Neurologic Manifestations of Hospitalized Patients With Coronavirus Disease 2019 in Wuhan, China

Translating animal models of SARS-CoV-2 infection to vascular, neurological and gastrointestinal manifestations of COVID-19

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) initiated a global pandemic resulting in an estimated 775 million infections with over 7 million deaths, it has become evident that COVID-19 is not solely a pulmonary disease. Emerging evidence has shown that, in a subset of patients, certain symptoms - including chest pain, stroke, anosmia, dysgeusia, diarrhea and abdominal pain - all indicate a role of vascular, neurological and gastrointestinal (GI) pathology in the disease process. Many of these disease processes persist long after the acute disease has been resolved, resulting in 'long COVID' or post-acute sequelae of COVID-19 (PASC). The molecular mechanisms underlying the acute and systemic conditions associated with COVID-19 remain incompletely defined. Appropriate animal models provide a method of understanding underlying disease mechanisms at the system level through the study of disease progression, tissue pathology, immune system response to the pathogen and behavioral responses. However, very few studies have addressed PASC and whether existing models hold promise for studying this challenging problem. Here, we review the current literature on cardiovascular, neurological and GI pathobiology caused by COVID-19 in patients, along with established animal models of the acute disease manifestations and their prospects for use in PASC studies. Our aim is to provide guidance for the selection of appropriate models in order to recapitulate certain aspects of the disease to enhance the translatability of mechanistic studies.

Optimization of a panel of behavioral tests for use in containment using a golden Syrian hamster model

Golden Syrian hamsters are an often-overlooked model in behavioral testing. While previously utilized for research examining circadian rhythms and mammalian reproduction, they are less common than murine models in both infectious disease and behavioral studies. However, coronavirus disease-19 (COVID-19) quickly pushed hamster modeling to the forefront due to its myriad of advantages over mice in recapitulating human pathology and transmission. At least 10 % of COVID-19 survivors suffer from post-acute sequelae of COVID-19 (PASC), a collection of some 200 sequelae with neurologic sequelae (neuro-PASC) presenting with potentially debilitating symptomology. This presents a clear need for a small animal model that recapitulates human disease with the ability to assess any potential long term neurological changes. We adapted and optimized a panel of behavioral tests from previously accepted murine models utilizing the golden Syrian hamster model for use within biocontainment facilities. Our panel includes grip strength, Porsolt forced swim, and novel object recognition testing to measure muscle fatigue or weakness, depression, and memory loss or cognitive impairment, respectively. Apart from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), this panel of tests is applicable to other pathogens that cause neurologic sequelae, such as Nipah or eastern equine encephalitis viruses, or any other model systems that require the use of hamsters. In this manuscript, we detail the methods for each of these three behavioral tests, how to interpret and analyze the resulting data, and emphasize additional factors for consideration. We also provide baseline data for both male and female golden Syrian hamsters.

Dynamic Molecular Changes in Brain, Lung, and Heart of Hamsters Infected With SARS-CoV-2: Insights From a Severe and Recovery Phase Model

The Global pandemic of coronavirus disease 2019 was initiated by the emergence of severe acute respiratory syndrome coronavirus 2. In addition to conventional pulmonary lesions, a range of neurological injury symptoms have been identified in clinical practice, but the aetiology of neurological disorders linked to SARS-CoV-2 infection remains poorly understood. Syrian hamsters, which are highly susceptible to SARS-CoV-2 infection, exhibit a disease phenotype similar to that observed in human COVID-19 patients. In this study, a hamster model of COVID-19 infection was used to analyze molecular changes in different tissues at various time points post infection with distinct strains using proteomic and phosphoproteomic approaches. Multi-omics analysis showed that SARS-COV-2 infection triggers sustained downregulation of the abundance and phosphorylation levels of neuronal and synapse-associated proteins in the brain, suggesting that neuronal damage persists even during the recovery period. Additionally, infections with SARS-CoV-2 may contribute to the onset of long-term symptoms of COVID-19 by impacting energy metabolism, neurotransmitter release, and synaptic transmission pathways. This study provides a comprehensive molecular profile of hamsters infected with different SARS-CoV-2 strains in different tissues, offering foundational insights into the pathogenic mechanisms of COVID-19.

SARS-CoV2 infection triggers inflammatory conditions and astrogliosis-related gene expression in long-term human cortical organoids

SARS-CoV2, severe acute respiratory syndrome coronavirus 2, is frequently associated with neurological manifestations. Despite the presence of mild to severe CNS-related symptoms in a cohort of patients, there is no consensus whether the virus can infect directly brain tissue or if the symptoms in patients are a consequence of peripheral infectivity of the virus. Here, we use long-term human stem cell-derived cortical organoids to assess SARS-CoV2 infectivity of brain cells and unravel the cell-type tropism and its downstream pathological effects. Our results show consistent and reproducible low levels of SARS-CoV2 infection of astrocytes, deep projection neurons, upper callosal neurons, and inhibitory neurons in 6 months of human cortical organoids. Interestingly, astrocytes showed the highest infection rate among all infected cell populations which led to changes in their morphology and upregulation of SERPINA3, CD44, and S100A10 astrogliosis markers. Further, transcriptomic analysis revealed overall changes in expression of genes related to cell metabolism, astrogliosis and, inflammation and further, upregulation of cell survival pathways. Thus, local and minor infectivity of SARS-CoV2 in the brain may induce widespread adverse effects and lead to the resilience of dysregulated neurons and astrocytes within an inflammatory environment.

Neurological manifestations of acute SARS-CoV-2 infection in a reference hospital in Bahia, Brazil

BACKGROUND

Neurologic manifestations of Coronavirus Disease-19 (COVID-19) have been associated with patients' disease severity and outcome. This study aimed to describe the frequency and characteristics of the neurological manifestations in a group of hospitalized individuals with COVID-19 and their associations with patient outcomes.

METHODS

Patients aged 18 years or older admitted to a local hospital between April and June 2020 with SARS-CoV-2 detected by RT-PCR were included in this retrospective observational study. The characteristics of participants were collected from electronic medical records using a structured questionnaire. A Poisson regression model was used to examine the influence of neurological manifestations on mortality.

RESULTS

A total of 305 participants with COVID-19 were included, with 57.7 % of them presenting neurological symptoms. There were 62 (20.3 %) individuals with acute encephalopathy, with a mean age of 65.5 ± 15.9 years. In this group, higher Prevalence Ratios (PR) of comorbidities (1.6) and severe disease (3.6) were present, predisposing factors for acute encephalopathy. They were also more likely to be admitted to the intensive care unit (3.1) and to die (2.4). The median Neutrophil-Lymphocyte Ratio (NLR) was 7 (Interquartile Range [IQR: 4‒12]). Fifty-two (17 %) participants presented chemosensory dysfunction, with a mean age 53.3 ± 14 years and a lower PR of comorbidity (0.8) than those without. The severe diseases' PR was slightly higher (1.1), but the PR of ICU admission (0.7), and deaths (0.4) was lower. The LNR was 3.8 (IQR: 2.2-7.8). Poisson regression analysis revealed that severe illness (PR = 3.13), cardiopathy (PR = 1.65), acute encephalopathy (PR = 1.49), diabetes (PR = 1.46), and neutrophil-lymphocyte ratio (PR = 1.04) were associated with death. Conversely, having chemosensory disorders (PR = 0.44) and a prolonged hospital stay (PR = 0.96) were associated with survival.

CONCLUSION

Patients with acute encephalopathy had more severe forms of COVID-19 and higher mortality. In contrast, chemosensory dysfunction was associated with milder disease manifestations and a better prognosis.

IL-6 and Olfactory Dysfunction: Focus on Changes, Effects, and Mechanisms

The sense of smell is vital for human life and risk identification. Many diseases can cause olfactory disorders, and early identification and intervention of olfactory disorders are crucial. Currently, the diagnosis of olfactory disorders in clinical practice mostly relies on subjective visual analog scale (VAS) evaluations, expensive and complex imaging, and neurophysiological examinations, which lead to poor patient compliance and low completion rates. Therefore, there is an urgent need to identify novel, objective, easily detectable biological indicators. Interleukin-6 (IL-6) is an inflammatory factor that is closely associated with olfactory dysfunction in various diseases. However, the role of IL-6 in the occurrence and development of olfactory disorders is not yet clear, which limits its clinical application. This article reviews the changes and possible mechanisms of IL-6 in various diseases associated with olfactory disorders, with the aim of providing a reference for the clinical application of IL-6 as a biomarker for olfactory disorders and promoting an in-depth exploration of its mechanism in the occurrence and development of olfactory disorders.

Decoding mechanisms and protein markers in lung-brain axis

BACKGROUND

The lung-brain axis represents a complex bidirectional communication network that is pivotal in the crosstalk between respiratory and neurological functions. This review summarizes the current understanding of the mechanisms and protein markers that mediate the effects of lung diseases on brain health.

