Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health

Abstract:

Background: Long-COVID refers to ongoing, relapsing, or new symptoms present 30 or more days after Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. This study examined the prevalence and severity of neurologic symptoms at greater than 1 month following acute SARS-CoV-2 infection and the influence of pre-existing neurologic and psychiatric conditions, current depression and anxiety status, and hospitalization on the presence and severity of these symptoms.

Methods: This prospective cohort study recruited primarily self-referred Long-COVID participants with confirmed SARS-CoV-2 infection. Online questionnaires inquiring about pre-existing conditions, neurologic symptoms and their severity pre, during and post COVID-19, and current anxiety and depression screening were completed by 213 participants at a median time of 8 months after infection. Descriptive analyses and prevalence modeling were performed.

Results: The most frequent neurologic symptoms post COVID-19 were fatigue, concentration/memory difficulties, unrefreshed sleep, and dysarthria/word finding difficulties (73.2–86.4%). Neurologic symptoms were highly prevalent with significantly greater odds post COVID-19 compared to pre for all symptoms and higher prevalence at time periods farther from infection, including those implicit in fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome. Several severe neurologic symptoms were significantly more prevalent post COVID-19. Moderate to severe anxiety (34%) and depression (27%) were observed post COVID-19. Preexisting neurologic or psychiatric conditions did not demonstrate any significant difference in neurologic symptom prevalence post COVID-19. Those who met criteria for moderate or severe anxiety post COVID-19 had a significant difference in prevalence of fatigue, sensitivity to touch and unrefreshed sleep. Similarly, fatigue, concentration/memory difficulty and unrefreshed sleep were more prevalent in moderate to severe depression. There were no significant differences in neurologic symptom prevalence in a hospitalized group when compared to non- hospitalized.

Conclusion: Long-COVID has a high burden of long lasting and severe neurological sequelae. These sequelae are independent of pre-existing self-reported neurologic and psychiatric conditions, as well as previous hospitalization. Current moderate to severe anxiety and depression status can impact fatigue, cognition, and sleep post COVID-19. Focus on the biological impact of SARS-CoV-2 on the nervous system will be essential in ameliorating the tremendous symptom burden left in the wake of the COVID-19 pandemic.

Source: Huff Hanalise V. , Roberts Henry , Bartrum Elizabeth , Norato Gina , Grayson Nicholas , Fleig Katherine , Wilkerson Miciah J. , Stussman Barbara J. , Nath Avindra , Walitt Brian. Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health. Frontiers in Neurology, Volume 16 – 2025 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1562084 10.3389/fneur.2025.1562084 ISSN:1664-2295 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1562084/full (Full text)

Long-term neurological and cognitive impact of COVID-19: a systematic review and meta-analysis in over 4 million patients

Abstract:

Background: Neuropsychiatric symptoms emerged early in the COVID-19 pandemic as a key feature of the virus, with research confirming a range of neuropsychiatric manifestations linked to acute SARS-CoV-2 infection. However, the persistence of neurological symptoms in the post-acute and chronic phases remains unclear. This meta-analysis assesses the long-term neurological effects of COVID-19 in recovered patients, providing insights for mental health service planning.

Methods: A comprehensive literature search was conducted across five electronic databases: PubMed, Scopus, Web of Science, EBSCO, and CENTRAL, up to March 22, 2024. Studies evaluating the prevalence of long-term neurological symptoms in COVID-19 survivors with at least six months of follow-up were included. Pooled prevalence estimates, subgroup analyses, and meta-regression were performed, and publication bias was assessed.

Results: The prevalence rates for the different symptoms were as follows: fatigue 43.3% (95% CI [36.1-50.9%]), memory disorders 27.8% (95% CI [20.1-37.1%]), cognitive impairment 27.1% (95% CI [20.4-34.9%]), sleep disorders 24.4% (95% CI [18.1-32.1%]), concentration impairment 23.8% (95% CI [17.2-31.9%]), headache 20.3% (95% CI [15-26.9%]), dizziness 16% (95% CI [9.5-25.7%]), stress 15.9% (95% CI [10.2-24%]), depression 14.0% (95% CI [10.1-19.2%]), anxiety 13.2% (95% CI [9.6-17.9%]), and migraine 13% (95% CI [2.2-49.8%]). Significant heterogeneity was observed across all symptoms. Meta-regression analysis showed higher stress, fatigue, and headache in females, and increased stress and concentration impairment with higher BMI.

