Persistent neurologic symptoms and cognitive dysfunction in non-hospitalized Covid-19 "long haulers"

Post-acute sequelae of covid-19 six to 12 months after infection: population based study

OBJECTIVES

To describe symptoms and symptom clusters of post-covid syndrome six to 12 months after acute infection, describe risk factors, and examine the association of symptom clusters with general health and working capacity.

DESIGN

Population based, cross sectional study SETTING: Adults aged 18-65 years with confirmed SARS-CoV-2 infection between October 2020 and March 2021 notified to health authorities in four geographically defined regions in southern Germany.

PARTICIPANTS

50 457 patients were invited to participate in the study, of whom 12 053 (24%) responded and 11 710 (58.8% (n=6881) female; mean age 44.1 years; 3.6% (412/11 602) previously admitted with covid-19; mean follow-up time 8.5 months) could be included in the analyses.

MAIN OUTCOME MEASURES

Symptom frequencies (six to 12 months after versus before acute infection), symptom severity and clustering, risk factors, and associations with general health recovery and working capacity.

RESULTS

The symptom clusters fatigue (37.2% (4213/11 312), 95% confidence interval 36.4% to 38.1%) and neurocognitive impairment (31.3% (3561/11 361), 30.5% to 32.2%) contributed most to reduced health recovery and working capacity, but chest symptoms, anxiety/depression, headache/dizziness, and pain syndromes were also prevalent and relevant for working capacity, with some differences according to sex and age. Considering new symptoms with at least moderate impairment of daily life and ≤80% recovered general health or working capacity, the overall estimate for post-covid syndrome was 28.5% (3289/11 536, 27.7% to 29.3%) among participants or at least 6.5% (3289/50 457) in the infected adult population (assuming that all non-responders had completely recovered). The true value is likely to be between these estimates.

CONCLUSIONS

Despite the limitation of a low response rate and possible selection and recall biases, this study suggests a considerable burden of self-reported post-acute symptom clusters and possible sequelae, notably fatigue and neurocognitive impairment, six to 12 months after acute SARS-CoV-2 infection, even among young and middle aged adults after mild infection, with a substantial impact on general health and working capacity.

TRIAL REGISTRATION

German registry of clinical studies DRKS 00027012.

Genetics of COVID-19 and myalgic encephalomyelitis/chronic fatigue syndrome: a systematic review

COVID‐19 and ME/CFS present with some similar symptoms, especially physical and mental fatigue. In order to understand the basis of these similarities and the possibility of underlying common genetic components, we performed a systematic review of all published genetic association and cohort studies regarding COVID‐19 and ME/CFS and extracted the genes along with the genetic variants investigated. We then performed gene ontology and pathway analysis of those genes that gave significant results in the individual studies to yield functional annotations of the studied genes using protein analysis through evolutionary relationships (PANTHER) VERSION 17.0 software. Finally, we identified the common genetic components of these two conditions. Seventy‐one studies for COVID‐19 and 26 studies for ME/CFS were included in the systematic review in which the expression of 97 genes for COVID‐19 and 429 genes for ME/CFS were significantly affected. We found that ACE, HLA‐A, HLA‐C, HLA‐DQA1, HLA‐DRB1, and TYK2 are the common genes that gave significant results. The findings of the pathway analysis highlight the contribution of inflammation mediated by chemokine and cytokine signaling pathways, and the T cell activation and Toll receptor signaling pathways. Protein class analysis revealed the contribution of defense/immunity proteins, as well as protein‐modifying enzymes. Our results suggest that the pathogenesis of both syndromes could involve some immune dysfunction.

Glial functions in the blood-brain communication at the circumventricular organs

The circumventricular organs (CVOs) are located around the brain ventricles, lack a blood-brain barrier (BBB) and sense blood-derived molecules. This review discusses recent advances in the importance of CVO functions, especially glial cells transferring periphery inflammation signals to the brain. The CVOs show size-limited vascular permeability, allowing the passage of molecules with molecular weight <10,000. This indicates that the lack of an endothelial cell barrier does not mean the free movement of blood-derived molecules into the CVO parenchyma. Astrocytes and tanycytes constitute a dense barrier at the distal CVO subdivision, preventing the free diffusion of blood-derived molecules into neighboring brain regions. Tanycytes in the CVOs mediate communication between cerebrospinal fluid and brain parenchyma via transcytosis. Microglia and macrophages of the CVOs are essential for transmitting peripheral information to other brain regions via toll-like receptor 2 (TLR2). Inhibition of TLR2 signaling or depletion of microglia and macrophages in the brain eliminates TLR2-dependent inflammatory responses. In contrast to TLR2, astrocytes and tanycytes in the CVOs of the brain are crucial for initiating lipopolysaccharide (LPS)-induced inflammatory responses via TLR4. Depletion of microglia and macrophages augments LPS-induced fever and chronic sickness responses. Microglia and macrophages in the CVOs are continuously activated, even under normal physiological conditions, as they exhibit activated morphology and express the M1/M2 marker proteins. Moreover, the microglial proliferation occurs in various regions, such as the hypothalamus, medulla oblongata, and telencephalon, with a marked increase in the CVOs, due to low-dose LPS administration, and after high-dose LPS administration, proliferation is seen in most brain regions, except for the cerebral cortex and hippocampus. A transient increase in the microglial population is beneficial during LPS-induced inflammation for attenuating sickness response. Transient receptor potential receptor vanilloid 1 expressed in astrocytes and tanycytes of the CVOs is responsible for thermoregulation upon exposure to a warm environment less than 37°C. Alternatively, Nax expressed in astrocytes and tanycytes of the CVOs is crucial for maintaining body fluid homeostasis. Thus, recent findings indicate that glial cells in the brain CVOs are essential for initiating neuroinflammatory responses and maintaining body fluid and thermal homeostasis.

Brain Fog and Quality of Life at Work in Non-Hospitalized Patients after COVID-19

Background: There is still a need for studies on the quality of life (QoL) at work among COVID-19 survivors. Therefore, we aimed to evaluate the association between the brain fog symptoms and the QoL at work in non-hospitalized patients with previous SARS-CoV-2 infection. Methods: Three hundred non-hospitalized patients (79.33% women; median age, 36 years; interquartile range, 30-48 years) were included in the final analysis. An anonymous neuropsychological questionnaire containing eight different questions on the presence of brain fog symptoms in four time intervals, i.e., pre-COVID-19 and 0-4, 4-12, and >12 weeks after infection, was retrospectively introduced to patients and staff of the University Hospital in Krakow. Additionally, a four-point Likert scale was used to evaluate QoL at work in four time periods. Included were participants aged ≥ 18 years in whom the diagnosis of COVID-19 was confirmed by the RT-PCR from nasopharyngeal swab and the first symptoms occurred no earlier than 3 months before the completion of the questionnaire. Results: Before SARS-CoV-2 infection, 28.00% (n = 84) of patients reported poor QoL at work. Within 4, 4-12, and >12 weeks after infection, a decrease in QoL was observed in 75.67% (n = 227), 65.00% (n = 195), and 53.66% (n = 161) of patients, respectively (p < 0.001). With increasing deterioration of the QoL at work, the number of brain fog symptoms increased, and patients with severe QoL impairment exhibited a median of five symptoms for <4, 4-12, and >12 weeks post-COVID-19. In the multivariable logistic regression model, predictors of the deterioration of the QoL at work depended on the time from COVID-19 onset; in the acute phase of the disease (<4 weeks), it was predicted by impairment in remembering information from the past (OR 1.88, 95%CI: 1.18-3.00, p = 0.008) and multitasking (OR 1.96, 95%CI: 1.48-2.58, p < 0.001). Furthermore, an impairment in the QoL at work 4-12 weeks and >12 weeks after COVID-19 was independently associated with age (OR 0.46, 95%CI: 0.25-0.85, p = 0.014 and OR 1.03, 95%CI: 1.01-1.05, p = 0.025, respectively), problems with multitasking (OR 2.05, 95%CI: 1.40-3.01, p < 0.001 and OR 1.75, 95%CI: 1.15-2.66, p = 0.009, respectively), answering questions in an understandable/unambiguous manner (OR 1.99, 95%CI: 1.27-3.14, p = 0.003 and OR 2.00, 95%CI: 1.47-2.36, p = 0.001, respectively), and, only for the >12 week interval, problems with remembering information from the past (OR 2.21, 95%CI: 1.24-3.92, p = 0.007). Conclusions: Certain brain fog symptoms, such as impaired memory or multitasking, are predictors of a poorer QoL at work not only during the acute phase of COVID-19 but also within more than 12 weeks after the onset of infection.

Headaches and Dizziness as Disabling, Persistent Symptoms in Patients with Long COVID-A National Multicentre Study

Background: Currently, about 15% of coronavirus disease-19 (COVID-19) patients are affected by Long COVID worldwide; however, this condition has not yet been sufficiently studied. The aim of this study was to identify the impact of symptom persistence as well as clinical and socio-demographic variables in a cohort of people with Long COVID. Methods: We conducted a descriptive cross-sectional study of a sample of adult patients from different Spanish regions presenting with Long COVID. Data collection was conducted between April and July 2021. Functional status and dependency were assessed. Results: A multivariate linear regression was performed, and the model was statistically significant (F (7; 114) = 8.79; p < 0.001), according to the overall ALDQ score. The variables with a statistically significant effect on the degree of dependence were age (p = 0.014), time since diagnosis (p = 0.02), headaches (p = 0.031), and dizziness (p = 0.039). Functional status post-COVID showed a positive and significant relationship with the percentage of dependence (p < 0.001). Conclusions: People affected by Long COVID showed moderate dependency status and limitations in functionality. Those with neurological symptoms, such as dizziness and headaches, as well as older age, showed a higher degree of dependency. Improvements in dependency status occurred with increasing time since diagnosis.