MAIN FINDINGS

In this review, we explore the mechanisms linking lung injury to neurocognitive impairments, focusing on neural pathways, immune regulation and inflammatory responses, microorganism pathways, and hypoxemia. Specifically, we highlight the role of the vagus nerve in modulating the central nervous system response to pulmonary stimuli; Additionally, the regulatory function of the immune system is underscored, with evidence suggesting that lung-derived immune mediators can traverse the blood-brain barrier, induce neuroinflammation and cognitive decline; Furthermore, we discuss the potential of lung microbiota to influence brain diseases through microbial translocation and immune activation; Finally, the impact of hypoxemia is examined, with findings indicating that it can exacerbate cerebral injury via oxidative stress and impaired perfusion. Moreover, we analyze how pulmonary conditions, such as pneumonia, ALI/ARDS, and asthma, contribute to neurological dysfunction. Prolonged mechanical ventilation can also contribute to cognitive impairment. Conversely, brain diseases (e.g., stroke, traumatic brain injury) can lead to acute respiratory complications. In addition, protein markers such as TLR4, ACE2, A-SAA, HMGB1, and TREM2 are crucial to the lung-brain axis and correlate with disease severity. We also discuss emerging therapeutic strategies targeting this axis, including immunomodulation and microbiome engineering. Overall, understanding the lung-brain interplay is crucial for developing integrated treatment strategies and improving patient outcomes. Further research is needed to elucidate the molecular mechanisms and foster interdisciplinary collaboration.

The age-dependent neuroglial interaction with peripheral immune cells in coronavirus-induced neuroinflammation with a special emphasis on COVID-19

Neurodegenerative diseases are chronic progressive disorders that impair memory, cognition, and motor functions, leading to conditions such as dementia, muscle weakness, and speech difficulties. Aging disrupts the stringent balance between pro- and anti-inflammatory cytokines, increasing neuroinflammation, which contributes to neurodegenerative diseases. The aging brain is particularly vulnerable to infections due to a weakened and compromised immune response and impaired integrity of the blood-brain barrier, allowing pathogens like viruses to trigger neurodegeneration. Coronaviruses have been linked to both acute and long-term neurological complications, including cognitive impairments, psychiatric disorders, and neuroinflammation. The virus can induce a cytokine storm, damaging the central nervous system (CNS) and worsening existing neurological conditions. Though its exact mechanism of neuroinvasion remains elusive, evidence suggests it disrupts the blood-brain barrier and triggers immune dysregulation, leading to persistent neurological sequelae in elderly individuals. This review aims to understand the interaction between the peripheral immune system and CNS glial cells in aged individuals, which is imperative in addressing coronavirus-induced neuroinflammation and concomitant neurodegeneration.

Guinea Pigs Are Not a Suitable Model to Study Neurological Impacts of Ancestral SARS-CoV-2 Intranasal Infection

Neurological symptoms involving the central nervous system (CNS) and peripheral nervous system (PNS) are common complications of acute COVID-19 as well as post-COVID conditions. Most research into these neurological sequalae focuses on the CNS, disregarding the PNS. Guinea pigs were previously shown to be useful models of disease during the SARS-CoV-1 epidemic. However, their suitability for studying SARS-CoV-2 has not been experimentally demonstrated. To assess the suitability of guinea pigs as models for SARS-CoV-2 infection and the impact of SARS-CoV-2 infection on the PNS, and to determine routes of CNS invasion through the PNS, we intranasally infected wild-type Dunkin-Hartley guinea pigs with ancestral SARS-CoV-2 USA-WA1/2020. We assessed PNS sensory neurons (trigeminal ganglia, dorsal root ganglia), autonomic neurons (superior cervical ganglia), brain regions (olfactory bulb, brainstem, cerebellum, cortex, hippocampus), lungs, and blood for viral RNA (RT-qPCR), protein (immunostaining), and infectious virus (plaque assay) at three- and six-days post infection. We show that guinea pigs, which have previously been used as a model of SARS-CoV-1 pulmonary disease, are not susceptible to intranasal infection with ancestral SARS-CoV-2, and are not useful models in assessing neurological impacts of infection with SARS-CoV-2 isolates from the early pandemic.

Post-acute sequelae SARS-CoV-2 infection and neuropathic pain: a narrative review of the literature and future directions

PURPOSE OF REVIEW

Neuropathic pain is a recognized and debilitating symptom of SARS-CoV-2 infection across acute, post-acute, and long-COVID phases. Initially emerging as acute or subacute symptoms, these neuropathic manifestations can evolve into chronic conditions, with approximately 10% of all SARS-CoV-2 cases (estimated 65 million individuals globally) developing post-acute SARS-CoV-2 (PASC) neuropathic sequalae. Given the limited literature specifically addressing neuropathic pain related to PASC, a deeper understanding is needed to improve management and reduce patient burden.

RECENT FINDINGS

PASC symptoms are associated with disease severity, elevated body mass indexes, preexisting psychological conditions, and addiction history. Sex differences appear to influence prevalence, and the multisystem nature of PASC complicates symptom presentation, with mood disorders, fatigue, and cognitive dysfunction contributing to altered pain perception. Proposed mechanisms include immune dysregulation, persistent viral protein effects, and neuroanatomical changes. Management typically involves a multimodal approach.

SUMMARY

This review examines SARS-CoV-2 neuropathic pain across the illness trajectory, examining its pathophysiology, prevalence, and treatment. It highlights the potential for subacute neuropathic symptoms to become chronic and calls for future research to refine long-term management strategies and assess broader healthcare implications.

Effects of coronavirus disease 2019 on the incidence, mortality, and prognosis of ischemic stroke: a systematic review and meta-analysis

Objective

The objective of this study was to conduct a systematic review on the effect of coronavirus disease 2019 (COVID-19) on the incidence, mortality, and prognosis of ischemic stroke. The systematic review also ascertained the relationship between COVID-19 and the Trial of Org 10,172 in Acute Stroke Treatment (TOAST) typing of ischemic stroke, as well as the risk factors for ischemic stroke in patients with COVID-19.

Methods

The relevant literature between COVID-19 and ischemic stroke incidence, mortality, and prognosis up to January 2024 were systematically reviewed. Searches were carried out PubMed, Embase, Web of Science, and Cochrane databases. Utilizing the Meta-analysis of observational studies in epidemiology (MOOSE) declaration list, a systematic review and meta-analysis were carried out. Heterogeneity and publication bias were assessed.

Results

Twenty-one studies encompassed 505,864 participants across 13 countries. In total, 1.1% of patients with COVID-19 infection had an ischemic stroke (odds ratio [OR], 0.011; 95% confidence interval [CI], 0.007-0.017; p < 0.001). COVID-19 was related to in-hospital mortality (OR, 2.76; 95% CI, 1.90-4.02; p < 0.001), mortality 3 months following the beginning of an ischemic stroke (OR, 2.54; 95% CI, 1.80-3.58; p < 0.001), and modified Rankin scale (mRS) score ≤2 at hospital discharge (OR, 0.62; 95% CI, 0.54-0.72; p < 0.001). mRS ≤ 2 at 3 months after the onset of ischemic stroke did not show any correlation significantly with COVID-19 (OR, 0.67; 95% CI, 0.43-1.06; p = 0.086). Longer hospital stays (OR, 0.13; 95% CI, 0.06-0.20; p < 0.001) and increased incidence of large-artery atherosclerosis and small-vessel disease phenotypes of ischemic stroke were observed in patients with both COVID-19 and ischemic stroke (p < 0.05). In patients with COVID-19, ischemic stroke was substantially linked with hypertension, diabetes, hyperlipidemia, smoking, atrial fibrillation, coronary artery disease, chronic kidney disease, and chronic obstructive pulmonary disease (p < 0.05).

Conclusion

COVID-19 is linked with increased incidence and mortality rates for ischemic stroke, as well as a worsening prognosis for the condition. With the data obtained from this study, targeted strategies to prevent and treat ischemic stroke in the context of the COVID-19 can be developed.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/view/CRD42024524016, identifier: CRD42024524016.

A pilot study on the effect of SARS-CoV-2 spike protein on IL-1β-mediated inflammation in peripheral blood immune cells from AIED patients

BACKGROUND

Immune-mediated hearing loss (IMHL) patients (comprised of autoimmune inner ear disease (AIED) and sudden sensorineural hearing loss (SSNHL)) may be at higher risk for hearing loss following Coronavirus disease (COVID-19) infection and/or vaccination.

METHODS

We compared inflammatory cytokine expression in response to SARS-CoV2 spike protein between two groups of patients with IMHL: IMHL patients that temporally demonstrated worsening SNHL following COVID vaccination or infection as compared to IMHL patients with worsening SNHL unrelated to COVID exposure: (IMHL-COVID ( +)) (n = 11) (IMHL-COVID (-)) (n = 10). In these two groups, we treated isolated PBMCs with increasing amounts of SARS-CoV-2 spike protein and compared responses to stimulation with positive and negative controls.

RESULTS

Peripheral Blood Mononuclear Cells (PBMC) from IMHL-COVID ( +) patients had increased expression and release of both IL-1β and IL-6 in response to spike protein as compared to IMHL-COVID (-) patients. However, when the IMHL-COVID ( +) group was broken down into AIED patients compared to SSNHL, it became apparent that the greatest responses were from the AIED patients (p < 0.005 for IL-6 mRNA expression and p < 0.003 for IL-6 release when compared between any two similar groups using Wilcoxon Rank-Sum Test). When we broke down the COVID ( +) group to infection versus vaccination, the immune responses in the infection group (N = 3 AIED, 1 SSNHL) were stronger.

CONCLUSIONS

COVID-19 exposure with reported changes in hearing sensitivity in IMHL patients resulted in pro-inflammatory responses in response to spike protein. The inflammatory responses were greatest in AIED patients, and greater following infection rather than vaccination. Therefore, based on these studies, we would recommend AIED patients take additional precautions to avoid COVID exposure. Furthermore, we do recommend COVID vaccination during periods of hearing stability, as the immune responses are even more robust in response to infection in this vulnerable group.