Conclusions: Neurological symptoms are common and persistent in COVID-19 survivors. This meta-analysis highlights the significant burden these symptoms place on individuals, emphasizing the need for well-resourced multidisciplinary healthcare services to support post-COVID recovery.

Source: Elboraay T, Ebada MA, Elsayed M, Aboeldahab HA, Salamah HM, Rageh O, Elmallahy M, AboElfarh HE, Mansour LS, Nabil Y, Eltawab AKA, Atwan H, Alkanj S. Long-term neurological and cognitive impact of COVID-19: a systematic review and meta-analysis in over 4 million patients. BMC Neurol. 2025 Jun 14;25(1):250. doi: 10.1186/s12883-025-04174-9. PMID: 40514644; PMCID: PMC12166599. https://pmc.ncbi.nlm.nih.gov/articles/PMC12166599/ (Full text)

Disruptions in serotonin- and kynurenine pathway metabolism in post-COVID: biomarkers and treatment

Introduction:

This opinion article attempts to connect knowledge about post-COVID syndrome (PCS) gained in neuropsychiatry and immunology. It discusses some misunderstandings about PCS in light of the interplay between the serotonergic system and the kynurenine pathway (KP). From a new perspective, potential biomarkers for further research and therapeutic targets are identified.

Due to the severity and extent of PCS, researchers are urgently searching for its causes and treatments. For neurocognitive and autonomic nervous system problems such as present in PCS, it is common to encounter dysregulated neurotransmitter systems. Among the neurotransmitters, serotonin plays a special role in the immune system and in regulating inflammatory responses by central and peripheral mechanisms (). Serotonin—also known as 5-hydroxytryptamine (5-HT)—is a neurotransmitter with a stimulating effect that influences memory, mood, self-confidence, sleep, emotion, orgasm and eating ().

Serotonin not only binds to serotonergic receptors on neurons, but also to receptors on immune cells (). Many studies indicate that serotonin and its receptors, especially 5-HT3 receptors (one of the serotonin receptors), are involved in the pathogenesis of chronic inflammatory conditions (). Therapeutic applications of 5-HT3 receptor antagonists for instance have been reported in rheumatoid arthritis (). An essential amino acid in the serotonin system and also in the KP is tryptophan, a precursor of both serotonin and kynurenine (see Figure 1) and part of a regular diet (). The KP is a pathway creating an important energy factor and is modulated in conditions as infection and stress (). Kynurenine regulates the balance between two types of thymus cells (T-cells): regulatory T-cells (Treg-cells), and subsets of T helper 17 cells (Th17 cells) that produce cytokines and have a signaling function ().

In this opinion article I address the question whether disruptions in the serotonin- and kynurenine pathway metabolism lead to new biomarkers and treatment in PCS.

Source: Rus CP. Disruptions in serotonin- and kynurenine pathway metabolism in post-COVID: biomarkers and treatment. Front Neurol. 2025 Feb 13;16:1532383. doi: 10.3389/fneur.2025.1532383. PMID: 40027165; PMCID: PMC11869386. https://pmc.ncbi.nlm.nih.gov/articles/PMC11869386/ (Full text)

Therapeutic Approaches to the Neurologic Manifestations of COVID-19

Abstract:

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.