Cognitive dysfunction associated with COVID-19: Prognostic role of circulating biomarkers and microRNAs

COVID-19 is renowned as a multi-organ disease having subacute and long-term effects with a broad spectrum of clinical manifestations. The evolving scientific and clinical evidence demonstrates that the frequency of cognitive impairment after COVID-19 is high and it is crucial to explore more clinical research and implement proper diagnostic and treatment strategies. Several central nervous system complications have been reported as comorbidities of COVID-19. The changes in cognitive function associated with neurodegenerative diseases develop slowly over time and are only diagnosed at an already advanced stage of molecular pathology. Hence, understanding the common links between COVID-19 and neurodegenerative diseases will broaden our knowledge and help in strategizing prognostic and therapeutic approaches. The present review focuses on the diverse neurodegenerative changes associated with COVID-19 and will highlight the importance of major circulating biomarkers and microRNAs (miRNAs) associated with the disease progression and severity. The literature analysis showed that major proteins associated with central nervous system function, such as Glial fibrillary acidic protein, neurofilament light chain, p-tau 181, Ubiquitin C-terminal hydrolase L1, S100 calcium-binding protein B, Neuron-specific enolase and various inflammatory cytokines, were significantly altered in COVID-19 patients. Furthermore, among various miRNAs that are having pivotal roles in various neurodegenerative diseases, miR-146a, miR-155, Let-7b, miR-31, miR-16 and miR-21 have shown significant dysregulation in COVID-19 patients. Thus the review consolidates the important findings from the numerous studies to unravel the underlying mechanism of neurological sequelae in COVID-19 and the possible association of circulatory biomarkers, which may serve as prognostic predictors and therapeutic targets in future research.

Neuropsychiatric sequelae of long COVID-19: Pilot results from the COVID-19 neurological and molecular prospective cohort study in Georgia, USA

Background

As the coronavirus disease 2019 (COVID-19) pandemic continues, there has been a growing interest in the chronic sequelae of COVID-19. Neuropsychiatric symptoms are observed in the acute phase of infection, but there is a need for accurate characterization of how these symptoms evolve over time. Additionally, African American populations have been disproportionately affected by the COVID-19 pandemic. The COVID-19 Neurological and Molecular Prospective Cohort Study in Georgia (CONGA) was established to investigate the severity and chronicity of these neurologic findings over the five-year period following infection.

Methods

The CONGA study aims to recruit COVID-19 positive adult patients in Georgia, United States from both the inpatient and outpatient setting, with 50% being African American. This paper reports our preliminary results from the baseline visits of the first 200 patients recruited who were on average 125 days since having a positive COVID-19 test. The demographics, self-reported symptoms, comorbidities, and quantitative measures of depression, anxiety, smell, taste, and cognition were analyzed. Cognitive measures were compared to demographically matched controls. Blood and mononuclear cells were drawn and stored for future analysis.

Results

Fatigue was the most reported symptom in the study cohort (68.5%). Thirty percent of participants demonstrated hyposmia and 30% of participants demonstrated hypogeusia. Self-reported neurologic dysfunction did not correlate with dysfunction on quantitative neurologic testing. Additionally, self-reported symptoms and comorbidities were associated with depression and anxiety. The study cohort performed worse on cognitive measures compared to demographically matched controls, and African American patients scored lower compared to non-Hispanic White patients on all quantitative cognitive testing.

Conclusion

Our results support the growing evidence that there are chronic neuropsychiatric symptoms following COVID-19 infection. Our results suggest that self-reported neurologic symptoms do not appear to correlate with associated quantitative dysfunction, emphasizing the importance of quantitative measurements in the complete assessment of deficits. Self-reported symptoms are associated with depression and anxiety. COVID-19 infection appears to be associated with worse performance on cognitive measures, though the disparity in score between African American patients and non-Hispanic White patients is likely largely due to psychosocial, physical health, and socioeconomic factors.

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Neuropsychiatric symptoms are often reported following COVID-19 infection.

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Self-reported symptoms may not be associated with objective dysfunction.

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Self-reported symptoms may be associated with depression and anxiety.

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Cognitive testing may overestimate clinical impairment in disadvantaged populations.

Post-acute sequelae of COVID-19 symptom phenotypes and therapeutic strategies: A prospective, observational study

BACKGROUND

Post-acute sequelae of COVID-19 (PASC) includes a heterogeneous group of patients with variable symptomatology, who may respond to different therapeutic interventions. Identifying phenotypes of PASC and therapeutic strategies for different subgroups would be a major step forward in management.

METHODS

In a prospective cohort study of patients hospitalized with COVID-19, 12-month symptoms and quantitative outcome metrics were collected. Unsupervised hierarchical cluster analyses were performed to identify patients with: (1) similar symptoms lasting ≥4 weeks after acute SARS-CoV-2 infection, and (2) similar therapeutic interventions. Logistic regression analyses were used to evaluate the association of these symptom and therapy clusters with quantitative 12-month outcome metrics (modified Rankin Scale, Barthel Index, NIH NeuroQoL).

RESULTS

Among 242 patients, 122 (50%) reported ≥1 PASC symptom (median 3, IQR 1-5) lasting a median of 12-months (range 1-15) post-COVID diagnosis. Cluster analysis generated three symptom groups: Cluster1 had few symptoms (most commonly headache); Cluster2 had many symptoms including high levels of anxiety and depression; and Cluster3 primarily included shortness of breath, headache and cognitive symptoms. Cluster1 received few therapeutic interventions (OR 2.6, 95% CI 1.1-5.9), Cluster2 received several interventions, including antidepressants, anti-anxiety medications and psychological therapy (OR 15.7, 95% CI 4.1-59.7) and Cluster3 primarily received physical and occupational therapy (OR 3.1, 95%CI 1.3-7.1). The most severely affected patients (Symptom Cluster 2) had higher rates of disability (worse modified Rankin scores), worse NeuroQoL measures of anxiety, depression, fatigue and sleep disorder, and a higher number of stressors (all P<0.05). 100% of those who received a treatment strategy that included psychiatric therapies reported symptom improvement, compared to 97% who received primarily physical/occupational therapy, and 83% who received few interventions (P = 0.042).

CONCLUSIONS

We identified three clinically relevant PASC symptom-based phenotypes, which received different therapeutic interventions with varying response rates. These data may be helpful in tailoring individual treatment programs.

Neuropsychiatric phenotype of post COVID-19 syndrome in non-hospitalized patients

The post COVID-19 syndrome (PCS) is an emerging phenomenon worldwide with enormous socioeconomic impact. While many patients describe neuropsychiatric deficits, the symptoms are yet to be assessed and defined systematically. In this prospective cohort study, we report on the results of a neuropsychiatric consultation implemented in May 2021. A cohort of 105 consecutive patients with merely mild acute course of disease was identified by its high symptom load 6 months post infection using a standardized neurocognitive and psychiatric-psychosomatic assessment. In this cohort, we found a strong correlation between higher scores in questionnaires for fatigue (MFI-20), somatization (PHQ15) and depression (PHQ9) and worse functional outcome as measured by the post COVID functional scale (PCFS). In contrast, neurocognitive scales correlated with age, but not with PCFS. Standard laboratory and cardiopulmonary biomarkers did not differ between the group of patients with predominant neuropsychiatric symptoms and a control group of neuropsychiatrically unaffected PCS patients. Our study delineates a phenotype of PCS dominated by symptoms of fatigue, somatisation and depression. The strong association of psychiatric and psychosomatic symptoms with the PCFS warrants a systematic evaluation of psychosocial side effects of the pandemic itself and psychiatric comorbidities on the long-term outcome of patients with SARS-CoV-2 infection.

Post-COVID syndrome? COVID-19 survivors suffer from cognitive difficulties, somatic complaints and anxiety

Aim: Although primarily known as a respiratory system pathology, COVID-19 may cause various systems and cause serious complications including neuropsychiatric problems. These complications may be formulized as post-COVID syndrome. The current study aims to investigate prolonged cognitive, somatic and psychiatric effects of COVID-19. Material and Method: A total number of 120 COVID-19 survivors were compared with 120 health controls in means of three measures, which are Cognitive Failures Questionnaire (CFQ), Body Sensations Questionnaire (BSQ), Hospital Anxiety and Depression Scale (HADS) to assess cognitive difficulties, body perceptions and anxiety/depression. Results: Our findings show that COVID-19 survivors have reported significantly more cognitive difficulties, increased body sensations and higher levels of anxiety. The groups did not differ in means of depression scores. Further, the measures were significantly correlated with each other. Conclusion: This study reveal that COVID-19 survivors suffer from significant cognitive deficits in everyday activities, are significantly more sensitive to various body sensations and have increased anxiety levels. In discordance with the current literature, our findings showed that COVID-19 patients are not more depressed than healthy subjects. In summary, the current study showed that various neuropsychiatric complications may be an important part of prolonged effects of COVID-19.