Viral agents in neuromuscular pathology

In recent years, viral infections have been increasingly identified as major players in neuromuscular pathologies. This chapter presents an overview of the evidence and future directions for virus-induced neuromuscular disorders. Information is integrated on the global burden of these diseases related to epidemiology, clinical features, diagnosis, treatment, and preventive strategies was integrated. Responsible viruses include enteroviruses, flaviviruses, herpesviruses, and emerging pathogens such as SARS-CoV-2. It represents a broad spectrum of neuromuscular disorders, including Guillain-Barré syndrome, viral myositis, and critical illness neuropathy/myopathy. The book chapter discusses different diagnostic approaches, therapy strategies, and rehabilitation methods, in addition to early intervention and preventive measures. This has led to new insights into novel therapies, unmet research needs, and future perspectives on viral neuromuscular disorders. This chapter demonstrates that supporting both clinical care and patient management with clinical research entails a profound understanding of the difficult interactions between the viruses concerned and the neuromuscular system.

Exploring the impact of acute SARS-CoV-2 infection on headache pattern in patients with migraine: A novel Bayesian analysis

OBJECTIVES

To analyze headache and migraine dynamics around severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

BACKGROUND

Headache is a common symptom of SARS-CoV-2 infection, which caused the coronavirus disease 2019 (COVID-19) pandemic. However, the daily changes in headache patterns in patients with migraine during the infection are unclear.

METHODS

This study is a post hoc and retrospective study of patients with migraine and documented COVID-19 diagnoses and headache diaries from a large prospective migraine cohort that consecutively enrolls eligible patients. Patients' characteristics, headache and migraine patterns, and vaccination data were retrieved. Change points in daily headache or migraine rates of this cohort were identified from 28 days before (day -28) to 28 days after (day 28) the infection. We calculated and compared the weekly headache and migraine days of individual patients during pre-infection, infection, and post-infection periods based on the change points. We further categorized patients into those with increased headache days and those without to investigate if vaccinations affected the headache patterns by comparing the pre- and post-infection headache days.

RESULTS

A total of 463 patients, 370 (79.9%) females, with an age (mean ± standard deviation) of 41.5 ± 11.9 years, were enrolled. A total of 26,391 diary days were analyzed. The change-point algorithm identified changes in headache rates on day -4 (95% credible interval: -5.0, -1.2) and day 12 (95% credible interval: 7.6, 17.0). For migraine attacks, the change points were day -2 (95% credible interval: -4.9, -0.8) and day 11 (95% credible interval: 7.6, 17.2). After the grouping based on these change points, we found that the weekly headache days (mean ± standard error of the mean) increased from 1.5 ± 0.1 days during pre-infection to 1.8 ± 0.1 days during acute infection and recovered to 1.6 ± 0.1 days after infection. The weekly migraine days increased from 1.0 ± 0.1 day to 1.3 ± 0.1 days during acute infection and recovered to 1.1 ± 0.1 days. Female patients and those older than 40 had more abrupt changes in headache and migraine patterns. There was no impact of vaccinations on the headache pattern regardless of the type or dose of the vaccinations or the intervals between the last vaccination and the COVID-19 diagnosis.

CONCLUSION

We demonstrated that the headache and migraine rates among individuals with migraine escalated during the early stage of SARS-CoV-2 infection and returned to baseline along with systemic viral clearance.

Fatal Acute Necrotizing Encephalopathy in a 17-Year-Old Girl with COVID-19: A Case Report

BACKGROUND Acute necrotizing encephalopathy (ANE) is a severe and rapidly progressive form of encephalopathy predominantly observed in children following various systemic infections. Although rare, cases of ANE have been increasingly associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This report details a fatal case of ANE in a 17-year-old girl diagnosed with coronavirus disease 2019 (COVID-19), emphasizing the critical need for early diagnosis and prompt intervention to improve clinical outcomes. CASE REPORT A previously healthy 17-year-old girl presented with a 3-day history of fever followed by onset of seizures and consciousness disorders after testing positive for SARS-CoV-2. Cranial magnetic resonance imaging (MRI) revealed bilateral symmetrical thalamus, which is a typical imaging presentation of ANE. Cerebrospinal fluid (CSF) examination revealed a normal cell count. Differential diagnoses such as acute disseminated encephalomyelitis (ADEM) and Leigh syndrome were excluded, leading to a diagnosis of ANE. Despite aggressive treatment, including respiratory support, intravenous immunoglobulin, and high-dose glucocorticoids, the patient's condition deteriorated rapidly, resulting in death the following day. CONCLUSIONS ANE is a rare but devastating condition in adolescents, particularly following viral infections such as COVID-19. It should be considered in patients presenting with seizures and progressive consciousness disorders after viral infection. Urgent neuroimaging and lumbar puncture are essential for diagnosis. Early recognition, immunotherapy, and aggressive management are crucial to mitigate the high mortality associated with this severe neurological disorder.

Predictors of Mortality and Neurological Complications in a Large Cohort of Patients With COVID-19: A Retrospective Single-Center Cohort Study

OBJECTIVES

This study aimed to investigate the association between the baseline clinical and laboratory characteristics of patients with COVID-19 and their risk of subsequent development of neurological complications and mortality.

METHODS

This retrospective, single-center cohort study included patients with COVID-19 who presented to the Emergency Department of Razi Hospital. Patients' charts were reviewed to collect baseline clinical and laboratory data.

RESULTS

Of 2205 patients with COVID-19, 1473 (66.8%) developed various neurological complications in addition to other symptoms. Among the 168 patients who died, 66.66%, 43.5%, and 25% had a history of neurological disorders, encephalopathy, and stroke, respectively. Disease severity was significantly associated with comorbidities, hypoxemia, hypoalbuminemia, hypophosphatemia, elevated ESR, hypomagnesemia, stroke, and encephalopathy (P<0.05). The risk of death remained strongly linked to older age, comorbidities, severe infection, ICU admission, and extended hospitalization (P<0.05), even after adjustments, indicating they are potential confounders for other variables. More importantly, in non-critically ill patients, there was no significant association between the risk of death and hypoxemia, anemia, thrombocytopenia, hypomagnesemia, stroke, and encephalopathy (P>0.05). Moreover, the association between encephalopathy and other factors was greatly influenced by disease severity. Nonetheless, older age, comorbidities, and anemia remained significant predictors of stroke even after adjusting for confounders (P<0.05).

CONCLUSIONS

The high rates of neurological disorders among deceased patients with COVID-19 underscores the need for early prediction and management of these complications. Moreover, neurological disorders were linked to an increased risk of death because they tend to be present in critically ill patients admitted to the ICU with extended hospitalization.

Long COVID and Associated Factors Among Chinese Residents Aged 16 Years and Older in Canada: A Cross-Sectional Online Study

As the COVID-19 pandemic evolved, long COVID emerged as a significant threat to public health, characterized by one or more persistent symptoms impacting organ systems beyond 12 weeks of infection. Informative research has been derived from assessments of long COVID among the Chinese populace. However, none of these studies considered the COVID-19 experience of Chinese residents in Canada. Objectives: We aimed to fill this literature gap by delineating the long COVID experience, prevalence, and associated factors among a sample of Chinese residing in Canada during the pandemic. Methods: The present study employed a cross-sectional online survey questionnaire distributed to a sample of Canadian Chinese using a convenience sampling procedure from 22 December 2022 to 15 February 2023. Respondents were probed for sociodemographic background and health-, COVID-, and vaccine-related characteristics. Logistic LASSO regression was used for model building, and multivariate logistic regression was used to identify factors associated with developing long COVID. Results: Among 491 eligible participants, 63 (12.83%) reported experiencing long COVID with a mean duration of 5.31 (95% CI: 4.06-6.57) months and major symptoms including difficulty concentrating (21.67%), pain/discomfort (15.00%), as well as anxiety/depression (8.33%). Our final model identified significant associations between long COVID and two or more COVID-19 infections (OR = 23.725, 95% CI: 5.098-110.398, p < 0.0001), very severe/severe symptoms (OR = 3.177, 95% CI: 1.160-8.702, p = 0.0246), over-the-counter medicine (OR = 2.473, 95% CI: 1.035-5.909, p = 0.0416), and traditional Chinese medicine (OR = 8.259, 95% CI: 3.016-22.620, p < 0.0001). Further, we identified a significant protective effect of very good/good health status (OR = 0.247, 95% CI: 0.112-0.544, p = 0.0005). Conclusions: Long COVID effected a notable proportion of Canadian Chinese for a prolonged period during the COVID-19 pandemic. Our findings underscore the importance of preexisting health status and reinfection prevention when managing long COVID. Moreover, our work indicates an association between using over-the-counter medicine or traditional Chinese medicine and long COVID experience among Canadian Chinese.

Functional connectivity of default mode network in non-hospitalized patients with post-COVID cognitive complaints

Introduction

Neurologic impairment is common in patients with acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. While patients with severe COVID have a higher prevalence of neurologic symptoms, as many as one in five patients with mild COVID may also be affected, exhibiting impaired memory as well as other cognitive dysfunctions.

Methods

To characterize the effect of COVID on the brain, the current study recruited a group of adults with post-COVID cognitive complaints but with mild, non-hospitalized cases. They were then evaluated through formal neuropsychological testing and underwent functional MRI of the brain. The participants in our study performed nearly as expected for cognitively intact individuals. Additionally, we characterized the functional connectivity of the default mode network (DMN), which is known for cognitive functions including memory as well as the attention functions involved in normal aging and degenerative diseases.

