Do Vaccines Trigger Neurological Diseases? Epidemiological Evaluation of Vaccination and Neurological Diseases Using Examples of Multiple Sclerosis, Guillain-Barré Syndrome and Narcolepsy

The risk of acute disseminated encephalomyelitis (ADEM) following covid-19 vaccination in England: A self-controlled case-series analysis

Acute disseminated encephalomyelitis (ADEM) has been identified as an Adverse Event of Special Interest in the COVID-19 vaccine programme due to its long-standing temporal association with a wide range of other vaccines. Case reports of ADEM shortly following COVID-19 vaccination have now been documented.    There were 217 ADEM admissions in 215 individuals in the period 8th December 2020 to 31st March 2023. An increased risk of ADEM following the first dose of ChAdOx1 vaccine was observed (relative incidence (RI) = 3.13, 95% Confidence Interval (CI) [1.56-6.25]) with a vaccine attributable risk of 0.39 per million doses. When doses 1 and 2 were combined this increased risk remained just significant (1.96 [95%CI 1.01-3.82]). No significant increased risk was observed with any other vaccine or dose. This small, elevated risk after the first dose of ChAdOx1-S vaccine demonstrates how large national electronic datasets can be used to identify very rare risks and provides reassurance that any risk of ADEM following the ChAdOx1-S COVID-19 vaccination is extremely small. Given the rarity of this risk, further studies in settings with access to data on large populations should be carried out to verify these findings.

Autoimmune/inflammatory syndrome induced by adjuvants (ASIA): past, present, and future implications

Adjuvants, as the name indicates, are adjoined material aimed to assist in functioning as when added to vaccines they are meant to boost the effect and strongly stimulate the immune system. The response of the immune system can be unpredictable, and the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) was developed to address possible adverse reactions of an autoimmune and inflammatory type that may be caused by adjuvants. While ASIA, as a syndrome, was coined and defined in 2011; reports describing patients with vague and nonspecific clinical symptoms following vaccinations appeared much earlier. In other words, ASIA came to define, arrange, and unite the variety of symptoms, related to autoimmunity, caused not by the vaccine itself, rather by the adjuvant part of the vaccine such as aluminum, among others. Accordingly, the introduction of ASIA enabled better understanding, proper diagnosis, and early treatment of the disorder. Furthermore, ASIA was shown to be associated with almost all body systems and various rheumatic and autoimmune diseases such as systemic lupus erythematosus, antiphospholipid syndrome, and systemic sclerosis. In addition, the correlation between COVID-19 and ASIA was noticed during the pandemic. In this review, we summarized the reported effects of adjuvants and medical literature before and after ASIA was defined, the several ways ASIA can manifest and impact different systems of the body, and the incidences of ASIA during the COVID-19 pandemic. It is important to clarify, that vaccines are among, if not the, most effective means of fighting infectious diseases however, we believe that vaccines manufacturing is not above criticism, particularly when it comes to added substances possessing a risk of side effects.

Controversies in neuroimmunology: multiple sclerosis, vaccination, SARS-CoV-2 and other dilemas

Neuroimmunology is a discipline that increasingly broadens its horizons in the understanding of neurological diseases. At the same time, and in front of the pathophysiological links of neurological diseases and immunology, specific diagnostic and therapeutic approaches have been proposed. Despite the important advances in this discipline, there are multiple dilemmas that concern and filter into clinical practice. This article presents 15 controversies and a discussion about them, which are built with the most up-to-date evidence available. The topics included in this review are: steroid decline in relapses of multiple sclerosis; therapeutic recommendations in MS in light of the SARS-CoV-2 pandemic; evidence of vaccination in multiple sclerosis and other demyelinating diseases; overview current situation of isolated clinical and radiological syndrome; therapeutic failure in multiple sclerosis, as well as criteria for suspension of disease-modifying therapies; evidence of the management of mild relapses in multiple sclerosis; recommendations for prophylaxis against Strongyloides stercolaris; usefulness of a second course of immunoglobulin in the Guillain-Barré syndrome; criteria to differentiate an acute-onset inflammatory demyelinating chronic polyneuropathy versus Guillain-Barré syndrome; and, the utility of angiotensin-converting enzyme in neurosarcoidosis. In each of the controversies, the general problem is presented, and specific recommendations are offered that can be adopted in daily clinical practice.

Reducing infection risk in multiple sclerosis and neuromyelitis optica spectrum disorders: a Brazilian reference center's approach

BACKGROUND

Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are the most common autoimmune diseases of the central nervous system (CNS). They present chronic relapsing courses that demand treatment with disease-modifying drugs (DMDs) to prevent inflammatory activity. Disease-modifying drugs lead to immunomodulation or immunosuppression through diverse mechanisms (e.g., shifting lymphocyte and cytokine profile, suppressing specific lymphocyte subpopulations). Thus, patients are more prone to infectious complications and associated worsening of disease.

OBJECTIVE

To present feasible strategies for mitigating the infection risk of MS and NMOSD treated patients.