Source: Graham EL, Koralnik IJ, Liotta EM. Therapeutic Approaches to the Neurologic Manifestations of COVID-19. Neurotherapeutics. 2022 Sep;19(5):1435-1466. doi: 10.1007/s13311-022-01267-y. Epub 2022 Jul 21. PMID: 35861926; PMCID: PMC9302225. https://pmc.ncbi.nlm.nih.gov/articles/PMC9302225/ (Full text)

Brainstem Reduction and Deformation in the 4th Ventricle Cerebellar Peduncles in Long COVID Patients: Insights into Neuroinflammatory Sequelae and “Broken Bridge Syndrome”

Abstract:

Post-COVID Syndrome (PCS), also known as Long COVID, is characterized by persistent and often debilitating neurological sequelae, including fatigue, cognitive dysfunction, motor deficits, and autonomic dysregulation (Dani et al., 2021). This study investigates structural and functional alterations in the brainstem and cerebellar peduncles of individuals with PCS using diffusion tensor imaging (DTI) and volumetric analysis. Forty-four PCS patients (15 bedridden) and 14 healthy controls underwent neuroimaging. Volumetric analysis focused on 22 brainstem regions, including the superior cerebellar peduncle (SCP), middle cerebellar peduncle (MCP), periaqueductal gray (PAG), and midbrain reticular formation (mRt).

Significant volume reductions were observed in the SCP (p < .001, Hedges’ g = 3.31) and MCP (p < .001, Hedges’ g = 1.77), alongside decreased fractional anisotropy (FA) in the MCP, indicative of impaired white matter integrity. FA_Avg fractional anisotropy average tested by FreeSurfer Tracula, is an index of white matter integrity, reflecting axonal fiber density, axonal diameter and myelination. These neuroimaging findings correlated with clinical manifestations of motor incoordination, proprioceptive deficits, and autonomic instability. Furthermore, volume loss in the dorsal raphe (DR) and midbrain reticular formation suggests disruption of pain modulation and sleep-wake cycles, consistent with patient-reported symptoms.

Post-mortem studies provide supporting evidence for brainstem involvement in COVID-19. Radtke et al. (2024) reported activation of intracellular signaling pathways and release of immune mediators in brainstem regions of deceased COVID-19 patients, suggesting an attempt to inhibit viral spread. While viral genetic material was detectable, infected neurons were not observed. Matschke et al. (2020) found that microglial activation and cytotoxic T lymphocyte infiltration were predominantly localized to the brainstem and cerebellum, with limited involvement of the frontal lobe. This aligns with clinical observations implicating the brainstem in PCS pathophysiology. Cell-specific expression analysis of genes contributing to viral entry (ACE2, TMPRSS2, TPCN2, TMPRSS4, NRP1, CTSL) in the cerebral cortex showed their presence in neurons, glial cells, and endothelial cells, indicating the potential for SARS-CoV-2 infection of these cell types. Associations with autoimmune diseases with specific autoantibodies, including beta-2 and M-2 against G-protein coupled alpha-1, beta-1, beta-2 adrenoceptors against angiotensin II type 1 receptor or M1,2,3-mAChR, among others, voltage-gated calcium channels (VGCC) are known (Blitshteyn et al. 2015 and Wallukat and Schminke et al. 2014).

These findings support the “Broken Bridge Syndrome” hypothesis, positing that structural disconnections between the brainstem and cerebellum contribute to PCS symptomatology. Furthermore, we propose that chronic activation of the Extended Autonomic System (EAS), encompassing the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system, may perpetuate these symptoms (Goldstein, 2020). Perturbations in this system may relate to the elevation of toxic autoantibodies AABs (Beta-2 and M-2), specific epitopes of the COVID virus’s SPIKE protein and Cytokine storm of IL-1, IL-6, and IL-8 in their increased numbers (1,000->10,000)

Further research is warranted to elucidate the underlying neuroinflammatory mechanisms, EAS dysregulation, and potential therapeutic interventions for PCS

Source: Ziaja Peter Christof, Young Yvette Susanne, Stark Sadre-Chirazi Michael, Lindner Thomas, Zurék Grzegorz, Sedlacik Jan. Brainstem Reduction and Deformation in the 4th Ventricle Cerebellar Peduncles in Long COVID Patients: Insights into Neuroinflammatory Sequelae and “Broken Bridge Syndrome” medRxiv 2025.04.08.25325108; doi: https://doi.org/10.1101/2025.04.08.25325108 https://www.medrxiv.org/content/10.1101/2025.04.08.25325108v1.full-text (Full text)

Direct effects of prolonged TNF-α and IL-6 exposure on neural activity in human iPSC-derived neuron-astrocyte co-cultures

Abstract:

Cognitive impairment is one of the many symptoms reported by individuals suffering from long-COVID and other post-viral infection disorders such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). A common factor among these conditions is a sustained immune response and increased levels of inflammatory cytokines. Tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) are two such cytokines that are elevated in patients diagnosed with long-COVID and ME/CFS.