Results

Along with the retention of functional connectivity in the DMN, our results found the DMN to be associated with neurocognitive performance through region-of-interest and whole-brain analyses. The connectivity between key nodes of the DMN was positively correlated with cognitive scores (r = 0.51, p = 0.02), with higher performers exhibiting higher DMN connectivity.

Discussion

Our findings provide neuroimaging evidence of the functional connectivity of brain networks among individuals experiencing cognitive deficits beyond the recovery of mild COVID. These imaging outcomes indicate expected functional trends in the brain, furthering understanding and guidance of the DMN and neurocognitive deficits in patients recovering from COVID.

Characterizing stroke presenting to a regional referral hospital before and during the COVID-19 pandemic in Uganda: a retrospective analysis

INTRODUCTION

Stroke, a leading cause of global morbidity and mortality, disproportionately impacts low and middle-income countries, particularly in sub-Saharan Africa (SSA) which reports the highest stroke burden. The COVID-19 pandemic further complicated this situation, emerging as a significant stroke risk factor. The pandemic also disrupted healthcare systems worldwide, affecting stroke management and care accessibility, and leading to deteriorated conditions in stroke patients upon hospital admission. In this pre/during COVID-19 pandemic analysis of acute stroke cases presenting to a Ugandan hospital, we investigated the relationship between stroke admissions, management and treatment outcomes.

METHODS

This was a retrospective medical record review in which we analyzed medical charts of stroke patients admitted to Mbarara Regional Referral Hospital in 2019 (pre-COVID-19) and 2020 (during COVID-19). Socio-demographic data, stroke subtypes, medical history, and physical examination findings were extracted from the hospital records. Data analysis was performed using R-Studio, employing descriptive statistics and inferential analyses to compare stroke characteristics and outcomes across the two periods.

RESULTS

Data from 175 stroke patients was analyzed, with higher admission numbers in 2020 (69.7%), but a slightly higher mortality rate in 2019 as compared to 2020 (22.6% versus 18.9%, p = 0.711). A significant increase in acute ischemic stroke cases was observed in 2020, with no significant differences in stroke severity or functional ability between the two years. Clinical parameters such as admission oxygen saturation, blood sugar, temperature, and Glasgow Coma Scale (GCS) score, along with complications like aspiration pneumonia and infections, correlated with mortality. There was no significant difference in survival probability between pre- and during-pandemic periods. Admission GCS, pulse rate, and aspiration pneumonia were significant predictors of 14-day in-hospital mortality.

CONCLUSIONS

The surge in acute ischemic stroke cases during the pandemic highlights the need for robust stroke care systems, especially in high-burden regions like SSA. Some key predictors of mortality are potentially modifiable, suggesting that early intervention and vigilant monitoring of risk parameters could improve survival rates. Findings also highlight the need for tailored care strategies and health system improvements especially during public health emergencies to enhance patient outcomes.

TRIAL REGISTRATION

Not Applicable.

Neurologic features in hospitalized patients with COVID-19: a prospective cohort in a catalan hospital

OBJECTIVES

To study the prevalence and timing of neurological manifestations, including cognitive involvement, in patients hospitalized for Coronavirus disease 2019 (COVID-19). To analyze the pathogenic mechanisms and any association they have with disease severity.

METHODS

Longitudinal cohort study with prospective follow-up of patients who required hospitalization. Patients under 65 who had no pre-existing cognitive impairment and did not require an ICU stay were evaluated 3 and 12 months after discharge using a battery of neuropsychological tests.

RESULTS

Of 205 patients hospitalized for COVID-19, 153 (74.6%) presented with neurological manifestations. The most frequent were myalgia (32.7%), headache (31.7%), dysgeusia (29.2%), and anosmia (24.9%). Patients with more severe illness at the time of hospitalization presented fewer neurological manifestations. Of the 62 patients who underwent neuropsychological examination 3 months after discharge, 22.6% had impaired attention, 19.4% impaired working memory, 16.1% impaired learning and retrieval, 9.7% impaired executive functions, and 8.2% impaired processing speed. Patients with anosmia also presented with more headache (OR 5.45; p < 0.001) and greater risk of working memory impairment (OR 5.87; p 0.03). At follow-up 12 months after hospital discharge, 14.3% of patients still showed impaired attention, 2.4% impaired working memory, 2.5% impaired executive functions, and 2.5% impaired processing speed.

DISCUSSION

Neurological manifestations are common in patients hospitalized for COVID-19 regardless of severity. The high prevalence of anosmia and its association with headache and working memory impairment at 3 months, suggest potential direct or indirect damage to the prefrontal cortex via invasion of the olfactory bulb by COVID-19.

Neuroinflammation in Severe COVID-19: The Dynamics of Inflammatory and Brain Injury Markers During Hospitalization

Patients with COVID-19 can develop excessive inflammation in the brain and consequent neurological complications. The aim of this study was to evaluate the inflammatory, endothelial and brain injury markers in hospitalized COVID-19 patients and compare those with or without neurological symptoms. A total of 30 intensive care unit (ICU) COVID-19 patients were allocated into COVID-19 (without neurological symptoms) or neuro-COVID-19 (with neurological symptoms) groups. Patients with respiratory infection symptoms but negative for COVID-19 were included as a control group. Peripheral blood samples were collected at hospital admission (T1) (controls and ICU patients) and during hospitalization (T2: last 72 h before hospital discharge or in-hospital death) (ICU COVID-19 patients) to analyze inflammatory markers. Higher ICAM-1, CCL26 and VEGF at T1 were identified in both COVID-19 groups compared with control. Neuro-COVID-19 patients presented lower systemic BDNF levels compared with the control group and increased S100B compared with the control and COVID-19 groups. BDNF levels in survivors were lower in the neuro-COVID-19 group compared to the COVID-19 group, while S100B were higher, regardless of the outcome. In addition, all COVID-19 patients presented increased ICAM-1 and CCL26 levels over the hospitalization period (T2 > T1). Furthermore, S100B, ICAM-1, CCL26 and VEGF levels increased in relation to T1 in neuro-COVID-19 patients, with S100B and CCL26 being significantly higher in relation to the COVID-19 group. In conclusion, high levels of brain injury biomarkers were found in patients with neuro-COVID-19, indicating neuroinflammatory and consequent brain injury in the last 72 h of hospitalization.

Effect of the nurse-led Hospital Elder Life Program on delirium reduction among delirious patients with COVID-19: A randomized clinical trial

BACKGROUND

Infectious diseases, such as COVID-19, are high-risk factors for delirium. However, the implementation of nonpharmacological interventions faces major challenges during an infectious disease pandemic.

AIMS

To evaluate the effect of the nurse-led Hospital Elder Life Program (NL-HELP) on delirium reduction among delirious patients with COVID-19.

DESIGN

A single-blind randomized clinical trial.

METHODS

This study recruited 122 delirious patients with COVID-19 from internal medicine wards at West China Hospital in China between January 30 and March 31, 2023. Participants were randomized to the NL-HELP group (n = 62) or the usual care group (n = 60). Patients in the intervention group received the NL-HELP protocol three times daily for 7 days. Patients in the control group received usual care. The primary outcome was the absence/presence of delirium during the intervention period measured by the 3-min Diagnostic Confusion Assessment Method.

RESULTS

Fewer patients remained delirious in the NL-HELP group than in the control group. There were significantly more delirium-free days in the NL-HELP group than in the usual care group. There were no statistically significant differences between the two groups in terms of delirium severity, length of hospital stay, delirium at 30 days after discharge, 30-day readmission, 30-day mortality, physical function or quality of life.

CONCLUSIONS

This study demonstrated that NL-HELP could reduce the presence of delirium in delirious patients. No effect was observed in terms of shortening the length of hospital stay, reducing 30-day mortality, or improving quality of life.

IMPACT

NL-HELP may be effective in reducing the presence of delirium in delirious patients. Further research is needed to determine whether the NL-HELP can improve patient outcomes (e.g. mortality and quality of life) in a larger study.

PATIENT OR PUBLIC CONTRIBUTION

Caregivers of delirious patients were invited to provide intervention strategies to prevent or abate delirium, including environmental management, orientation communications and identification of alert signs.

TRIAL REGISTRATION

This study was prospectively registered at the Chinese Clinical Trial Registry (https://www.chictr.org.cn/) Identifier: ChiCTR2300067874.

Significance of Neurological Manifestations and Their Association With Clinical Outcomes in Hospitalized COVID-19 Patients in Bandar Abbas, Iran: A Cross-Sectional Study

Background

Neurological manifestations are increasingly recognized in COVID-19 patients, yet their prevalence and clinical significance remain understudied. This study aimed to determine the incidence and significance of neurological symptoms and their associations with demographic, clinical, and laboratory parameters in hospitalized COVID-19 patients.

Method

A cross-sectional study was conducted at Shahid Mohammadi Hospital, Bandar Abbas, Iran, from February 2020 to February 2021. A total of 540 RT-PCR-confirmed COVID-19 patients were included. Data on demographics, comorbidities, clinical symptoms, neurological manifestations (e.g., myalgia, headache, smell/taste impairment, dizziness), and laboratory findings were collected. Statistical analyses were performed using SPSS version 20.