Role of Demyelination in the Persistence of Neurological and Mental Impairments after COVID-19

Long-term neurological and mental complications of COVID-19, the so-called post-COVID syndrome or long COVID, affect the quality of life. The most persistent manifestations of long COVID include fatigue, anosmia/hyposmia, insomnia, depression/anxiety, and memory/attention deficits. The physiological basis of neurological and psychiatric disorders is still poorly understood. This review summarizes the current knowledge of neurological sequelae in post-COVID patients and discusses brain demyelination as a possible mechanism of these complications with a focus on neuroimaging findings. Numerous reviews, experimental and theoretical studies consider brain demyelination as one of the mechanisms of the central neural system impairment. Several factors might cause demyelination, such as inflammation, direct effect of the virus on oligodendrocytes, and cerebrovascular disorders, inducing myelin damage. There is a contradiction between the solid fundamental basis underlying demyelination as the mechanism of the neurological injuries and relatively little published clinical evidence related to demyelination in COVID-19 patients. The reason for this probably lies in the fact that most clinical studies used conventional MRI techniques, which can detect only large, clearly visible demyelinating lesions. A very limited number of studies use specific methods for myelin quantification detected changes in the white matter tracts 3 and 10 months after the acute phase of COVID-19. Future research applying quantitative MRI assessment of myelin in combination with neurological and psychological studies will help in understanding the mechanisms of post-COVID complications associated with demyelination.

Long-COVID and long-term cancer survivorship-Shared lessons and opportunities

As of 2022, close to 90 million persons in the United States, 243 million persons in Europe and 585 million worldwide have been infected with the novel SARS‐CoV‐2 (COVID‐19) virus and survived. Estimates vary but suggest that up to 50% may experience long‐term sequelae, termed ‘Long‐COVID’. While Long‐COVID is a new condition, the phenomenon of disabling long‐term effects following an illness requiring ongoing surveillance and management is not. In this commentary, we discuss how Long‐COVID parallels the experiences of long‐term cancer survivors, highlight shared challenges and offer opportunities to improve research and clinical care for both growing populations of patients as well as other long‐term chronic, disabling conditions.

Case report: Treatment of long COVID with a SARS-CoV-2 antiviral and IL-6 blockade in a patient with rheumatoid arthritis and SARS-CoV-2 antigen persistence

Introduction

Long COVID, or post-acute sequelae of SARS-CoV-2 infection (PASC) in ∼30% of all infected individuals. Here, we present a case of PASC in a patient with rheumatoid arthritis characterized by viral persistence in the nasopharynx for 6 months after acute infection. We demonstrate transient disappearance of antigen persistence and decreased antiviral and autoimmune T cell responses after nirmatrelvir/ritonavir and tocilizumab treatment.

Case presentation

A 37-year-old female with a 7-year history of rheumatoid arthritis enrolled in a COVID-19 research study was found to continuously test SARS-CoV-2 antigen positive in the nasopharynx for 6 months after acute infection. She simultaneously presented with new-onset PASC symptoms including chronic occipital headache and periods of intense fatigue 8 weeks after acute infection. The patient was prescribed nirmatrelvir/ritonavir to treat SARS-CoV-2 persistence at 3.5 months post-acute infection and observed a reduction in PASC symptoms 3 weeks after completing antiviral treatment. After resurgence of PASC symptoms, she stopped treatment with tocilizumab for rheumatoid arthritis to attempt complete SARS-CoV-2 viral clearance. The severity of the patient's PASC symptoms subsequently increased, and she developed new-onset brain fog in addition to previous symptoms, which resolved after resumption of tocilizumab treatment. Assessment of adaptive immune responses demonstrated that nirmatrelvir/ritonavir and tocilizumab treatment decreased antiviral and autoreactive T cell activation. After resuming tocilizumab treatment, the patient's PASC symptoms were significantly reduced, but nasopharyngeal antigen positivity remained.

Conclusion

These data suggest that nirmatrelvir/ritonavir should be considered in the treatment of PASC in patients who have SARS-CoV-2 antigen persistence, though care must be taken to monitor the patient for symptom resurgence or viral reactivation. In addition, the IL-6 inhibitor tocilizumab may ameliorate PASC symptoms in patients with persistent headache, fatigue, and brain fog.

A New Look on Long-COVID Effects: The Functional Brain Fog Syndrome

Epidemiological data and etiopathogenesis of brain fog are very heterogeneous in the literature, preventing adequate diagnosis and treatment. Our study aimed to explore the relationship between brain fog, neuropsychiatric and cognitive symptoms in the general population. A sample of 441 subjects underwent a web-based survey, including the PANAS, the DASS-21, the IES-R, the Beck Cognitive Insight Scale, and a questionnaire investigating demographic information, brain fog, subjective cognitive impairments (Scc) and sleep disorders. ANOVA, ANCOVA, correlation and multiple stepwise regression analyses were performed. In our sample, 33% of participants were defined as Healthy Subjects (HS; no brain fog, no Scc), 27% as Probable Brain Fog (PBF; brain fog or Scc), and 40% as Functional Brain Fog (FBF; brain fog plus Scc). PBF and FBF showed higher levels of neuropsychiatric symptoms than HS, and FBF showed the worst psychological outcome. Moreover, worse cognitive symptoms were related to the female gender, greater neuropsychiatric symptoms, sleep disorders, and rumination/indecision. Being a woman and more severe neuropsychiatric symptoms were predictors of FBF severity. Our data pointed out a high prevalence and various levels of severity and impairments of brain fog, suggesting a classificatory proposal and a multifaceted etiopathogenic model, thus facilitating adequate diagnostic and therapeutic approaches.

Pharmacological Potential of Flavonoids against Neurotropic Viruses

Flavonoids are a group of natural compounds that have been described in the literature as having anti-inflammatory, antioxidant, and neuroprotective compounds. Although they are considered versatile molecules, little has been discussed about their antiviral activities for neurotropic viruses. Hence, the present study aimed to investigate the pharmacological potential of flavonoids in the face of viruses that can affect the central nervous system (CNS). We carried out research from 2011 to 2021 using the Pubmed platform. The following were excluded: articles not in the English language, letters to editors, review articles and papers that did not include any experimental or clinical tests, and papers that showed antiviral activities against viruses that do not infect human beings. The inclusion criteria were in silico predictions and preclinical pharmacological studies, in vitro, in vivo and ex vivo, and clinical studies with flavonoids, flavonoid fractions and extracts that were active against neurotropic viruses. The search resulted in 205 articles that were sorted per virus type and discussed, considering the most cited antiviral activities. Our investigation shows the latest relevant data about flavonoids that have presented a wide range of actions against viruses that affect the CNS, mainly influenza, hepatitis C and others, such as the coronavirus, enterovirus, and arbovirus. Considering that these molecules present well-known anti-inflammatory and neuroprotective activities, using flavonoids that have demonstrated both neuroprotective and antiviral effects could be viewed as an alternative for therapy in the course of CNS infections.

New-onset and persistent neurological and psychiatric sequelae of COVID-19 compared to influenza: A retrospective cohort study in a large New York City healthcare network

OBJECTIVES

Neurological and neuropsychiatric manifestations of post-acute SARS-CoV-2 infection (neuro-PASC) are common among COVID-19 survivors, but it is unknown how neuro-PASC differs from influenza-related neuro-sequelae. This study investigated the clinical characteristics of COVID-19 patients with and without new-onset neuro-PASC, and of flu patients with similar symptoms.

METHODS

We retrospectively screened 18,811 COVID-19 patients and 5772 flu patients between January 2020 and June 2021 for the presence of new-onset neuro-sequelae that persisted at least 2 weeks past the date of COVID-19 or flu diagnosis.

RESULTS

We observed 388 COVID-19 patients with neuro-PASC versus 149 flu patients with neuro-sequelae. Common neuro-PASC symptoms were anxiety (30%), depression (27%), dizziness (22%), altered mental status (17%), chronic headaches (17%), and nausea (11%). The average time to neuro-PASC onset was 138 days, with hospitalized patients reporting earlier onset than non-hospitalized patients. Neuro-PASC was associated with female sex and older age (p < 0.05), but not race, ethnicity, most comorbidities, or COVID-19 disease severity (p > 0.05). Compared to flu patients, COVID-19 patients were older, exhibited higher incidence of altered mental status, developed symptoms more quickly, and were prescribed psychiatric drugs more often (p < 0.05).

CONCLUSIONS

This study provides additional insights into neuro-PASC risk factors and differentiates between post-COVID-19 and post-flu neuro-sequelae.