In this study, we characterized the changes in neural functionality, secreted cytokine profiles, and gene expression in co-cultures of human iPSC-derived neurons and primary astrocytes in response to prolonged exposure to TNF-α and IL-6. We found that exposure to TNF-α produced both a concentration-independent and concentration-dependent response in neural activity.

Burst duration was significantly reduced within a few days of exposure regardless of concentration (1 pg/mL – 100 ng/mL) but returned to baseline after 7 days. Treatment with low concentrations of TNF-α (e.g., 1 and 25 pg/mL) did not lead to changes in the secreted cytokine profile or gene expression but still resulted in significant changes to electrophysiological features such as interspike interval and burst duration. Conversely, treatment with high concentrations of TNF-α (e.g., 10 and 100 ng/mL) led to reduced spiking activity, which may be correlated to changes in neural health, gene expression, and increases in inflammatory cytokine secretion (e.g., IL-1β, IL-4, and CXCL-10) that were observed at higher TNF-α concentrations.

Prolonged exposure to IL-6 led to changes in bursting features, with significant reduction in the number of spikes in bursts across a wide range of treatment concentrations (i.e., 1 pg/mL-10 ng/mL). In combination, the addition of IL-6 appears to counteract the changes to neural function induced by low concentrations of TNF-α, while at high concentrations of TNF-α the addition of IL-6 had little to no effect. Conversely, the changes to electrophysiological features induced by IL-6 were lost when the cultures were co-stimulated with TNF-α regardless of the concentration, suggesting that TNF-α may play a more pronounced role in altering neural function.

These results indicate that increased concentrations of key inflammatory cytokines associated with long-COVID can directly impact neural function and may be a component of the cognitive impairment associated with long-COVID and other post-viral infection disorders.

Source: Goshi N, Lam D, Bogguri C, George VK, Sebastian A, Cadena J, Leon NF, Hum NR, Weilhammer DR, Fischer NO, Enright HA. Direct effects of prolonged TNF-α and IL-6 exposure on neural activity in human iPSC-derived neuron-astrocyte co-cultures. Front Cell Neurosci. 2025 Feb 12;19:1512591. doi: 10.3389/fncel.2025.1512591. PMID: 40012566; PMCID: PMC11860967. https://pmc.ncbi.nlm.nih.gov/articles/PMC11860967/ (Full text)

Small fiber neuropathy in the post-COVID condition and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Clinical significance and diagnostic challenges

Abstract:

Background: Patients with post-COVID condition (PCC) and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) experience symptoms potentially associated with small fiber neuropathy (SFN).

Methods: A sample of 90 participants, comprising 30 PCC patients, 30 ME/CFS patients, and 30 healthy controls (HC), matched by sex and age, was assessed. Neuropathic, autonomic, and fatigue symptoms were measured with TaskForce Monitor, the Sudoscan, heat and cold evoked potentials, In Vivo Corneal Confocal Microscopy (IVCCM), and specialized questionaries.

Results: PCC and ME/CFS patients demonstrated significantly higher levels of autonomic symptoms (H = 39.89, p < 0.001), neuropathic symptoms (H = 48.94, p < 0.001), and fatigue (H = 49.29, p < 0.001) compared to HC. Quantitative sensory testing revealed significant differences in heat detection thresholds between PCC patients and HC (F = 4.82; p < 0.01). Regarding corneal small fiber tortuosity, there were statistically significant differences between patients and HC (F = 6.80; p < 0.01), indicating pathological responses in patients. Small fiber tortuosity in IVCCM was identified as the main discriminator between patients and HC (AUC = 0.720; p < 0.01).