Results

Myalgia was the most common neurological symptom (33.9%), followed by headache (16.7%), smell/taste impairment (10.2%), and dizziness (6.9%). A significantly higher prevalence of myalgia and smell/taste impairment was observed in patients under 50 years old (p ≤ 0.05). Patients with myalgia also had a significantly higher prevalence of prior chronic heart disease and were more likely to experience concurrent smell/taste impairment (p ≤ 0.05). Notably, while some inflammatory markers were elevated in both patients with and without myalgia and smell/taste impairment, the increase was significantly less pronounced in those exhibiting these neurological symptoms (p ≤ 0.05). Additionally, patients with headache and smell/taste impairment were less frequently admitted to the ICU (p ≤ 0.05). A statistically significant co-occurrence was also observed among the presence of headache, dizziness, and smell/taste impairment in COVID-19 patients (p ≤ 0.05).

Conclusion

Neurological symptoms are prevalent in COVID-19 patients and may serve as markers of disease severity and progression. Recognizing these manifestations can aid in early diagnosis and inform tailored management strategies. Further research with larger, diverse populations and advanced diagnostic tools is needed to validate these findings and better understand the mechanisms underlying COVID-19-related neurological involvement.

Altered brain glucose metabolism in COVID-19 disease: an activation likelihood estimation meta-analysis of PET studies

COVID-19 disease, caused by the SARS-CoV-2 virus, has significantly altered modern society and lifestyles. We investigated its impact on brain glucose metabolism by meta-analyzing existing studies that utilized 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scans of the brain. We conducted a systematic search of MEDLINE and EMBASE databases from inception to August 2024 for English-language publications using the keywords "positron emission tomography", and "COVID-19". We included original research articles that reported changes in brain glucose metabolism following COVID-19 disease. ALE values from these studies were aggregated and tested against a null hypothesis that anticipated a random distribution of ALE values, which proved to be significantly higher than chance. We identified nine papers that met our inclusion criteria. Significant increases in brain glucose metabolism were noted in the left anterior cingulate gyrus, right thalamus, and brainstem. In children with COVID-19 disease, decreased glucose metabolism was observed in the right and left cerebellum, left amygdala/hippocampus, left anterior cingulate gyrus, and right amygdala. In adults with COVID-19 disease, decreased metabolism was seen in the right temporal lobe, brainstem (acute phase), left occipital lobe, left and right temporal lobe (chronic phase). In conclusion, COVID-19 disease impacts brain glucose metabolism, typically manifesting as areas of decreased metabolism in 18F-FDG PET scans, though increases are also observed. These changes in metabolism vary with the patient's age and the time elapsed between the diagnosis of COVID-19 disease and the PET scan.

Impact of Severe COVID-19 on Accelerating Dementia Onset: Clinical and Epidemiological Insights

Importance

Severe COVID-19 infection has been associated with neurological complications, but its role in accelerating cognitive decline remains unclear.

Objective

To determine whether individuals hospitalized for severe COVID-19 exhibit a higher incidence of new onset cognitive impairment compared to those hospitalized for other conditions.

Design

A retrospective study emulating a target trial using Mass General Brigham electronic health records (March 2020-August 2024). The causal effect of COVID-19 hospitalization was estimated via cumulative incidence functions accounting for the competing risk of death.

Setting

Multicenter hospital-based study across the Mass General Brigham healthcare system.

Participants

A total of 221613 hospitalized patients met the eligibility criteria, including 6454 (2.0%) admitted due to COVID-19 and 215159 (98.0%) for all other conditions. Patients were excluded if they had less than three months of follow-up (due to censoring, cognitive impairment, or death), were younger than 55 years at baseline, or had no prior visit to Mass General Brigham in the year before baseline.

Main Outcomes and Measures

The primary outcome was new-onset cognitive impairment, identified via ICD codes and dementia medication prescriptions. The primary analysis estimated the hazard ratio for cognitive impairment with COVID-19 hospitalization relative to other hospitalizations, along with the risk difference at 4.5 years estimated via cumulative incidence functions. Inverse propensity score weighting was used to balance covariates (age, sex, comorbidities, hospitalization period).

Results

Among eligible patients (mean [SD] age, 69.55 [9.42] years, 55% female), those hospitalized for COVID-19 were significantly older and had more comorbidities (p < 0.05). COVID-19 hospitalization was associated with a higher risk of developing cognitive impairment (Hazard Ratio: 1.14 [95% CI: 1.02-1.30], P = 0.018). At 4.5 years, the cumulative incidence of cognitive impairment was 12.5% [95% CI: 11.3-13.5] in the COVID-19 group, compared to 11.6% [95% CI: 11.1-12.1] in the non-COVID-19 group.

Conclusions and Relevance

Severe COVID-19 infection was associated with an elevated risk of developing clinically recognized cognitive impairment. Future studies are needed to validate findings in other health care settings. Early screening and intervention for cognitive decline may help optimize long-term outcomes for COVID-19 patients.

Role of toll-like receptors in post-COVID-19 associated neurodegenerative disorders?

In the intricate realm of interactions between hosts and pathogens, Toll-like receptors (TLRs), which play a crucial role in the innate immune response, possess the ability to identify specific molecular signatures. This includes components originating from pathogens such as SARS-CoV-2, as well as the resulting damage-associated molecular patterns (DAMPs), the endogenous molecules released after cellular damage. A developing perspective suggests that TLRs play a central role in neuroinflammation, a fundamental factor in neurodegenerative conditions like Alzheimer's and Parkinson's disease (PD). This comprehensive review consolidates current research investigating the potential interplay between TLRs, their signaling mechanisms, and the processes of neurodegeneration following SARS-CoV-2 infection with an aim to elucidate the involvement of TLRs in the long-term neurological complications of COVID-19 and explore the potential of targeting TLRs as a means of implementing intervention strategies for the prevention or treatment of COVID-19-associated long-term brain outcomes.

Convergence of COVID-19 and recurrent stroke: In-hospital mortality risks explored

This editorial comments on the article by Desai et al, which investigates the impact of coronavirus disease 2019 (COVID-19) on in-hospital mortality among patients with recurrent stroke using data from the 2020 National Inpatient Sample. The findings reveal significantly higher mortality rates in COVID-19-positive patients compared to non-COVID-19 patients, particularly among middle-aged individuals, males, and ethnic minorities. This editorial explores the underlying mechanisms contributing to these outcomes and discusses the clinical implications for targeted management strategies in high-risk groups. The results emphasize the need for comprehensive approaches to mitigate the heightened risks faced by recurrent stroke patients during the COVID-19 pandemic.

Subjective smell and taste dysfunctions and prognosis in patients with COVID-19 admitted to a major public hospital in Southern Brazil: A retrospective cohort study (NUTRICOVID19)

The literature notes that coronavirus disease 2019 (COVID-19) patients with olfactory disturbances tend to have lower disease severity and that olfactory disturbances may act as a protective factor against mortality. So, this study aimed to explore the association of smell and/or taste disturbance with disease severity and all-cause mortality among patients who were hospitalized with COVID-19. A retrospective cohort study (Nutrition and COVID-19 Study [NUTRICOVID19]) was conducted with 1331 patients (men and women, age ≥ 18 years) hospitalized with COVID-19 between June and December 2020. Poisson and Cox regressions were used to investigate the unadjusted and adjusted associations between smell and/or taste disturbance and the following prognostic indicators: length of stay (LOS), intensive care unit admission, need for invasive mechanical ventilation (IMV), and mortality. Patients with altered smell and/or taste had a shorter LOS (9 vs 11 days), were less likely to require IMV (22% vs 35.1%), and experienced lower mortality (17.1% vs 29.2%) compared to those without such symptoms. After multivariable adjustment, patients with smell and/or taste disturbances were 33% less likely to need IMV compared to those without such symptoms (RR = 0.67; 95% CI = 0.50-0.88), but the relationship between these symptoms and mortality lost statistical significance. In this population of patients with COVID-19, the presence of smell and/or taste disturbances was associated to lower rates of IMV.

SARS-CoV-2 induced abducens nerve palsy: A case report and response to methylprednisolone

Introduction

The abducens nerve (sixth cranial nerve) is a motor nerve that innervates the lateral rectus muscle, playing a key role in ocular abduction. Palsy of this nerve leads to convergent strabismus and diplopia. Common causes include strokes, trauma, inflammation, and infections, though in some cases, the etiology remains undetermined. With the emergence of COVID-19, neurological manifestations such as cranial neuropathies, including abducens nerve palsy, have been reported.

Case presentation

We present a case of a previously healthy 48-year-old male diagnosed with SARS-CoV-2 infection who developed abducens nerve palsy in the left eye. Following the resolution of respiratory symptoms, strabismus persisted. Treatment with methylprednisolone was initiated, resulting in partial recovery within one week and complete resolution after three months.

Conclusion

SARS-CoV-2-induced abducens nerve palsy can be reversible with conservative treatment using methylprednisolone. Early recognition and appropriate management are crucial for achieving a favorable prognosis.

