have a pejorative prognostic impact, none was significantly associated with death. Oncological treatments were interrupted at COVID-19 diagnosis and re-initiated with a median delay of 30 days after the end of COVID-19 symptoms.

Conclusions

Interestingly, our retrospective study describes for the first time the characteristics of a cohort of diffuse glioma patients with symptomatic COVID-19. Diffuse glioma patients with poorly symptomatic COVID-19 did not come to the attention of physicians and were not enrolled in the study skewing the denominator for prognostic analysis. Further studies are warranted to specify prognosis of overall population of diffuse glioma patients with COVID-19, including asymptomatic patients, and interactions of prognostic factors of both COVID-19 and diffuse gliomas.

A case control study to assess effectiveness of measles containing vaccines in preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children

Currently, most licensed vaccines against SARS-CoV-2 infection are approved for adults and not for children. We conducted a test negative case-control study to assess the effectiveness of Measles Containing Vaccines (MCVs) against SARS-CoV-2 infection in Pune, India, in children who were ≥1 year and <18 years of age and were tested for SARS-CoV-2 infection by Reverse transcription polymerase chain reaction (RT-PCR). The enrolled participants included 274 SARS-CoV-2 positive cases (216 vaccinated and 58 unvaccinated) along with 274 SARS-CoV-2 negative controls (265 vaccinated and 9 unvaccinated). Of the 274 cases, 180 (65.7%) were asymptomatic while 94 (34.3%) were symptomatic, all with mild severity. The number of participants with symptomatic SARS-CoV-2 infection was significantly lower in the vaccinated group compared to the unvaccinated group (p < .0001). The unadjusted overall Vaccine Effectiveness (VE) in the vaccinated group compared to unvaccinated group was 87.4% (OR = 0.126, 95% CI of VE: 73.9-93.9) while the adjusted overall VE after adjusting for age and sex was 87.5% (OR = 0.125, 95% CI of VE: 74.2-94.0). MCVs reduced incidence of laboratory confirmed SARS-CoV-2 infection in children. Number of symptomatic cases were also lower in the vaccinated group compared to the unvaccinated group. Results of our study have provided strong preliminary evidence that MCVs have a good effectiveness against SARS-CoV-2 infection in the pediatric population, which needs to be confirmed further through prospective randomized clinical trials.

The chronic neuropsychiatric sequelae of COVID-19: The need for a prospective study of viral impact on brain functioning

INTRODUCTION

The increasing evidence of SARS-CoV-2 impact on the central nervous system (CNS) raises key questions on its impact for risk of later life cognitive decline, Alzheimer's disease (AD), and other dementia.

METHODS

The Alzheimer's Association and representatives from more than 30 countries-with technical guidance from the World Health Organization-have formed an international consortium to study the short-and long-term consequences of SARS-CoV-2 on the CNS-including the underlying biology that may contribute to AD and other dementias. This consortium will link teams from around the world covering more than 22 million COVID-19 cases to enroll two groups of individuals including people with disease, to be evaluated for follow-up evaluations at 6, 9, and 18 months, and people who are already enrolled in existing international research studies to add additional measures and markers of their underlying biology.

CONCLUSIONS

The increasing evidence and understanding of SARS-CoV-2's impact on the CNS raises key questions on the impact for risk of later life cognitive decline, AD, and other dementia. This program of studies aims to better understand the long-term consequences that may impact the brain, cognition, and functioning-including the underlying biology that may contribute to AD and other dementias.

Polyneuropathy following COVID-19 infection: the rehabilitation approach

A range of neurological manifestations associated with COVID-19 have been reported in the literature, but the pathogenesis of these have yet to be fully explained. The majority of cases of peripheral nervous system disease published thus far have shown a symmetrical pattern. In contrast, we describe the case of a patient with asymmetrical predominantly upper-limb sensorimotor polyneuropathy following COVID-19 infection, likely due to a multifactorial pathological process involving critical illness neuropathy, mechanical injury and inflammatory disease. His presentation, management and recovery contribute to the understanding of this complex condition and informs rehabilitation approaches.