Conclusion: PCC and ME/CFS patients demonstrated sensory SFN, as evidenced by impaired heat detection and increased tortuosity of small fibers in the central corneal subbasal plexus. The findings underscore the importance of a multimodal approach to comprehensively detect and characterize SFN. This study provides valuable scientific insights into the neuropathic manifestations associated with these conditions.

Source: Azcue N, Teijeira-Portas S, Tijero-Merino B, Acera M, Fernández-Valle T, Ayala U, Barrenechea M, Murueta-Goyena A, Lafuente JV, de Munain AL, Ruiz-Irastorza G, Martín-Iglesias D, Gabilondo I, Gómez-Esteban JC, Del Pino R. Small fiber neuropathy in the post-COVID condition and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Clinical significance and diagnostic challenges. Eur J Neurol. 2025 Feb;32(2):e70016. doi: 10.1111/ene.70016. PMID: 39888240. https://onlinelibrary.wiley.com/doi/10.1111/ene.70016 (Full text)

Effect of Immunoadsorption on clinical presentation and immune alterations in COVID-19-induced and/or aggravated ME/CFS

Abstract:

Autoreactive antibodies (AAB) are currently being investigated as causative or aggravating factors during post-COVID. In this study we analyze the effect of immunoadsorption therapy on symptom improvement and the relationship with immunological parameters in post-COVID patients exhibiting symptoms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) induced or aggravated by an SARS-CoV-2 infection. This observational study includes 12 post-COVID patients exhibiting a predominance of ME/CFS symptoms alongside increased concentrations of autonomic nervous system receptors (ANSR) autoantibodies and neurological impairments.

We found that following immunoadsorption therapy, the ANSR autoantibodies were nearly eliminated from the patients’ blood. The removal of IgG antibodies was accompanied by a decrease of pro-inflammatory cytokines including IL4, IL2, IL1β, TNF and IL17A serum levels, and a significant reduction of soluble spike protein. Notably, a strong positive correlation between pro-inflammatory cytokines and ASNR-AABs β1, β2, M3, and M4 was observed in spike protein-positive patients, whereas no such correlation was evident in spike protein-negative patients.

30 days post-immunoadsorption therapy, patients exhibited notable improvement in neuropsychological function and a modest but statistically significant amelioration of hand grip strength was observed. However, neither self-reported symptoms nor scores on ME/CFS questionnaires showed a significant improvement and a rebound of the removed proteins occurring within a month.

Source: Anft M, Wiemers L, Rosiewicz KS, Doevelaar A, Skrzypczyk S, Kurek J, Kaliszczyk S, Seidel M, Stervbo U, Seibert FS, Westhoff TH, Babel N. Effect of Immunoadsorption on clinical presentation and immune alterations in COVID-19-induced and/or aggravated ME/CFS. Mol Ther. 2025 Jan 9:S1525-0016(25)00011-5. doi: 10.1016/j.ymthe.2025.01.007. Epub ahead of print. PMID: 39797400. https://www.cell.com/molecular-therapy-family/molecular-therapy/pdf/S1525-0016(25)00011-5.pdf (Full text) https://pubmed.ncbi.nlm.nih.gov/39797400/ (Abstract)

Upregulation of olfactory receptors and neuronal-associated genes highlights complex immune and neuronal dysregulation in Long COVID patients

Abstract:

A substantial portion of patients infected with SARS-CoV-2 experience prolonged complications, known as Long COVID (LC). A subset of these patients exhibits the most debilitating symptoms, similar to those defined in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). We performed bulk RNA sequencing (RNAseq) on the whole blood of LC with ME/CFS, at least 12 months post-onset of the acute disease, and compared them with controls.

We found that LC patients had a distinct transcriptional profile compared to controls. Key findings include the upregulation of genes involved in immune dysregulation and neuronal development, such as Fezf2, BRINP2, HOXC12, MEIS2, ZFHX3, and RELN. These genes are linked to neuroinflammatory responses, cognitive impairments, and hematopoietic disturbances, suggesting ongoing neurological and immune disturbances in LC patients. RELN, encoding the Reelin protein, was notably elevated in LC patients, potentially serving as a biomarker for LC pathogenesis due to its role in inflammation and neuronal function.