Neuropsychiatric sequelae in an experimental model of post-COVID syndrome in mice

The global impact of the COVID-19 pandemic has been unprecedented, and presently, the world is facing a new challenge known as post-COVID syndrome (PCS). Current estimates suggest that more than 100 million people are grappling with PCS, encompassing several manifestations, including pulmonary, musculoskeletal, metabolic, and neuropsychiatric sequelae (cognitive and behavioral). The mechanisms underlying PCS remain unclear. The present study aimed to: (i) comprehensively characterize the acute effects of pulmonary inoculation of the betacoronavirus MHV-A59 in immunocompetent mice at clinical, cellular, and molecular levels; (ii) examine potential acute and long-term pulmonary, musculoskeletal, and neuropsychiatric sequelae induced by the betacoronavirus MHV-A59; and to (iii) assess sex-specific differences. Male and female C57Bl/6 mice were initially inoculated with varying viral titers (3x103 to 3x105 PFU/30 μL) of the betacoronavirus MHV-A59 via the intranasal route to define the highest inoculum capable of inducing disease without causing mortality. Further experiments were conducted with the 3x104 PFU inoculum. Mice exhibited an altered neutrophil/lymphocyte ratio in the blood in the 2nd and 5th day post-infection (dpi). Marked lung lesions were characterized by hyperplasia of the alveolar walls, infiltration of polymorphonuclear leukocytes (PMN) and mononuclear leukocytes, hemorrhage, increased concentrations of CCL2, CCL3, CCL5, and CXCL1 chemokines, as well as high viral titers until the 5th dpi. While these lung inflammatory signs resolved, other manifestations were observed up to the 60 dpi, including mild brain lesions with gliosis and hyperemic blood vessels, neuromuscular dysfunctions, anhedonic-like behavior, deficits in spatial working memory, and short-term aversive memory. These musculoskeletal and neuropsychiatric complications were exclusive to female mice and prevented after ovariectomy. In summary, our study describes for the first time a novel sex-dependent model of PCS focused on neuropsychiatric and musculoskeletal disorders. This model provides a unique platform for future investigations regarding the effects of acute therapeutic interventions on the long-term sequelae unleashed by betacoronavirus infection.

Neurologic manifestations of COVID-19 and viral test in cerebrospinal fluid

BACKGROUND

Neurological manifestations are present in about one-third of COVID-19 cases, ranging from mild symptoms, such as anosmia, to more severe forms like demyelinating syndromes. Although direct invasion of the CNS has been demonstrated, the immune- mediated pathway is also described and more accepted. Even in cases where viral detection in CSF is absent, it should not rule out neuroinvasion. There are few prospective studies about neurological manifestations of COVID-19, especially with viral tests in CSF; as well there are still many questions about COVID-19 associated with neurological disease. Thus, we describe clinical and CSF findings of a prospective cohort of patients with nasal positive tests for SARS-CoV-2 and neurological involvement. We also discuss the pathogenic mechanisms related to these manifestations.

METHODS AND FINDINGS

This is a prospective cohort study; 27 patients were evaluated according to clinical presentation, the time interval between COVID-19 diagnosis and onset of neurological alterations, syndromic diagnosis, imaging and CSF findings. Real time polymerase chain reaction for SARS-CoV-2 genome was performed in all CSF samples. 2 RT-PCR in spinal cord fluid resulted positive in 9 (33.3%) cases, five of them had a positive swab nasal test concomitant to neurologic disease. Respiratory signs were described in 12 out 27 patients, five of them with viral detection in CSF. White cell counts in CSF were normal range in the majority of cases, except for 3 occurrences: two patients had elevated CSF WBC counts and viral detection in CSF (10 and 36 cells/mm3) and one also had elevated CSF WBC count but viral detection in CSF was negative (21cells/mm3). The observed neurological signs encompassed a diverse neurologic spectrum, including seizures, paresis, gait abnormalities, headaches, alteration in consciousness and memory or cognitive impairment. Both imaging and CSF alterations exhibited non-specific characteristics. Syndromic diagnoses included stroke, dementia or cognitive impairments, Guillain-Barré Syndrome, encephalitis, encephalomyelitis, acute flaccid palsy and optical neuritis.

CONCLUSIONS

The patients in the present study had COVID-19 and neurologic involvement including a wide range of clinical manifestations. SARS-CoV-2 was detected in one-third of CSF samples, regardless of time interval between COVID-19 diagnosis and the onset of neurological signs. These conditions encompass various pathogenic pathways and the neuroinvasion potential of SARS-CoV-2 should be more studied.

Knowledge mapping of Guillain-Barré syndrome from January 2013 to October 2023: A bibliometric analysis

BACKGROUND

With the COVID-19 pandemic and the serious sequelae, foreign factor-induced Guillain-Barré syndrome (GBS) has become a research focus in autoimmune peripheral neuropathies. The study employs a bibliometric system to illustrate the research hotspots and trends in GBS based on pertinent literature from January 2013 to October 2023.

METHODS

The Web of Science Core Collection retrieved articles on GBS from January 1, 2013, to October 28, 2023. These articles were then visualized and statistically evaluated using VOSviewer, CiteSpace software, R version 4.2.1, and Microsoft Office Excel 2019.

RESULTS

A total of 4269 articles on GBS were gathered. The United States of America produced the most publications (28.55%, 1219/4269), followed by China (14.22%, 607/4269). The world's leading country was the United States of America, with the most publications, the most substantial international cooperation, and the highest centrality (0.17). Union of French Research Universities (UDICE)-French Research Universities in France was the most productive organization (189 articles). Lancet was the highest cocited journal (2428), and Professor Jacobs, Bart C., was the most prolific author (93). The most significant increases were shown for the keywords coronavirus, respiratory failure, and coronavirus disease 2019. The novel coronavirus is an emerging virus that may cause GBS, indicating a promising area of research.

CONCLUSIONS

The study on GBS was illustrated using bibliometrics, and it covers trends in international collaboration, publications, and research hotspots. These findings allow the scientific community to pinpoint the novel ideas and directions that will drive future GBS research.

Neuropsychiatric Manifestations of Long COVID-19: A Narrative Review of Clinical Aspects and Therapeutic Approaches

The COVID-19 (C-19) pandemic has highlighted the significance of understanding the long-term effects of this disease on the quality of life of those infected. Long COVID-19 (L-C19) presents as persistent symptoms that continue beyond the main illness period, usually lasting weeks to years. One of the lesser-known but significant aspects of L-C19 is its impact on neuropsychiatric manifestations, which can have a profound effect on an individual's quality of life. Research shows that L-C19 creates neuropsychiatric issues such as mental fog, emotional problems, and brain disease symptoms, along with sleep changes, extreme fatigue, severe head pain, tremors with seizures, and pain in nerves. People with cognitive problems plus fatigue and mood disorders experience great difficulty handling everyday activities, personal hygiene, and social interactions. Neuropsychiatric symptoms make people withdraw from social activity and hurt relationships, thus causing feelings of loneliness. The unpredictable state of L-C19 generates heavy psychological pressure through emotional suffering, including depression and anxiety. Neuropsychiatric changes such as cognitive impairment, fatigue, and mood swings make it hard for people to work or study effectively, which decreases their output at school or work and lowers their job contentment. The purpose of this narrative review is to summarize the clinical data present in the literature regarding the neuropsychiatric manifestations of L-C19, to identify current methods of diagnosis and treatment that lead to correct management of the condition, and to highlight the impact of these manifestations on patients' quality of life.

Analysis of 977 Long COVID Patients Reveals Prevalent Neuropathy and Association with Anti-Ganglioside Antibodies

Background

Long COVID (LC) is a novel condition that is characterized by persistent symptoms that last from months to years following a SARS-CoV-2 infection. While LC symptoms vary widely, neuropathy is one of the most prevalent symptoms and drastically affects patients' quality of life. However, the underlying pathophysiology of LC neuropathy remains poorly understood. Here, we investigated the prevalence and potential mechanisms of LC neuropathy in the largest LC neuropathy cohort to date.

Methods

We conducted an observational study of 977 adults with LC at Dell Medical School. Participants underwent clinical assessments, skin punch biopsy, and comprehensive metabolic, endocrine and immunological profiling. A subset of patients received treatment with intravenous immunoglobulin (IVIG).

Findings

Neuropathic symptoms were reported by 55% (534/977) participants, with skin biopsy confirming small fiber neuropathy in 56.5% (48/85) cases, affecting both epidermal and autonomic nerve fibers. Common risk factors for neuropathy, including metabolic and endocrine disorders, did not fully explain neuropathic symptoms. While general immunological markers (lymphocyte, T cell, and B cell count and C reactive protein were unremarkable, unexpectedly, we detected anti-ganglioside antibodies (AGAs) in 25% of patients with LC neuropathy, a comparable rate to other AGA-associated neuropathies. Longitudinal testing revealed persistent AGA positivity, and multiple elevated AGAs in a subset of patients. In a pilot treatment cohort of eight patients, IVIG treatment resulted in improvement of patient reported neuropathic symptoms.

Interpretation

Our findings reveal a high prevalence of small fiber neuropathy in LC, with evidence suggesting an autoimmune mechanism involving AGAs in one in four LC neuropathy patients. The therapeutic response to IVIG further supports an autoimmune pathophysiology, suggesting potential benefits of immunomodulation in LC neuropathy patients.

Risk of new-onset dementia following COVID-19 infection: a systematic review and meta-analysis

BACKGROUND

Emerging evidence suggests coronavirus disease 2019 (COVID-19) infection may increase the risk of developing dementia, although studies have reported conflicting findings. This meta-analysis aimed to synthesise the literature on the association between COVID-19 and the risk of new-onset dementia.

METHODS

PubMed, Embase and Web of Science were searched for cohort studies or case-control studies that investigated new-onset dementia development among adult COVID-19 survivors compared to individuals without COVID-19 infection from inception to 9 November 2023. Studies that exclusively involved populations younger than 18 years, with known dementia or lacked adequate data about the risk of dementia were excluded. Two authors independently conducted the screening of eligible studies, data extraction and risk of bias assessment. The primary outcome was new-onset dementia following COVID-19 infection. Data were pooled using random-effects models, with hazard ratios (HRs) and 95% confidence intervals (CIs) calculated.