Identify. Quantify. Predict. Why Immunologists Should Widely Use Molecular Imaging for Coronavirus Disease 2019

Molecular imaging using PET/CT or PET/MRI has evolved from an experimental imaging modality at its inception in 1972 to an integral component of diagnostic procedures in oncology, and, to lesser extent, in cardiology and neurology, by successfully offering in-vivo imaging and quantitation of key pathophysiological targets or molecular signatures, such as glucose metabolism in cancerous disease. Apart from metabolism probes, novel radiolabeled peptide and antibody PET tracers, including radiolabeled monoclonal antibodies (mAbs) have entered the clinical arena, providing the in-vivo capability to collect target-specific quantitative in-vivo data on cellular and molecular pathomechanisms on a whole-body scale, and eventually, extract imaging biomarkers possibly serving as prognostic indicators. The success of molecular imaging in mapping disease severity on a whole-body scale, and directing targeted therapies in oncology possibly could translate to the management of Coronavirus Disease 2019 (COVID-19), by identifying, localizing, and quantifying involvement of different immune mediated responses to the infection with SARS-COV2 during the course of acute infection and possible, chronic courses with long-term effects on specific organs. The authors summarize current knowledge for medical imaging in COVID-19 in general with a focus on molecular imaging technology and provide a perspective for immunologists interested in molecular imaging research using validated and immediately available molecular probes, as well as possible future targets, highlighting key targets for tailored treatment approaches as brought up by key opinion leaders.

Neurologic Manifestations of COVID-19

Neurological manifestations of novel coronavirus disease (COVID-19) are reported to occur in as much as 37% of the affected patients. These manifestations range from headache and dizziness to altered mental status and consciousness, anosmia, ageusia, sensory disturbances, and stroke. The mechanisms by which the neurological symptoms arise are not yet determined but may either proceed as an indirect consequence of systemic hyperinflammation or result from the direct invasion of the virus to neural and glial cells. The neural invasion can explain both the retrograde pathway of encephalitis and the early manifestation of anosmia by invading the olfactory bulb. Moreover, in the case of attacking the brain stem, it may take part in the early apnea manifestation reported by patients. Additionally, neurotropism of the virus could be the cause of acute hemorrhagic encephalitis. Hyperinflammation can have acute and prolonged effects in the nervous system, such as acute demyelination and predisposition to multiple sclerosis. Moreover, the pro-inflammatory state contributes to hypercoagulation, which in turn could result in cerebrovascular injuries in COVID-19 patients. This chapter would discuss that the neurologic manifestations of the COVID-19 are to be looked at as a multifactorial entangled phenomenon.

SARS-CoV-2 Infection and Guillain-Barré Syndrome: A Review on Potential Pathogenic Mechanisms

Since December 2019, the world has been facing an outbreak of a new disease called coronavirus disease 2019 (COVID-19). The COVID-19 pandemic is caused by a novel beta-coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 infection mainly affects the respiratory system. Recently, there have been some reports of extra-respiratory symptoms such as neurological manifestations in COVID-19. According to the increasing reports of Guillain-Barré syndrome following COVID-19, we mainly focused on SARS-CoV-2 infection and Guillain-Barré syndrome in this review. We tried to explain the possibility of a relationship between SARS-CoV-2 infection and Guillain-Barré syndrome and potential pathogenic mechanisms based on current and past knowledge.

A Dedicated Veno-Venous Extracorporeal Membrane Oxygenation Unit during a Respiratory Pandemic: Lessons Learned from COVID-19 Part II: Clinical Management

(1) Background: COVID-19 acute respiratory distress syndrome (CARDS) has several distinctions from traditional acute respiratory distress syndrome (ARDS); however, patients with refractory respiratory failure may still benefit from veno-venous extracorporeal membrane oxygenation (VV-ECMO) support. We report our challenges caring for CARDS patients on VV-ECMO and alterations to traditional management strategies. (2) Methods: We conducted a retrospective review of our institutional strategies for managing patients with COVID-19 who required VV-ECMO in a dedicated airlock biocontainment unit (BCU), from March to June 2020. The data collected included the time course of admission, VV-ECMO run, ventilator length, hospital length of stay, and major events related to bleeding, such as pneumothorax and tracheostomy. The dispensation of sedation agents and trial therapies were obtained from institutional pharmacy tracking. A descriptive statistical analysis was performed. (3) Results: Forty COVID-19 patients on VV-ECMO were managed in the BCU during this period, from which 21 survived to discharge and 19 died. The criteria for ECMO initiation was altered for age, body mass index, and neurologic status/cardiac arrest. All cannulations were performed with a bedside ultrasound-guided percutaneous technique. Ventilator and ECMO management were routed in an ultra-lung protective approach, though varied based on clinical setting and provider experience. There was a high incidence of pneumothorax (n = 19). Thirty patients had bedside percutaneous tracheostomy, with more procedural-related bleeding complications than expected. A higher use of sedation was noted. The timing of decannulation was also altered, given the system constraints. A variety of trial therapies were utilized, and their effectiveness is yet to be determined. (4) Conclusions: Even in a high-volume ECMO center, there are challenges in caring for an expanded capacity of patients during a viral respiratory pandemic. Though institutional resources and expertise may vary, it is paramount to proceed with insightful planning, the recognition of challenges, and the dynamic application of lessons learned when facing a surge of critically ill patients.