SARS-CoV-2 and the central nervous system: Emerging insights into hemorrhage-associated neurological consequences and therapeutic considerations

Coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) continues to impact our lives by causing widespread illness and death and poses a threat due to the possibility of emerging strains. SARS-CoV-2 targets angiotensin-converting enzyme 2 (ACE2) before entering vital organs of the body, including the brain. Studies have shown systemic inflammation, cellular senescence, and viral toxicity-mediated multi-organ failure occur during infectious periods. However, prognostic investigations suggest that both acute and long-term neurological complications, including predisposition to irreversible neurodegenerative diseases, can be a serious concern for COVID-19 survivors, especially the elderly population. As emerging studies reveal sites of SARS-CoV-2 infection in different parts of the brain, potential causes of chronic lesions including cerebral and deep-brain microbleeds and the likelihood of developing stroke-like pathologies increases, with critical long-term consequences, particularly for individuals with neuropathological and/or age-associated comorbid conditions. Our recent studies linking the blood degradation products to genome instability, leading to cellular senescence and ferroptosis, raise the possibility of similar neurovascular events as a result of SARS-CoV-2 infection. In this review, we discuss the neuropathological consequences of SARS-CoV-2 infection in COVID survivors, focusing on possible hemorrhagic damage in brain cells, its association to aging, and the future directions in developing mechanism-guided therapeutic strategies.

Therapeutic Approaches to the Neurologic Manifestations of COVID-19

As of May 2022, there have been more than 527 million infections with severe acute respiratory disease coronavirus type 2 (SARS-CoV-2) and over 6.2 million deaths from Coronavirus Disease 2019 (COVID-19) worldwide. COVID-19 is a multisystem illness with important neurologic consequences that impact long-term morbidity and mortality. In the acutely ill, the neurologic manifestations of COVID-19 can include distressing but relatively benign symptoms such as headache, myalgias, and anosmia; however, entities such as encephalopathy, stroke, seizures, encephalitis, and Guillain-Barre Syndrome can cause neurologic injury and resulting disability that persists long after the acute pulmonary illness. Furthermore, as many as one-third of patients may experience persistent neurologic symptoms as part of a Post-Acute Sequelae of SARS-CoV-2 infection (Neuro-PASC) syndrome. This Neuro-PASC syndrome can affect patients who required hospitalization for COVID-19 or patients who did not require hospitalization and who may have had minor or no pulmonary symptoms. Given the large number of individuals affected and the ability of neurologic complications to impair quality of life and productivity, the neurologic manifestations of COVID-19 are likely to have major and long-lasting personal, public health, and economic consequences. While knowledge of disease mechanisms and therapies acquired prior to the pandemic can inform us on how to manage patients with the neurologic manifestations of COVID-19, there is a critical need for improved understanding of specific COVID-19 disease mechanisms and development of therapies that target the neurologic morbidities of COVID-19. This current perspective reviews evidence for proposed disease mechanisms as they inform the neurologic management of COVID-19 in adult patients while also identifying areas in need of further research.

The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

EEG background frequency is associated with discharge outcomes in non-ICU hospitalized patients with COVID-19

Objective

To assess risk factors for encephalopathy in non-ICU hospitalized patients with COVID-19 and the effect of encephalopathy on short-term outcomes.

Methods

We collected clinical and electrophysiological characteristics of fifty patients with COVID-19 infection admitted to a ward service and who had an electroencephalogram (EEG) performed. Associations with short-term outcomes including hospital length of stay and discharge disposition were determined from univariate and multivariate statistical analysis.

Results

Clinical delirium was associated with encephalopathy on EEG, cefepime use was associated with increased length of stay, and of all factors analyzed, background frequency on EEG alone was correlated with discharge disposition.

Conclusion

Encephalopathy is one of the major determinants of short-term outcomes in hospitalized non-ICU patients with COVID-19.

Cognitive function in non-hospitalized patients 8–13 months after acute COVID-19 infection: A cohort study in Norway

Studies have reported reduced cognitive function following COVID-19 illness, mostly from hospital settings with short follow-up times. This study recruited non-hospitalized COVID-19 patients from a general population to study prevalence of late cognitive impairment and associations with initial symptoms. We invited patients with PCR-confirmed COVID-19. A postal questionnaire addressed basic demographics, initial COVID-19 symptoms and co-morbidity about 4 months after diagnosis. About 7 months later, we conducted cognitive tests using the Cambridge Neuropsychological Test Automated Battery, comprising four tests for short-term memory, attention and executive function. We present descriptive statistics using z-scores relative to UK population norms and defined impairment as z-score <-1.5. We used multivariable logistic regression with impairment as outcome. Continuous domain scores were analysed by multiple linear regression. Of the initial 458 participants; 305 were invited, and 234 (77%) completed cognitive testing. At median 11 (range 8–13) months after PCR positivity, cognitive scores for short term memory, visuospatial processing, learning and attention were lower than norms (p≤0.001). In each domain, 4–14% were cognitively impaired; 68/232 (29%) were impaired in ≥ 1 of 4 tests. There was no association between initial symptom severity and impairment. Multivariable linear regression showed association between spatial working memory and initial symptom load (6–9 symptoms vs. 0–5, coef. 4.26, 95% CI: 0.65; 7.86). No other dimension scores were associated with symptom load. At median 11 months after out-of-hospital SARS-Cov-2 infection, minor cognitive impairment was seen with little association between COVID-19 symptom severity and outcome.

Does COVID-19 related symptomatology indicate a transdiagnostic neuropsychiatric disorder? - Multidisciplinary implications

The clinical presentation that emerges from the extensive coronavirus disease 2019 (COVID-19) mental health literature suggests high correlations among many conventional psychiatric diagnoses. Arguments against the use of multiple comorbidities for a single patient have been published long before the pandemic. Concurrently, diagnostic recommendations for use of transdiagnostic considerations for improved treatment have been also published in recent years. In this review, we pose the question of whether a transdiagnostic mental health disease, including psychiatric and neuropsychiatric symptomology, has emerged since the onset of the pandemic. There are many attempts to identify a syndrome related to the pandemic, but none of the validated scales is able to capture the entire psychiatric and neuropsychiatric clinical presentation in infected and non-infected individuals. These scales also only marginally touch the issue of etiology and prevalence. We suggest a working hypothesis termed Complex Stress Reaction Syndrome (CSRS) representing a global psychiatric reaction to the pandemic situation in the general population (Type A) and a neuropsychiatric reaction in infected individuals (Type B) which relates to neurocognitive and psychiatric features which are part (excluding systemic and metabolic dysfunctions) of the syndrome termed in the literature as long COVID. We base our propositions on multidisciplinary scientific data regarding mental health during the global pandemic situation and the effects of viral infection reviewed from Google Scholar and PubMed between February 1, 2022 and March 10, 2022. Search in-clusion criteria were “mental health”, “COVID-19” and “Long COVID”, English language and human studies only. We suggest that this more comprehensive way of understanding COVID-19 complex mental health reactions may promote better prevention and treatment and serve to guide implementation of recommended administrative regulations that were recently published by the World Psychiatric Association. This review may serve as a call for an international investigation of our working hypothesis.

Elevation of neural injury markers in patients with neurologic sequelae after hospitalization for SARS-CoV-2 infection

Patients with SARS-CoV-2 infection (COVID-19) risk developing long-term neurologic symptoms after infection. Here, we identify biomarkers associated with neurologic sequelae one year after hospitalization for SARS-CoV-2 infection. SARS-CoV-2-positive patients were followed using post-SARS-CoV-2 online questionnaires and virtual visits. Hospitalized adults from the pre-SARS-CoV-2 era served as historical controls. 40% of hospitalized patients develop neurological sequelae in the year after recovery from acute COVID-19 infection. Age, disease severity, and COVID-19 infection itself was associated with additional risk for neurological sequelae in our cohorts. Glial fibrillary astrocytic protein (GFAP) and neurofilament light chain (NF-L) were significantly elevated in SARS-CoV-2 infection. After adjusting for age, sex, and disease severity, GFAP and NF-L remained significantly associated with longer term neurological symptoms in patients with SARS-CoV-2 infection. GFAP and NF-L warrant exploration as biomarkers for long-term neurologic complications after SARS-CoV-2 infection.

Long COVID endotheliopathy: hypothesized mechanisms and potential therapeutic approaches

SARS-CoV-2-infected individuals may suffer a multi-organ system disorder known as "long COVID" or post-acute sequelae of SARS-CoV-2 infection (PASC). There are no standard treatments, the pathophysiology is unknown, and incidence varies by clinical phenotype. Acute COVID-19 correlates with biomarkers of systemic inflammation, hypercoagulability, and comorbidities that are less prominent in PASC. Macrovessel thrombosis, a hallmark of acute COVID-19, is less frequent in PASC. Female sex at birth is associated with reduced risk for acute COVID-19 progression, but with increased risk of PASC. Persistent microvascular endotheliopathy associated with cryptic SARS-CoV-2 tissue reservoirs has been implicated in PASC pathology. Autoantibodies, localized inflammation, and reactivation of latent pathogens may also be involved, potentially leading to microvascular thrombosis, as documented in multiple PASC tissues. Diagnostic assays illuminating possible therapeutic targets are discussed.

Physical, psychological and cognitive profile of post-COVID conditions in healthcare workers, Quebec, Canada

Background

The prevalence of post-COVID conditions (PCC) and associated physical, psychological and cognitive symptoms was assessed among Quebec healthcare workers (HCWs) with COVID-19.

Methods

This case-control study compared 6061 symptomatic HCWs with PCR-confirmed COVID-19 between July 2020 and May 2021 with a random sample of 4390 symptomatic HCWs who were test-negative controls. The prevalence of physical symptoms lasting ≥4 weeks (PCC4w) or ≥12 weeks (PCC12w) was estimated among hospitalized and non-hospitalized cases. In multivariate models, sociodemographic and clinical characteristics, as well as vaccine history, were evaluated as potential risk factors. Prevalence ratios compared four aspects of self-reported cognitive dysfunction among PCC cases to controls, adjusting for psychological distress and fatigue.