RESULTS

A total of 15 retrospective cohort studies encompassing 26 408 378 participants were included. Pooled analysis indicated COVID-19 was associated with an increased risk of new-onset dementia (HR = 1.49, 95% CI: 1.33-1.68). This risk remained elevated when compared with non-COVID cohorts (HR = 1.65, 95% CI: 1.39-1.95), and respiratory tract infection cohorts (HR = 1.29, 95% CI: 1.12-1.49), but not influenza or sepsis cohorts. Increased dementia risk was observed in both males and females, as well as in individuals older than 65 years (HR = 1.68, 95% CI: 1.48-1.90), with the risk remaining elevated for up to 24 months.

CONCLUSION

This meta-analysis demonstrates a significant association between COVID-19 infection and increased risk of developing new-onset dementia, which underscores the need for cognitive monitoring and early intervention for COVID-19 survivors to address potential long-term neurological impacts.

Post-infectious central nervous system vasculitides in adults: an underdiagnosed and treatable disease part II. Neuroimaging of selected etiologies : Part II. Neuroimaging of selected etiologies

INTRODUCTION

As detailed in the first part of this review, post-infectious vasculitides are a wide and complex category, including several clinical, microbiological and neuroradiological patterns. In order to raise the suspicion for diagnosis, the knowledge of two different neuroradiological issues is needed, i.e. the knowledge of neuroimaging pattern of infections and the one of neuroimaging pattern of vasculitis.

AIMS

The main aim of this second part is to summarize the neuroradiological features of post-infectious vasculitides focusing on imaging of vessels and consequences of vessel involvement, continuing the discussion proposed in the first part about neuroimaging of infections. In some cases, the two neuroradiological issues are both simultaneously present in the same patient, but in other cases only the second one can be depicted due to the latency between infection and vasculitis.

FINDINGS

Beyond general features of cerebral vascular involvement in post-infectious vasculitides, some well-studied and homogenous diseases, as treponemal vasculitis, Varicella Zoster Virus (VZV) arteriopathy, neuroborreliosis, SARS-CoV2-related endotheliopathy are described in detail, being not rare and sometimes underdiagnosed. The main clinical and neuroradiological features of these conditions are deeply addressed, providing diagnostic clues and pictorial examples.

CONCLUSIONS

Although some general features are common in clinical presentation and neuroimaging of post-infectious vasculitides, there are few neuroimaging clues pointing out a specific microbial agent as causative. The main step is to raise the diagnostic suspicion in order to start the dedicated investigation pathway and treatment.

Clinical, epidemiological, and molecular characteristics of SARS-CoV-2 Infections among healthcare workers at a research center in the amazon region of BRAZIL from 2020 to 2022

The coronavirus disease-2019 (COVID-19) pandemic has affected different sectors of society, and healthcare workers have been particularly impacted. This study aimed to describe the clinical, epidemiological, and molecular characteristics of SARS-CoV-2 infections among healthcare workers in Evandro Chagas Institute, a research reference center in Brazil, from October 2020 to July 2022. 845 samples were collected from individuals who presented clinical symptoms of respiratory infection. Nasopharyngeal positive samples were submitted through genome sequencing. Clinical, epidemiological, and the SARS-CoV-2 lineages (or variants) were analyzed. SARS-CoV-2 positivity was detected in 31.8% (269/845) of samples with a higher prevalence of females (60.2%). The highest SARS-CoV-2 positivity rates were reported in March 2021 (39%), January 2022 (65%), and July 2022 (56%). On clinical symptoms, arthralgia, chills, and diarrhea were statistically significantly detected in 2020; fever, runny nose, and arthralgia in 2021; runny nose, and cough in 2022. On molecular analysis of SARS-CoV-2, 66 samples (25.3%, 66/269) were sequenced and the most prevalent lineage was the Omicron, representing 57.6%. Studies on the epidemiological and clinical characteristics of HCW are essential to propose control measures and work management since research centers play a major role in surveillance to identify and monitor infectious diseases.

Cognition in COVID-19 infected patients undergoing invasive ventilation: results from a multicenter retrospective study

A growing number of scientific contributions suggest that COVID-19 infection can lead to impairment of cognition, mainly in executive functions and memory domains, even in the absence of frank neurological pathologies.The primary objective of this retrospective study is to evaluate the frequency and type of inefficiencies in a selection of cognitive tests administered to a sample of subjects who, following infection, required invasive assisted ventilation and were admitted to rehabilitation wards for the treatment of functional impairment.Fifty-seven subjects were enrolled. The recruited patients undergone an assessment of verbal and visuospatial memory and executive functions, upon entry into the rehabilitation department, after discharge from intensive care. The following tests were administered: Rey Auditory Verbal Learning Test (AVLT) (immediate and delayed recall), Rey-Osterrieth Complex Figure Test (ROCFT) (copy and delayed recall), Stroop Color-Word Test, and Trail Making Test (TMT, A and B).Deficient scores, in beyond 25% of subjects, were found in the copy of the ROCFT (32.1% of subjects), and in the delayed recall of ROCFT (27.2%). Between 10 and 20% of patients presented an abnormal result in delayed recall of AVLT (16.07%), and Stroop Test (time, 15.6%, error, 11.5%). Less than 10% of the sample had abnormal performances on TMT (A, 3.5%, and B, 9.4%), and in AVLT immediate recall (8.9%). Correlations of the performances with age, sex, and education were also found.This paper highlights the high incidence of abnormal cognitive performances in this specific subpopulation of patients with COVID-19 infection.

Prion propensity of Betacoronaviruses including SARS-CoV-2

Prions are considered as sub-viral protein particles that have exceptional ability for multiple structural or functional conformational changes, that any might affect the regulation of viral infections. The aim of this study is to utilize two computational platforms to predict the prion-forming potential of the spike protein (S) in Betacoronavirus, including SARS-CoV-2 clades. The abovementioned computational platforms included two algorithms; the Prion Aggregation Prediction Algorithm (PAPA) and the Supervised Machine Learning Algorithm Called Prion RANKing and Classification (pRANK) have been adopted due to their high classifier performance proteome-wide when compared with other algorithms, such as PLAAC-LLR and prionW. The findings of this study imply the propensity of some Betacorona viruses, including the Wild type of SARS-CoV-2 and some variants, specifically as Gamma and Delta, to develop prion-like sequence which can act as a regulator for viral pathogenicity or as a biochemical threat.

Effects of nirmatrelvir/ritonavir (Paxlovid) on the nervous system: analysis on adverse events released by FDA

BACKGROUND

Nirmatrelvir/ritonavir, commonly known as Paxlovid, is one of the main drugs used to treat COVID-19. Neurological disorders are among the adverse drug reactions (ADRs) linked to Paxlovid, yet comprehensive data-mining studies based on real-world neurological adverse events induced by Paxlovid are lacking.

METHODS

It is an observational study, to reduce the risk of bias affected by COVID-19 disease, our study included only patients with COVID-19 disease. In this case, disproportionate analysis is performed using the Report Odds Ratio (ROR) and its 95% Confidence Interval (CI).

RESULTS

We screened and compared all medications associated with COVID-19 (N = 439) and found that 22 of these were linked to neurological adverse reactions. Paxlovid was associated with a threefold greater number of neurological adverse events compared to all other drugs combined (N = 11,792), with a strong signal value (ROR = 2.27).

CONCLUSIONS

Compared to all other COVID-19-related drugs, Paxlovid has the highest number and stronger signal value for neurologic-related adverse reactions. Clinicians should pay special attention to female patients taking Paxlovid within the first 30 days, monitoring for symptoms such as dysgeusia, ageusia, headache, and anosmia. In addition, headache and anosmia are not uncommon occurrences as mentioned in the instructions and should be noted.

Nucleocapsid Protein of SARS-CoV-2 Upregulates RANTES Expression in A172 Glioblastoma Cells

SARS-CoV-2, the pathogenic virus that induces COVID-19 disease, contains four structural proteins in its virion. The nucleocapsid (N) protein is one of the four structural proteins that play a crucial role in the assembly of viral RNA into ribonucleoprotein. In addition, the N protein contributes to viral pathogenesis. One of the functions attributed to the N protein is the triggering of cytokine release by lung epithelial cells, macrophages, and monocytes. This study addresses the cellular effects of the N protein of SARS-CoV-2 on cells of glial origin. We report the upregulation of the RANTES chemokine in A172 glioblastoma cells at both the mRNA and protein levels in response to exposure to SARS-CoV-2 nucleocapsid protein. The N protein did not have an effect on cell viability and cell migration.

A comparison of Gam-COVID-Vac vaccination and non-vaccination on neurological symptoms and immune response in post-COVID-19 syndrome

The post-COVID-19 syndrome may present with a range of neurological symptoms such as headaches, sleep disorders, and dizziness. The objective of this study was to examine the effectiveness of the Gam-COVID-Vac vaccine in mitigating the neurological symptoms of post-COVID-19 syndrome. The study involved 95 patients diagnosed with the neurological form of long COVID-19, who were divided into two groups according to their vaccination status. The immunological parameters of humoral immunity were evaluated by enzyme-linked immunosorbent assay (ELISA), while the parameters of cellular immunity were evaluated using flow cytometry. Administration of the vaccination resulted in a reduction in clinical symptoms of the neurological form of long COVID-19. Statistically significant differences (p = 0.035) were found in symptoms such as headaches, sleep disturbances, and dizziness, especially in central nervous system (CNS) disorders, between the groups that received the vaccination and those that did not. More than 90% of patients had elevated levels of Receptor Binding Domain (RBD) immunoglobulin G against the viral S-protein (>2,500 BAU/ml), indicating strong humoral immunity regardless of vaccination status. An increase in B-lymphocyte (CD3-CD19+) counts was noted in both groups, with levels significantly higher in the group that received the vaccination (p < 0.03). Analysis of T-cell profiles and NK (natural killer) cell levels showed no changes. The study suggests that administration of Gam-COVID-Vac vaccination could reduce the occurrence of CNS symptoms in individuals with post-COVID-19 syndrome. Although certain neurological symptoms may continue, immunization has a beneficial influence on their progression. The results emphasize the crucial role of an increased humoral immune response in individuals with post-COVID-19 syndrome, but do not show significant changes in T-cell immune parameters.