Immune cell analysis showed altered profiles in LC patients, with increased activated memory CD4 + T cells and neutrophils, and decreased regulatory T cells and NK cells, reflecting immune dysregulation. Changes in cytokine and chemokine expression further underscore the chronic inflammatory state in LC patients. Notably, a unique upregulation of olfactory receptors (ORs) suggest alternative roles for ORs in non-olfactory tissues. Pathway analysis revealed upregulation in ribosomal RNA processing, amino acid metabolism, protein synthesis, cell proliferation, DNA repair, and mitochondrial pathways, indicating heightened metabolic and immune demands. Conversely, downregulated pathways, such as VEGF signaling and TP53 activity, point to impaired tissue repair and cellular stress responses.

Overall, our study underscores the complex interplay between immune and neuronal dysfunction in LC patients, providing insights into potential diagnostic biomarkers and therapeutic targets. Future research is needed to fully understand the roles and interactions of these genes in LC pathophysiology.

Source: Shahbaz S, Rezaeifar M, Syed H, Redmond D, Terveart JWC, Osman M, Elahi S. Upregulation of olfactory receptors and neuronal-associated genes highlights complex immune and neuronal dysregulation in Long COVID patients. Brain Behav Immun. 2024 Nov 28:S0889-1591(24)00721-9. doi: 10.1016/j.bbi.2024.11.032. Epub ahead of print. PMID: 39615603. https://www.sciencedirect.com/science/article/pii/S0889159124007219 (Full text)

Persistence of spike protein at the skull-meninges-brain axis may contribute to the neurological sequelae of COVID-19

Abstract:

SARS-CoV-2 infection is associated with long-lasting neurological symptoms, although the underlying mechanisms remain unclear. Using optical clearing and imaging, we observed the accumulation of SARS-CoV-2 spike protein in the skull-meninges-brain axis of human COVID-19 patients, persisting long after viral clearance. Further, biomarkers of neurodegeneration were elevated in the cerebrospinal fluid from long COVID patients, and proteomic analysis of human skull, meninges, and brain samples revealed dysregulated inflammatory pathways and neurodegeneration-associated changes.

Similar distribution patterns of the spike protein were observed in SARS-CoV-2-infected mice. Injection of spike protein alone was sufficient to induce neuroinflammation, proteome changes in the skull-meninges-brain axis, anxiety-like behavior, and exacerbated outcomes in mouse models of stroke and traumatic brain injury. Vaccination reduced but did not eliminate spike protein accumulation after infection in mice. Our findings suggest persistent spike protein at the brain borders may contribute to lasting neurological sequelae of COVID-19.

Source: Rong Z, Mai H, Ebert G, Kapoor S, Puelles VG, Czogalla J, Hu S, Su J, Prtvar D, Singh I, Schädler J, Delbridge C, Steinke H, Frenzel H, Schmidt K, Braun C, Bruch G, Ruf V, Ali M, Sühs KW, Nemati M, Hopfner F, Ulukaya S, Jeridi D, Mistretta D, Caliskan ÖS, Wettengel JM, Cherif F, Kolabas ZI, Molbay M, Horvath I, Zhao S, Krahmer N, Yildirim AÖ, Ussar S, Herms J, Huber TB, Tahirovic S, Schwarzmaier SM, Plesnila N, Höglinger G, Ondruschka B, Bechmann I, Protzer U, Elsner M, Bhatia HS, Hellal F, Ertürk A. Persistence of spike protein at the skull-meninges-brain axis may contribute to the neurological sequelae of COVID-19. Cell Host Microbe. 2024 Nov 26:S1931-3128(24)00438-4. doi: 10.1016/j.chom.2024.11.007. Epub ahead of print. PMID: 39615487. https://www.sciencedirect.com/science/article/pii/S1931312824004384 (Full text)