Results

PCC4w and PCC12w prevalences of 46% (2,746/5,943) and 40% (653/1,746), respectively, were observed among non-hospitalized cases and 76% (90/118) and 68% (27/37), respectively, among hospitalized cases. Hospitalization, female sex and age were associated with higher PCC risk.

A substantial proportion of non-hospitalized PCC4w cases often or very often reported cognitive dysfunction, including concentration (33%) or organizing (23%) difficulties, forgetfulness (20%) and loss of necessary items (10%). All four aspects of cognitive dysfunction were associated with PCC4w symptoms, psychological distress and fatigue.

Conclusion

PCC may be a frequent sequela of ambulatory COVID-19 in working-age adults, with important effects on cognition. With so many HCWs infected, the implications for quality healthcare delivery could be profound if cognitive dysfunction and other severe PCC symptoms persist in a professionally-disabling way. Further evaluation of PCC prevalence and prognosis is warranted.

Persistent neurological manifestations in long COVID-19 syndrome: A systematic review and meta-analysis

Background

Several studies have reported prolonged symptoms especially neurological symptoms following acute infection in patients with COVID-19, known as long COVID-19. There are only few studies investigating this population and relatively less known, including nervous system involvement. A systematic review and meta-analysis of these studies are required to understanding the prevalence of persistent neurological manifestations after COVID-19.

Objective

To conduct a systematic review and meta-analysis on the persistent neurological manifestations in COVID-19 survivors.

Methods

Authors conducted a literature search through PubMed and MedRxiv from January 1st, 2020 to October 2021 according to PRISMA guideline. Furthermore, the authors added additional sources by reviewing related references. Studies presenting the neurologic features of long COVID-19 patients in their data were included. Case reports and case series also included in this review. The quality of the studies was assessed based on the Oxford Centre for Evidence-Based Medicine guidelines. Selected studies were included in the meta-analysis of proportion and heterogeneity test.

Findings

From 128 identified studies, 36 were eligible, with 9944 participants included. Most of the included studies had mean duration of follow-up after COVID-19 onset of less than 6 months. Fatigue was the most common (52.8%, 95%CI 19.9 – 84.4) symptoms of long COVID, followed by cognitive disorder (35.4%, 95%CI 2.1 – 81.7); paresthesia (33.3%, 95%CI 2.7 – 76.6); sleep disorder (32.9%, 95%CI 6.5 – 67.4); musculoskeletal pain (27.8%, 95%CI 12.7 – 46); and dizziness (26.4%, 95%CI 4.6 – 57.9).

Conclusion

Neurological manifestations are prevalent and persisting in patients with long COVID. The duration of the symptoms are vary among literatures. However, the frequency are mostly observed during the first six months after the illness onset.

High-density EEG sleep correlates of cognitive and affective impairment at 12-month follow-up after COVID-19

Objective

To disentangle the pathophysiology of cognitive/affective impairment in Coronavirus Disease-2019 (COVID-19), we studied long-term cognitive and affective sequelae and sleep high-density electroencephalography (EEG) at 12-month follow-up in people with a previous hospital admission for acute COVID-19.

Methods

People discharged from an intensive care unit (ICU) and a sub-intensive ward (nonICU) between March and May 2020 were contacted between March and June 2021. Participants underwent cognitive, psychological, and sleep assessment. High-density EEG recording was acquired during a nap. Slow and fast spindles density/amplitude/frequency and source reconstruction in brain gray matter were extracted. The relationship between psychological and cognitive findings was explored with Pearson correlation.

Results

We enrolled 33 participants ( 17 nonICU) and 12 controls. We observed a lower Physical Quality of Life index, higher post-traumatic stress disorder (PTSD) score, and a worse executive function performance in nonICU participants. Higher PTSD and Beck Depression Inventory scores correlated with lower executive performance. The same group showed a reorganization of spindle cortical generators.

Conclusions

Our results show executive and psycho-affective deficits and spindle alterations in COVID-19 survivors – especially in nonICU participants – after 12 months from discharge.

Significance

These findings may be suggestive of a crucial contribution of stress experienced during hospital admission on long-term cognitive functioning.

Neurocognitive screening in patients following SARS-CoV-2 infection: tools for triage

Background

Cognitive complaints are common in patients recovering from Coronavirus Disease 2019 (COVID-19), yet their etiology is often unclear. We assess factors that contribute to cognitive impairment in ambulatory versus hospitalized patients during the sub-acute stage of recovery.

Methods

In this cross-sectional study, participants were prospectively recruited from a hospital-wide registry. All patients tested positive for SARS-CoV-2 infection using a real-time reverse transcriptase polymerase-chain-reaction assay. Patients ≤ 18 years-of-age and those with a pre-existing major neurocognitive disorder were excluded. Participants completed an extensive neuropsychological questionnaire and a computerized cognitive screen via remote telemedicine platform. Rates of subjective and objective neuropsychological impairment were compared between the ambulatory and hospitalized groups. Factors associated with impairment were explored separately within each group.

Results

A total of 102 patients (76 ambulatory, 26 hospitalized) completed the symptom inventory and neurocognitive tests 24 ± 22 days following laboratory confirmation of SARS-CoV-2 infection. Hospitalized and ambulatory patients self-reported high rates of cognitive impairment (27–40%), without differences between the groups. However, hospitalized patients showed higher rates of objective impairment in visual memory (30% vs. 4%; p = 0.001) and psychomotor speed (41% vs. 15%; p = 0.008). Objective cognitive test performance was associated with anxiety, depression, fatigue, and pain in the ambulatory but not the hospitalized group.

Conclusions

Focal cognitive deficits are more common in hospitalized than ambulatory patients. Cognitive performance is associated with neuropsychiatric symptoms in ambulatory but not hospitalized patients. Objective neurocognitive measures can provide essential information to inform neurologic triage and should be included as endpoints in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02817-9.

Global slowness and increased intra-individual variability are key features of attentional deficits and cognitive fluctuations in post COVID-19 patients

Fatigue, attentional deficits and cognitive fluctuations are the most characterizing symptoms of neurological involvement in Post COVID-19 syndrome (PCS). As the intraindividual variability (IIV) in cognitive performances has been recognized as a hallmark of brain-related disorders associated with cognitive deficits, it could be an interesting measure to elucidate the mechanisms subtending both the attentive impairment and the cognitive fluctuations in these patients. By referring to IIV analysis of Reaction Times (RTs), the present study aims to define the attentive impairment and its relation to fluctuations and fatigue, in patients suffering from Post COVID-19 neurological symptoms. 74 patients were enrolled. They underwent an extensive clinical and neuropsychological assessments, as well as computerized Sustained Attention and Stroop tasks. For studying IIV, RTs distributions of performances in computerized tasks were fitted with ex-Gaussian distribution, for obtaining the τ values. Finally, the Resting Motor Threshold (RMT) was also collected to estimate cortical excitability. 29 healthy volunteers served as controls. Patients showed poorer scores in Montreal Cognitive Assessment and higher RMT, in comparison with controls. In Sustained Attention Task, Mean, µ, σ and τ values were significantly higher in PCS patients (p value =  < 0.0001; 0.001; 0.018 and < 0.0001, respectively). Repeated measures ANOVA comparing the RTs mean in Stroop task within-subject and between-subjects revealed significant condition and group effect (p < 0.0001 both) and significant interaction (p = 0.005), indicating worst performances in patients. The mean of the derived interference value was significantly higher in PCS patients than in controls (p = 0.036). Patients suffering from PCS show deficits in attention, both in the sustained and executive components. Both high RTs means and high IIV subtend these deficits and could explain the often-complained cognitive fluctuations in this population.

Neurocognitive and Psychosocial Characteristics of Pediatric Patients With Post-Acute/Long-COVID: A Retrospective Clinical Case Series

Objective

Studies suggest a large number of patients have persistent symptoms following COVID-19 infection—a condition termed “long COVID.” Although children and parents often report cognitive difficulties after COVID, very few if any studies have been published including neuropsychological testing.

Methods

A retrospective chart review was completed for the first 18 patients referred for a neuropsychological evaluation from a multidisciplinary pediatric post-COVID clinic. The neuropsychological screening battery assessed verbal fluency and category switching, attention, working memory, processing speed, and verbal learning and memory. Patients’ caregivers also completed standardized questionnaires regarding day-to-day mood and behavior.

Results

At intake, the most common neurologic symptoms reported by caregivers were attention problems (83.3%), fatigue/lethargy (77.7%), sleep disturbance (77.7%), dizziness/vertigo (72.2%), and headaches (72.2%). On rating scales, most caregivers endorsed concerns for depressed mood and anxiety (14/15 and 12/15). A large proportion of patients had difficulties with attention (9/18) and depressed mood/anxiety (13/18) before COVID. On cognitive testing, the majority of the patients performed within or above broad average range (≥16th percentile) across most domains. However, a little over half of the patients performed below average on auditory attention measures.

Conclusions

Within our clinically referred sample, children who reported lingering cognitive symptoms after COVID-19 often had a preexisting history of attention and/or mood and anxiety concerns. Many of these patients performed below average in attention testing, but it remains to be seen whether this was due to direct effects of COVID, physical symptoms, and/or preexisting difficulties with attention or mood/anxiety.