METHODS

Targeted literature review concerning the management of infection risk with an emphasis on vaccination, therapy-specific measures, and particularities of the Brazilian endemic infectious diseases' scenario.

CONCLUSION

We propose a vaccination schedule, infectious screening routine, and prophylactic measures based on the current scientific evidence. Awareness of emergent tropical diseases is necessary due to evidence of demyelinating events and possible parainfectious cases of MS and NMOSD.

Guillain-Barré syndrome following SARS-CoV-2 vaccination in the UK: a prospective surveillance study

Objective

To investigate features of Guillain-Barré syndrome (GBS) following SARS-CoV-2 vaccines and evaluate for a causal link between the two.

Methods

We captured cases of GBS after SARS-CoV-2 vaccination through a national, open-access, online surveillance system. For each case, the certainty of GBS was graded using the Brighton criteria, and the relationship to the vaccine was examined using modified WHO Causality Assessment criteria. We compared age distribution of cases with that of prepandemic GBS cases and clinical features with the International GBS Outcome Study (IGOS).

Results

Between 1 January and 30 June 2021, we received 67 reports of GBS following the ChAdOx1 vaccine (65 first doses) and three reports following the BNT162b2 vaccine (all first doses). The causal association with the vaccine was classified as probable for 56 (80%, all ChAdOx1), possible for 12 (17%, 10 ChAdOx1) and unlikely for two (3%, 1 ChAdOx1). A greater proportion of cases occurred in the 50–59 age group in comparison with prepandemic GBS. Most common clinical variants were sensorimotor GBS (n=55; 79%) and facial diplegia with paraesthesias (n=10; 14%). 10% (n=7/69) of patients reported an antecedent infection, compared with 77% (n=502/652) of the IGOS cohort (p<0.00001). Facial weakness (63% (n=44/70) vs 36% (n=220/620); p<0.00001) and sensory dysfunction (93% (n=63/68) vs 69% (n=408/588); p=0.00005) were more common but disease severity and outcomes were similar to the IGOS study.

Interpretation

Most reports of GBS followed the first dose of ChAdOx1 vaccine. While our study cannot confirm or refute causation, this observation, together with the absence of alternative aetiologies, different than expected age distribution and the presence of unusual clinical features support a causal link. Clinicians and surveillance bodies should remain vigilant to the possibility of this very rare adverse event and its atypical variants.

Guillain-Barré Syndrome Associated with COVID-19 Vaccines: A Perspective From Spontaneous Report Data

BACKGROUND AND OBJECTIVE

The concern surrounding the association between Guillain-Barré syndrome (GBS) and vaccination has increased with the widespread use of COVID-19 vaccines. The aim of this study was to assess the potential association of GBS with mRNA-based or adenovirus-vectored COVID-19 vaccines.

METHODS

Reports of GBS associated with mRNA-based or adenovirus-vectored COVID-19 vaccines were extracted from the WHO pharmacovigilance database, exposure data from the Our World in Data website, and the background rates of GBS from published data. For countries contributing to VigiBase and with available data on COVID-19 vaccine exposure, reporting rates were estimated and observed-to-expected (OE) analyses were performed.

RESULTS

A total of 2499 cases were included: 1157 (46.3%) cases with adenovirus-vectored COVID-19 vaccines and 1342 (53.7%) with mRNA-based COVID-19 vaccines. The male-to-female sex ratio was 1.09 and the median (IQR) age was 57 (45-66) years. The reporting rates (95% CI) per 100,000 person-years within the 42-day window were 5.57 (5.13-6.03) for adenovirus-vectored COVID-19 vaccines and 1.39 (1.31-1.47) for mRNA-based COVID-19 vaccines, while the background incidence was 1.2-3.1 per 100,000 person-years. For mRNA-based COVID-19 vaccines, the OE ratio was <1 for both time windows in all European countries and slightly elevated for the 21-day window in the USA. For adenovirus-vectored COVID-19 vaccines, the OE ratio was consistently > 2.0 for all countries. Sensitivity analyses minimally altered these results.

CONCLUSIONS

These findings suggest both the absence of safety concern for GBS with mRNA-based COVID-19 vaccines and an increased risk with adenovirus-vectored COVID-19 vaccines. Back to top.

Vaccination and immunotherapies in neuroimmunological diseases

Neuroimmunological diseases and their treatment compromise the immune system, thereby increasing the risk of infections and serious illness. Consequently, vaccinations to protect against infections are an important part of the clinical management of these diseases. However, the wide variety of immunotherapies that are currently used to treat neuroimmunological disease — particularly multiple sclerosis and neuromyelitis optica spectrum disorders — can also impair immunological responses to vaccinations. In this Review, we discuss what is known about the effects of various immunotherapies on immunological responses to vaccines and what these effects mean for the safe and effective use of vaccines in patients with a neuroimmunological disease. The success of vaccination in patients receiving immunotherapy largely depends on the specific mode of action of the immunotherapy. To minimize the risk of infection when using immunotherapy, assessment of immune status and exclusion of underlying chronic infections before initiation of therapy are essential. Selection of the required vaccinations and leaving appropriate time intervals between vaccination and administration of immunotherapy can help to safeguard patients. We also discuss the rapidly evolving knowledge of how immunotherapies affect responses to SARS-CoV-2 vaccines and how these effects should influence the management of patients on these therapies during the COVID-19 pandemic.