Identification of biomarkers in Alzheimer's disease and COVID-19 by bioinformatics combining single-cell data analysis and machine learning algorithms

BACKGROUND

Since its emergence in 2019, COVID-19 has become a global epidemic. Several studies have suggested a link between Alzheimer's disease (AD) and COVID-19. However, there is little research into the mechanisms underlying these phenomena. Therefore, we conducted this study to identify key genes in COVID-19 associated with AD, and evaluate their correlation with immune cells characteristics and metabolic pathways.

METHODS

Transcriptome analyses were used to identify common biomolecular markers of AD and COVID-19. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were performed on gene chip datasets (GSE213313, GSE5281, and GSE63060) from AD and COVID-19 patients to identify genes associated with both conditions. Gene ontology (GO) enrichment analysis identified common molecular mechanisms. The core genes were identified using machine learning. Subsequently, we evaluated the relationship between these core genes and immune cells and metabolic pathways. Finally, our findings were validated through single-cell analysis.

RESULTS

The study identified 484 common differentially expressed genes (DEGs) by taking the intersection of genes between AD and COVID-19. The black module, containing 132 genes, showed the highest association between the two diseases according to WGCNA. GO enrichment analysis revealed that these genes mainly affect inflammation, cytokines, immune-related functions, and signaling pathways related to metal ions. Additionally, a machine learning approach identified eight core genes. We identified links between these genes and immune cells and also found a association between EIF3H and oxidative phosphorylation.

CONCLUSION

This study identifies shared genes, pathways, immune alterations, and metabolic changes potentially contributing to the pathogenesis of both COVID-19 and AD.

Magnetoencephalography Reveals Neuroprotective Effects of COVID-19 Vaccination in Non-Human Primates

COVID-19, caused by the SARS-CoV-2 virus, can lead to widespread neurological complications, including cognitive deficits and neurodegenerative symptoms, even in the absence of significant structural brain abnormalities. The potential neuroprotective effects of SARS-CoV-2 vaccination remain underexplored. Here, we demonstrate the neuroprotective effects of a psoralen-inactivated SARS-CoV-2 vaccine in a non-human primate model using resting-state magnetoencephalography (MEG), a non-invasive neurophysiological recording technique with sub-millisecond temporal and submillimeter spatial resolution. MEG scans demonstrated substantial preservation of neural activity across multiple brain regions in vaccinated subjects compared to unvaccinated controls following viral challenge. This approach not only underscores the role of vaccination in mitigating severe neurological outcomes but also highlights the capability of MEG to detect subtle yet significant changes in brain function that may be overlooked by other imaging modalities. These findings advance our understanding of vaccine-induced neuroprotection and establish MEG as a powerful tool for monitoring brain function in the context of viral infections.

Alcohol Consumption Modulates the Development of Chronic Pain in COVID-19 Patients: A Network Meta-Analysis

The mechanisms underlying the onset and progression of chronic pain in COVID-19 patients have been understudied. Using network meta-analysis, we previously demonstrated that alcohol augments COVID-19 symptoms and pathologies possibly by inducing a severe cytokine storm. We and others have also reported that acute alcohol consumption produces analgesic effects, while chronic alcohol consumption results in hyperalgesia and chronic pain. This study aimed to identify the influence of alcohol consumption and COVID-19 on pain. Using publicly available curated gene expression data sets of differentially expressed genes (DEGs) in the prefrontal cortex (PFC) and amygdala of COVID-19 patients, we employed a bioinformatics application, QIAGEN ingenuity pathway analysis (IPA), to identify the key signaling pathways, upstream regulators, and biological functions in these brain areas known to play a role in pain. Canonical pathway analysis revealed activation of the neuropathic pain pathway and signaling pathways involving the cytokine storm, S100 family, IL-6, and neuroinflammation. IPA's network builder was employed to construct a network map of shared molecules between alcohol and pain-related constructs (discomfort, neuropathic pain, and inflammatory pain). The simulation of alcohol consumption inhibited pain in this network map. To study the influence of COVID-19, we overlaid the DEGs from the PFC and amygdala onto these networks, mimicking alcohol consumption during SARS-CoV-2 infection. Upregulation of molecules in the amygdala and PFC predicted an increase in neuropathic pain, as well as an increase in inflammatory pain in the PFC. Our results suggest that while alcohol consumption directly inhibits pain, the presence of COVID-19 exaggerates impaired cytokine signaling, neuroinflammation, and neuropathic pain signaling in the CNS providing novel insights into the signaling pathways associated with chronic pain of the COVID-19 patients.

Differences in functional outcome of COVID-19 and non-COVID-19 patients with critical illness polyneuropathy/ myopathy: a multicenter cohort study

BACKGROUND

Up to 80% of intensive care unit (ICU) patients suffer from neuromuscular disorders like critical illness polyneuropathy/myopathy (CIP/CIM), requiring further rehabilitation.

OBJECTIVE

This study investigates differences in the clinical course between Coronavirus Disease 2019 (COVID-19) and non-COVID-19 patients with CIP/CIM undergoing post-acute neurological rehabilitation (PANR) and the impact of COVID-19 on rehabilitation outcomes.

METHODS

A multicenter observational study was conducted in nine German PANR facilities. The clinical course and outcome were compared between COVID-19 and non-COVID-19 patients at rehabilitation admission and discharge. Functional outcomes were measured with the modified Ranking Scale (mRS) and the Barthel Index (BI). Functional independence was defined as either mRS Score < 3 or BI > 75 at discharge, discharged home without nursing support with a BI > 65, or discharged to further rehabilitation (phase D). To analyze outcome predictors, Cox regression was used.

RESULTS

A total of 323 patients (COVID-19 n = 166) after an ICU stay were enrolled, and outcome measures were available for 298. 56 of them achieved functional independence at discharge. COVID-19 patients had better functional scores at admission and discharge and a shorter length of stay as the non-COVID group. Pre-existing diabetes was significantly negatively associated with functioning at discharge.

CONCLUSIONS

This analysis provides the first evidence for differences and predictors of the clinical course and outcome for COVID-19 and non-COVID-19 patients with CIP/CIM in the phase of post-acute rehabilitation. Our results offer valuable impulses for rehabilitation strategies for these patients. https://drks.de/search/de , German Clinical Trials Register, ID DRKS00022845, registered on September 1, 2020.

Multicentre case-control study on the association between COVID-19 vaccines and neurological disorders (COVIVAX)

The COVIVAX study assessed the association between COVID-19 vaccination and the risk of common neurological disorders in a multicenter case-control design. Vaccination exposure was compared between individuals with a first diagnosis of a neurological disorder (cases) and age- and sex-matched controls. A total of 624 participants were enrolled, and after random 1:1 matching 265 cases and 265 matched controls (total 530 participants) were included in the analyses. The most frequent neurological diagnosis in cases were stroke (60.4%), multiple sclerosis (11.3%) and seizures (6.4%). The proportion of vaccinated participants was 72.1% among cases and 79.6% among controls. A protective role of vaccination on the risk of developing a new neurological disorder was detected in the unadjusted analysis (OR 0.50; 95% CI 0.29-0.86; p = 0.0114). After adjustment for confounders, the number of vaccination doses received was associated with a reduced risk of developing new neurological disorders for participants aged over 60 years ( p = 0.0472; OR 0.14, 95% CI 0.03-0.68), with pre-existing comorbidities (p = 0.0122; OR 0.04, 95% CI 0.01-0.99) and for stroke (p = 0.0232; OR 0.04, 95% CI 0.02-0.97). The COVIVAX study provided no warning sign regarding an increase in the risk of developing new neurological disorders following COVID-19 vaccination of any type or doses. A potentially protective effect of multiple doses of COVID-19 vaccines against the risk of stroke in people aged over 60 needs to be confirmed by further studies.

SARS-CoV-2: A synergy to the Alzheimer's disease

COVID-19 was a nightmare in humankind's history that challenged our advanced medical technology. All credit goes to the researchers who played a crucial role in curbing COVID-19 and proved our medical technology supremacy. However, COVID-19 has left some mysterious scars on human well-being. It is believed that COVID-19 has a significant negative impact on various cardiovascular (CVS) and central nervous system (CNS) diseases, especially in the case of CNS diseases like Alzheimer's. Surprisingly, COVID-19 affects the respiratory system, whereas Alzheimer's disease (AD) alters brain function. To explain this phenomenon, several hypotheses were proposed, but the mechanism needs to be clearly understood. Another critical thing to be concerned about is that COVID-19 will worsen pre-existing conditions and lead to the onset of AD. In the race to curb COVID-19, the invention of vaccines was speeded up, and it is necessary to fight against COVID-19. However, postvaccination follow-up is mandatory when an individual is a victim of AD. In this review article, we compiled the various dreadful effects of the COVID-19 virus on AD, the Post effects of the virus on AD, and the effect of the COVID-19 vaccination on AD. This article provides a new direction for research concerning COVID-19 and AD.