Dendrimer nanotherapy for severe COVID-19 attenuates inflammation and neurological injury markers and improves outcomes in a phase2a clinical trial

Hyperinflammation triggered by SARS-CoV-2 is a major cause of disease severity, with activated macrophages implicated in this response. OP-101, a hydroxyl-polyamidoamine dendrimer-N-acetylcysteine conjugate that specifically targets activated macrophages, improves outcomes in preclinical models of systemic inflammation and neuroinflammation. In this multicenter, randomized, double-blind, placebo-controlled, adaptive phase 2a trial, we evaluated safety and preliminary efficacy of OP-101 in patients with severe COVID-19. Twenty-four patients classified as having severe COVID-19 with a baseline World Health Organization seven-point ordinal scale of ≥5 were randomized to receive a single intravenous dose of placebo (n = 7 patients) or OP-101 at 2 (n = 6), 4 (n = 6), or 8 mg/kg (n = 5 patients). All study participants received standard of care, including corticosteroids. OP-101 at 4 mg/kg was better than placebo at decreasing inflammatory markers; OP-101 at 4 and 8 mg/kg was better than placebo at reducing neurological injury markers, (neurofilament light chain and glial fibrillary acidic protein). Risk for the composite outcome of mechanical ventilation or death at 30 and 60 days after treatment was 71% (95% CI: 29%, 96%) for placebo and 18% (95% CI: 4%, 43%; P = 0.021) for the pooled OP-101 treatment arms. At 60 days, 3 of 7 patients given placebo and 14 of 17 OP-101-treated patients were surviving. No drug-related adverse events were reported. These data show that OP-101 was well tolerated and may have potential to treat systemic inflammation and neuronal injury, reducing morbidity and mortality in hospitalized patients with severe COVID-19.

Neuromuskuläre Manifestationen beim Long-COVID-Syndrom

Unter dem Long-COVID(„coronavirus disease“)-Syndrom werden Beschwerden zusammengefasst, die nach einer akuten SARS-CoV-2(„severe acute respiratory syndrome coronavirus type 2“)-Infektion auftreten, über einen Zeitraum von mehreren Wochen anhalten und nicht durch eine andere Diagnose erklärt werden können. Long-COVID wird als Multiorganmanifestation aufgefasst. In diesem Übersichtsartikel wird die Datenlage hinsichtlich neuromuskulärer Manifestationen des Long-COVID-Syndroms summiert und anhand von Kriterien wie Effektstärke, Plausibilität, Kohärenz und experimentelle Evidenz bewertet. Bisher sind vor allem Myalgien und eine autonome Dysfunktion (u. a. das posturale Tachykardiesyndrom) als neuromuskuläre Symptome von Long-COVID beschrieben worden. Die bisherige Evidenz ist allerdings gering: Neben einer sehr heterogenen Methodik und unterschiedlichen Definitionen in den klinischen Long-COVID-Studien fehlen schlüssige experimentelle Daten, die die beschriebenen Symptome als spezifische Langzeitfolge von COVID-19 belegen.

Anti-nucleocapsid antibody levels and pulmonary comorbid conditions are linked to post-COVID-19 syndrome

BACKGROUNDProlonged symptoms after SARS-CoV-2 infection are well documented. However, which factors influence development of long-term symptoms, how symptoms vary across ethnic groups, and whether long-term symptoms correlate with biomarkers are points that remain elusive.METHODSAdult SARS-CoV-2 reverse transcription PCR-positive (RT-PCR-positive) patients were recruited at Stanford from March 2020 to February 2021. Study participants were seen for in-person visits at diagnosis and every 1-3 months for up to 1 year after diagnosis; they completed symptom surveys and underwent blood draws and nasal swab collections at each visit.RESULTSOur cohort (n = 617) ranged from asymptomatic to critical COVID-19 infections. In total, 40% of participants reported at least 1 symptom associated with COVID-19 six months after diagnosis. Median time from diagnosis to first resolution of all symptoms was 44 days; median time from diagnosis to sustained symptom resolution with no recurring symptoms for 1 month or longer was 214 days. Anti-nucleocapsid IgG level in the first week after positive RT-PCR test and history of lung disease were associated with time to sustained symptom resolution. COVID-19 disease severity, ethnicity, age, sex, and remdesivir use did not affect time to sustained symptom resolution.CONCLUSIONWe found that all disease severities had a similar risk of developing post-COVID-19 syndrome in an ethnically diverse population. Comorbid lung disease and lower levels of initial IgG response to SARS-CoV-2 nucleocapsid antigen were associated with longer symptom duration.TRIAL REGISTRATIONClinicalTrials.gov, NCT04373148.FUNDINGNIH UL1TR003142 CTSA grant, NIH U54CA260517 grant, NIEHS R21 ES03304901, Sean N Parker Center for Allergy and Asthma Research at Stanford University, Chan Zuckerberg Biohub, Chan Zuckerberg Initiative, Sunshine Foundation, Crown Foundation, and Parker Foundation.

Exposure to phenytoin associates with a lower risk of post-COVID cognitive deficits: a cohort study

Post-COVID cognitive deficits (often referred to as ‘brain fog’) are common and have large impacts on patients’ level of functioning. No specific intervention exists to mitigate this burden.

This study tested the hypothesis, inspired by recent experimental research, that post-COVID cognitive deficits can be prevented by inhibiting receptor-interacting protein kinase. Using electronic health record data, we compared the cognitive outcomes of propensity score-matched cohorts of patients with epilepsy taking phenytoin (a commonly used receptor-interacting protein kinase inhibitor) versus valproate or levetiracetam at the time of COVID-19 diagnosis. Patients taking phenytoin at the time of COVID-19 were at a significantly lower risk of cognitive deficits in the 6 months after COVID-19 infection than a matched cohort of patients receiving levetiracetam (hazard ratio 0.78, 95% confidence interval 0.63–0.97, P = 0.024) or valproate (hazard ratio 0.73, 95% confidence interval 0.58–0.93, P = 0.011). In secondary analyses, results were robust when controlling for subtype of epilepsy, and showed specificity to cognitive deficits in that similar associations were not seen with other ‘long-COVID’ outcomes such as persistent breathlessness or pain. These findings provide pharmacoepidemiological support for the hypothesis that receptor-interacting protein kinase signaling is involved in post-COVID cognitive deficits. These results should prompt empirical investigations of receptor-interacting protein kinase inhibitors in the prevention of post-COVID cognitive deficits.

COVID-19 associated cognitive impairment: A systematic review

INTRODUCTION

COVID-19 has a wide range of clinical manifestations. Neurological manifestations in COVID-19 patients were demonstrated during the pandemic, including cognitive impairment. This study aimed to determine any relationship between COVID-19 and cognitive complaints, such as dementia, mild cognitive impairment (MCI), or subjective cognitive decline (SCD).

METHODS

We performed a systematic review of MEDLINE via Ebsco, Cochrane EMBASE, SCOPUS, and LILACS electronic databases of observational studies with COVID-19 patients confirmed by serology or PCR who developed new cognitive impairment or deteriorated from previous cognitive impairment after infection. This review protocol was recorded on PROSPERO with registration number CRD 42021241590.

RESULTS

A total of 3.520 articles were retrieved and read. Twenty-two studies were selected for our review. A wide range of cognitive assessment tools (n = 25) was used. The most described affected domains in these studies were executive functions, attention, and episodic memory. Thirteen studies showed a pattern of cognitive impairment in processing speed, inattention, or executive dysfunction assessed through working memory.

CONCLUSION

This review highlights the high frequency of cognitive impairment after COVID-19 infection. However, we were unable to differentiate whether the cognitive impairment found corresponded to mild cognitive impairment or dementia through data from selected studies, and this issue serves as one objective of future studies to be addressed on this topic.

Sleep spindles changes in people with previous COVID-19 infection

Stage 2 sleep spindles are considered useful biomarkers for the integrity of the central nervous system and for cognitive and memory skills. We investigated sleep spindles patterns in subjects after 12 months of their hospitalization in the intensive care unit (ICU) of the Padova Teaching Hospital due to COVID-19 between March and November 2020. Before the nap, participants (13 hospitalized in ICU - ICU; 9 hospitalized who received noninvasive ventilation - nonlCU; 9 age and sex-matched healthy controls - CTRL, i.e., not infected by COVID-19) underwent a cognitive and psychological as-sessment. During the nap, high-density electroencephalography (EEG) recordings were acquired. Slow (i.e., [9]-[12] Hz) and fast (i.e.,]12-16] Hz) spindles were automatically detected. Spindle density and spindle source reconstruction in brain grey matter were extracted. The psychological assessment revealed a statistical difference comparing CTRL and nonlCU in Beck Depression Inventory score and in the Physical Quality of Life index (p_value = 0.03). The cognitive assessment revealed a trend of worsening results in executive functions in COVID-19 survivors. Slow spindle density significantly decreased comparing CTRL to COVID-19 survivors (p_value= 0.001). There were statistically significant differences in EEG source-waveforms fast spindle amplitude onset among the three groups, mainly between CTRL and nonlCU. Clinical Relevance- Our results suggest that nonlCU were more susceptible to the hospitalization experience than ICU participants with a slight effect on cognitive tests. This impacted the spindle generation revealing a decreased density of slow spindles and affecting the generators of fast spindles in COVID-19 survivors especially in nonlCU.

Identifying Profiles and Symptoms of Patients With Long COVID in France: Data Mining Infodemiology Study Based on Social Media

BACKGROUND

Long COVID-a condition with persistent symptoms post COVID-19 infection-is the first illness arising from social media. In France, the French hashtag #ApresJ20 described symptoms persisting longer than 20 days after contracting COVID-19. Faced with a lack of recognition from medical and official entities, patients formed communities on social media and described their symptoms as long-lasting, fluctuating, and multisystemic. While many studies on long COVID relied on traditional research methods with lengthy processes, social media offers a foundation for large-scale studies with a fast-flowing outburst of data.

OBJECTIVE

We aimed to identify and analyze Long Haulers' main reported symptoms, symptom co-occurrences, topics of discussion, difficulties encountered, and patient profiles.

METHODS

Data were extracted based on a list of pertinent keywords from public sites (eg, Twitter) and health-related forums (eg, Doctissimo). Reported symptoms were identified via the MedDRA dictionary, displayed per the volume of posts mentioning them, and aggregated at the user level. Associations were assessed by computing co-occurrences in users' messages, as pairs of preferred terms. Discussion topics were analyzed using the Biterm Topic Modeling; difficulties and unmet needs were explored manually. To identify patient profiles in relation to their symptoms, each preferred term's total was used to create user-level hierarchal clusters.

RESULTS

Between January 1, 2020, and August 10, 2021, overall, 15,364 messages were identified as originating from 6494 patients of long COVID or their caregivers. Our analyses revealed 3 major symptom co-occurrences: asthenia-dyspnea (102/289, 35.3%), asthenia-anxiety (65/289, 22.5%), and asthenia-headaches (50/289, 17.3%). The main reported difficulties were symptom management (150/424, 35.4% of messages), psychological impact (64/424,15.1%), significant pain (51/424, 12.0%), deterioration in general well-being (52/424, 12.3%), and impact on daily and professional life (40/424, 9.4% and 34/424, 8.0% of messages, respectively). We identified 3 profiles of patients in relation to their symptoms: profile A (n=406 patients) reported exclusively an asthenia symptom; profile B (n=129) expressed anxiety (n=129, 100%), asthenia (n=28, 21.7%), dyspnea (n=15, 11.6%), and ageusia (n=3, 2.3%); and profile C (n=141) described dyspnea (n=141, 100%), and asthenia (n=45, 31.9%). Approximately 49.1% of users (79/161) continued expressing symptoms after more than 3 months post infection, and 20.5% (33/161) after 1 year.

CONCLUSIONS

Long COVID is a lingering condition that affects people worldwide, physically and psychologically. It impacts Long Haulers' quality of life, everyday tasks, and professional activities. Social media played an undeniable role in raising and delivering Long Haulers' voices and can potentially rapidly provide large volumes of valuable patient-reported information. Since long COVID was a self-titled condition by patients themselves via social media, it is imperative to continuously include their perspectives in related research. Our results can help design patient-centric instruments to be further used in clinical practice to better capture meaningful dimensions of long COVID.

The unique contribution of depression to cognitive impairment in Post-Acute Sequelae of SARS-CoV-2 infection

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with significant cognitive impairment and increased risk for mental health comorbidities. This study aimed to identify specific associations between cognitive impairment, self-reported disruptions in memory, and psychiatric symptoms including depression, anxiety, posttraumatic stress disorder (PTSD), and perceived sleep concerns.

Methods

Data collected from all consecutive patients with Post-Acute Sequelae of SARS-CoV-2 infection (PASC) who presented to a dedicated Post-COVID Clinic were used to evaluate whether certain psychiatric symptoms were more strongly associated with cognitive impairment and self-reported memory disturbances.

Results

Univariate and multivariable analyses revealed that depression symptom severity was significantly associated with the severity of cognitive impairment among patients with PASC. This association was driven primarily by lower performance on verbal fluency, attention, and delayed recall tasks among patients with higher depression symptoms severity. Perceived sleep concerns were an important predictor of self-reported memory disturbances. Conversely, neither PTSD symptom severity nor anxiety symptom severity were significant predictors of cognitive impairment or self-reported memory disturbances.

Conclusions

These findings have important clinical implications for justifying the need for screening patients with PASC for both depression and cognitive impairment.

•

Depression was positively associated with cognitive impairment post-COVID-19 infection.

•

Depression was associated with lower performance on verbal fluency, attention, and delayed recall.

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Perceived sleep concerns predicted self-reported memory disturbances.

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Neither PTSD nor anxiety predicted cognitive impairment memory.

Neuropsychological manifestations of long COVID in hospitalized and non-hospitalized Brazilian Patients

BACKGROUND

There has been a significant increase in number of patients seeking neuropsychological rehabilitation months after the acute phase of COVID-19 infection.

OBJECTIVE

Identify the cognitive and psychiatric disorders in patients with long COVID or Post-Acute Sequelae of COVID (PASC) and explore the association between disease severity during the acute phase and persistent neuropsychological manifestations.

METHODS

614 adults were assessed an average of eight months post-infection. Participants were, on average, 47.6 y.o., who sought rehabilitation for neuropsychological problems. Patients were evaluated using the Barrow Neurological Institute Screen for Higher Cerebral Functions (BNIS), Phonemic Verbal Fluency and Clock Drawing tests (NEUPSILIN) for executive functions, and the Hospital Anxiety and Depression Scale (HADS).

RESULTS

The BNIS score was significantly below reference values in all subscales, especially affect and memory. Verbal Fluency and Clock Drawing subtest results were also lower. Patients with PASC tested high for anxiety/depression, but there was no statistically significant relationship between HADS and BNIS scores. Neuropsychological evaluations showed no differences in cognitive or psychiatric profiles between hospitalized and non-hospitalized patients.

CONCLUSIONS

Neuropsychological results suggest executive function problems and high incidence of anxiety/depression, irrespective of acute-phase severity, underscoring a need for neurorehabilitation programs while providing data for public policy initiatives.

Clinical Characteristics and Mechanisms of Musculoskeletal Pain in Long COVID

Objective

Musculoskeletal (MSK) pain is being increasingly reported by patients as one of the most common persistent symptoms in post-COVID-19 syndrome or Long COVID. However, there is a lack of understanding of its prevalence, characteristics, and underlying pathophysiological mechanisms. The objective of this review is to identify and describe the features and characteristics of MSK pain in Long COVID patients.

Methods

The narrative review involved a literature search of the following online databases: MEDLINE (OVID), EMBASE (OVID), CINAHL, PsyclNFO, and Web of Science (December 2019 to February 2022). We included observational studies that investigated the prevalence, characteristics, risk factors and mechanisms of MSK pain in Long COVID. After screening and reviewing the initial literature search results, a total of 35 studies were included in this review.

Results

The overall reported prevalence of MSK pain in Long COVID ranged widely from 0.3% to 65.2%. The pain has been reported to be localized to a particular region or generalized and widespread. No consistent pattern of progression of MSK pain symptoms over time was identified. Female gender and higher BMI could be potential risk factors for Long COVID MSK pain, but no clear association has been found with age and ethnicity. Different pathophysiological mechanisms have been hypothesized to contribute to MSK pain in Long COVID including increased production of proinflammatory cytokines, immune cell hyperactivation, direct viral entry of neurological and MSK system cells, and psychological factors.

Conclusion

MSK pain is one of the most common symptoms in Long COVID. Most of the current literature on Long COVID focuses on reporting the prevalence of persistent MSK pain. Studies describing the pain characteristics are scarce. The precise mechanism of MSK pain in Long COVID is yet to be investigated. Future research must explore the characteristics, risk factors, natural progression, and underlying mechanisms of MSK pain in Long COVID.

A Concise Occupational Mental Health Screening Tool for South African Workplaces

Mental health in the workplace is becoming of ever greater importance. General occupational health surveillance programmes are already in widespread use, with established referral systems for treatment and rehabilitation, and the same mechanisms could be expanded to include mental health screening and intervention. This study aimed to develop a concise composite mental health screening tool, based on analysis of existing data, for application in routine occupational health surveillance in South Africa. Data from workplace occupational health surveillance programs from 2,303 participants were analysed. Participants completed a number of questions/scaled items collated into a survey format, and partook in an interview with a psychologist. The data was analysed using frequency of positive self-reports, Chi square to calculate associations with outcomes, Receiver Operator Characteristic curve analysis to explore predictive ability, and binomial logistic regression to calculate the relative contribution of markers to outcomes. An exploratory factor analysis was further conducted on identified items. A general workplace model with 14 markers (and a maritime workplace model with 17 markers) were identified. The factor analysis suggested their organisation into five domains (similar for both models), namely neurocognitive health, common mental disorders, history of adaptation in occupational specific contexts, family-work interface, and stress overload. The study’s data-driven approach proposed a concise composite screener with less than 50 items, comprising five domains. This tool appears useful in identifying employees at risk for workplace injuries or poor mental health outcomes, and could be applied to related workplace settings in South Africa.

Longitudinal evaluation of neurologic-post acute sequelae SARS-CoV-2 infection symptoms

OBJECTIVE

To assess the initial features and evolution of neurologic Postacute Sequelae of SARS-CoV-2 infection (neuro-PASC) in patients with and without prior neurologic disease.

METHODS

Participants with neurologic symptoms following acute SARS-CoV-2 infection were recruited from October 9, 2020 to October 11, 2021. Clinical data included a SARS-CoV-2 infection history, neurologic review of systems, neurologic exam, Montreal cognitive assessment (MoCA), and symptom-based self-reported surveys at baseline (conducted after acute infection) and 6-month follow-up assessments.

RESULTS

Fifty-six participants (69% female, mean age 50 years, 29% with prior neurologic disease such as multiple sclerosis) were enrolled, of which 27 had completed the 6-month follow-up visit in this ongoing study. SARS-CoV-2 infection severity was largely described as mild (39.3%) or moderate (42.9%). At baseline, following acute infection, the most common neurologic symptoms were fatigue (89.3%) and headaches (80.4%). At the 6-month follow-up, memory impairment (68.8%) and decreased concentration (61.5%) were the most prevalent, though on average all symptoms showed a reduction in reported severity score at the follow-up. Complete symptom resolution was reported in 33.3% of participants by 6 months. From baseline to 6 months, average MoCA scores improved overall though 26.3% of participants' scores decreased. A syndrome consisting of tremor, ataxia, and cognitive dysfunction (PASC-TAC) was observed in 7.1% of patients.

INTERPRETATION

Early in the neuro-PASC syndrome, fatigue and headache are the most commonly reported symptoms. At 6 months, memory impairment and decreased concentration were most prominent. Only one-third of participants had completed resolution of neuro-PASC at 6 months, although persistent symptoms trended toward improvement at follow-up.

Medicinal Herbs in the Relief of Neurological, Cardiovascular, and Respiratory Symptoms after COVID-19 Infection A Literature Review

COVID-19 infection causes complications, even in people who have had a mild course of the disease. The most dangerous seem to be neurological ailments: anxiety, depression, mixed anxiety–depressive (MAD) syndromes, and irreversible dementia. These conditions can negatively affect the respiratory system, circulatory system, and heart functioning. We believe that phytotherapy can be helpful in all of these conditions. Clinical trials confirm this possibility. The work presents plant materials (Valeriana officinalis, Melissa officinalis, Passiflora incarnata, Piper methysticum, Humulus lupulus, Ballota nigra, Hypericum perforatum, Rhodiola rosea, Lavandula officinalis, Paullinia cupana, Ginkgo biloba, Murraya koenigii, Crataegus monogyna and oxyacantha, Hedera helix, Polygala senega, Pelargonium sidoides, Lichen islandicus, Plantago lanceolata) and their dominant compounds (valeranon, valtrate, apigenin, citronellal, isovitexin, isoorientin, methysticin, humulone, farnesene, acteoside, hypericin, hyperforin, biapigenin, rosavidin, salidroside, linalool acetate, linalool, caffeine, ginkgolide, bilobalide, mihanimbine, epicatechin, hederacoside C,α-hederine, presegenin, umckalin, 6,7,8-trixydroxybenzopyranone disulfate, fumaroprotocetric acid, protolichesteric acid, aucubin, acteoside) responsible for their activity. It also shows the possibility of reducing post-COVID-19 neurological, respiratory, and cardiovascular complications, which can affect the functioning of the nervous system.

Myopathy as a cause of fatigue in long-term post-COVID-19 symptoms: Evidence of skeletal muscle histopathology

Background and purpose

Among post‐COVID‐19 symptoms, fatigue is reported as one of the most common, even after mild acute infection, and as the cause of fatigue, myopathy diagnosed by electromyography has been proposed in previous reports. This study aimed to explore the histopathological changes in patients with post‐COVID‐19 fatigue.

Methods

Sixteen patients (mean age = 46 years) with post‐COVID‐19 complaints of fatigue, myalgia, or weakness persisting for up to 14 months were included. In all patients, quantitative electromyography and muscle biopsies analyzed with light and electron microscopy were taken.

Results

Muscle weakness was present in 50% and myopathic electromyography in 75%, and in all patients there were histological changes. Muscle fiber atrophy was found in 38%, and 56% showed indications of fiber regeneration. Mitochondrial changes, comprising loss of cytochrome c oxidase activity, subsarcollemmal accumulation, and/or abnormal cristae, were present in 62%. Inflammation was found in 62%, seen as T lymphocytes and/or muscle fiber human leukocyte antigen ABC expression. In 75%, capillaries were affected, involving basal lamina and cells. In two patients, uncommon amounts of basal lamina were found, not only surrounding muscle fibers but also around nerves and capillaries.

Conclusions

The wide variety of histological changes in this study suggests that skeletal muscles may be a major target of SARS‐CoV‐2, causing muscular post‐COVID‐19 symptoms. The mitochondrial changes, inflammation, and capillary injury in muscle biopsies can cause fatigue in part due to reduced energy supply. Because most patients had mild–moderate acute affection, the new variants that might cause less severe acute disease could still have the ability to cause long‐term myopathy.

Mechanisms of Entry Into the Central Nervous System by Neuroinvasive Pathogens

BACKGROUND

The literature on neurological manifestations, cerebrospinal fluid analyses, and autopsies in patients with COVID-19 continues to grow. The proposed mechanisms for neurological disease in patients with COVID-19 include indirect processes such as inflammation, microvascular injury, and hypoxic-ischemic damage. An alternate hypothesis suggests direct viral entry of SARS-CoV-2 into the brain and cerebrospinal fluid, given varying reports regarding isolation of viral components from these anatomical sites.

EVIDENCE ACQUISITION

PubMed, Google Scholar databases, and neuroanatomical textbooks were manually searched and reviewed.

RESULTS

We provide clinical concepts regarding the mechanisms of viral pathogen invasion in the central nervous system (CNS); advances in our mechanistic understanding of CNS invasion in well-known neurotropic pathogens can aid in understanding how viruses evolve strategies to enter brain parenchyma. We also present the structural components of CNS compartments that influence viral entry, focusing on hematogenous and transneuronal spread, and discuss this evidence as it relates to our understanding of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2).

CONCLUSIONS

Although there is a paucity of data supporting direct viral entry of SARS-CoV-2 in humans, increasing our knowledge of the structural components of CNS compartments that block viral entry and pathways exploited by pathogens is fundamental to preparing clinicians and researchers for what to expect when a novel emerging virus with neurological symptoms establishes infection in the CNS, and how to design therapeutics to mitigate such an infection.

Behavioral problems of pediatric patients recovered from COVID-19 in Wuhan, China

Background

Coronavirus disease 2019 (COVID-19) is profoundly affecting lives around the globe. Previous studies on COVID-19 mainly focused on epidemiological, clinical, and radiological features of patients with confirmed infection. Little attention has been paid to the follow-up of recovered patients. As a vulnerable population to adverse events, the health status of the COVID-19 recovered pediatric patients is of great concern. We aimed to investigate the prevalence of behavioral problems among pediatric patients recovered from the COVID-19 in Wuhan, China.

Methods

A total of 122 children who were suspected or confirmed COVID-19 cases and hospitalized for treatment were enrolled in the study between April 2020 and May 2020 in Wuhan, China. We collected related information about hospitalization and discharge of the children and emotional symptoms of their parents through electronic medical records and questionnaire. The behavioral problems of children were examined by applying the parent-reported the Strengths and Difficulties Questionnaire (SDQ).

Results

The participant children were discharged from hospital after about two months. Among them, 76 (62%) were boys, and the mean age was 6.71 years old. The highest prevalence of behavioral problems among pediatric children with COVID-19 was for prosocial behavior (15%), followed by total difficulties (13%), emotional symptoms (11%), hyperactivity (10%), conduct problems (9%), and peer problems (1%). With regarding to their parents, 26% reported having symptoms of anxiety and 23% as having symptoms of depression. The scores of SDQ were higher in those children whose parents have emotional problems compared to parents without.

Conclusion

Long-term follow up studies on the psychological and behavioral problems of COVID-19 recovered children and their parents are warranted.

Postacute Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 Infection

Postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or long coronavirus disease (COVID) is an emerging syndrome characterized by multiple persisting or newly emergent symptoms following the acute phase of SARS-CoV-2 infection. For affected patients, these prolonged symptoms can have a relapsing and remitting course and may be associated with disability and frequent health care utilization. Although many symptom-driven treatments are available, management remains challenging and often requires a multidisciplinary approach. This article summarizes the emerging consensus on definitions, epidemiology, and pathophysiology of long COVID and discusses what is understood about prevention, evaluation, and treatment of this syndrome.

COVID-19 2022 update: transition of the pandemic to the endemic phase

COVID-19, which is caused by the SARS-CoV-2, has ravaged the world for the past 2 years. Here, we review the current state of research into the disease with focus on its history, human genetics and genomics and the transition from the pandemic to the endemic phase. We are particularly concerned by the lack of solid information from the initial phases of the pandemic that highlighted the necessity for better preparation to face similar future threats. On the other hand, we are gratified by the progress into human genetic susceptibility investigations and we believe now is the time to explore the transition from the pandemic to the endemic phase. The latter will require worldwide vigilance and cooperation, especially in emerging countries. In the transition to the endemic phase, vaccination rates have lagged and developed countries should assist, as warranted, in bolstering vaccination rates worldwide. We also discuss the current status of vaccines and the outlook for COVID-19.