In this Review, the authors discuss how various immunotherapies for neuroimmunological diseases interact with vaccination responses, including responses to SARS-CoV-2 vaccinations, and the implications for the safe and effective use of vaccines in patients with these diseases.

Vaccination against infection is an essential part of the management of neuroimmunological diseases.

All indicated vaccinations should be administered before initiation of immunotherapy whenever possible; appropriate intervals between vaccination and treatment vary with treatment and vaccination.

Inactivated vaccines are considered safe in neuroimmunological diseases but live vaccines are generally contraindicated during immunotherapy.

Vaccination responses during immunotherapy can be diminished or abrogated, depending on the treatment and vaccination; antibody titre testing to monitor responses can be considered where appropriate.

Vaccinations must be avoided during relapses or exacerbations of neuroimmunological diseases.

Vaccination against SARS-CoV-2 is recommended for patients with neuroimmunological disease but some immunotherapies limit the immune response; therefore, timing should be considered carefully.

Vaccination in pediatric acquired inflammatory immune-mediated neuromuscular disorders

AIM

To analyse literature data on vaccine related induction, worsening of the disease and disease reccurrences as well as vaccine safety and efficacy among pediatric patients with acquired inflammatory immune-mediated neuromuscular disorders (NMD).

METHODS

Medline, Pub Med and Scopus database search from 1975 to 2020 focused on pediatric age was conducted including peer reviews, meta analyses and epidemiological studies on vaccination and Guillain-Barré syndrome (GBS), Bell's palsy, optic neuritis (ON), myasthenia gravis (MG), chronic inflammatory demyelinating polyneuropathy (CIDP) and immune-mediated inflammatory myopathy (IM).

RESULTS AND CONCLUSION

s: There are no strong evidence supporting relationship between vaccination with different pediatric vaccines and development of first episodes or reccurrences of GBS, Bell's palsy, optic neuritis (ON), juvenile MG, CIDP, and IM. The vaccination and revaccination with inactivated vaccines is considered safe in children with medical history of GBS, Bell's palsy, ON, MG and IM. Caution when immunization against influenza, quadrivalent conjugated meningococcal vaccine (MCV4) and pneumococcal disease and avoiding tetanus toxoid immunization in CIDP patients is suggested. Patients with immune mediated acquired NMD should be vaccinated with live vaccines before the initiation of immunosupressive treatment. Immunosuppressed patients with low protective antibody titers should be considered for revaccination.

COVID-19 pandemic effects in people with Autism Spectrum Disorder and their caregivers: Evaluation of social distancing and lockdown impact on mental health and general status

Among the difficulties associated with Autism Spectrum Disorder (ASD) are those related to adaptation to changes and new situations, as well as anxious-depressive symptoms frequently related to excessive environmental requirements. The main objective of this research is to study the psychological impact of the lockdown due to the social emergency situation (COVID-19) in children/adolescents and adults diagnosed with ASD. Participants were 37 caregivers of children/adolescents with ASD, also 35 ASD adults and 32 informants. Evaluation was conducted through a web survey system and included standardized clinical questionnaires (CBCL and SCL-90-R), which were compared with results before lockdown start, and a brief self-reported survey addressing the subjective perception of changes in daily functioning areas. The results revealed a reduction of psychopathological symptoms in both age groups, but only reaching statistical significance in the adult group, except for Somatization, Anxiety, and Obsessive-Compulsive domains. ASD severity Level 2 showed greater improvement after lockdown onset in the children/adolescent group when compared to ASD Level 1 participants. Younger adults (18-25 yoa) reported greater improvement than older adults (=>25 yoa). Survey results indicate an improvement of feeding quality and a reduction in the number of social initiations during the lockdown. Adult ASD participants perceived a decrease in stress levels after the lockdown onset, whereas caregivers reported higher stress levels at the same point in both age groups. Limitations included the small number of participants and a heterogeneous evaluation window between measures. Pyschopathological status after two months of social distancing and lockdown seems to improve in ASD young adult population.

Association between cervical disc disease and lesions of multiple sclerosis

BACKGROUND

Cervical discopathy and demyelinating lesions often co-exist in patients with multiple sclerosis (MS). Our study examines the possible association between these two pathologies.

METHODS

Medical records and cervical magnetic resonance imaging scans of MS patients with cervical discopathy who were seen at our MS clinic during 2018 were retrospectively reviewed. The severity of the disc disease was classified as grade I (no compression), grade II (compression of the dural sac) and grade III (cord compression). The spinal cord in each scan was divided into six segments corresponding to the intervertebral space of the spine (C1-C6). Each segment was defined as containing demyelinating lesion and disc pathology (group 1), demyelinating lesion without disc pathology (group 2), disc pathology without demyelinating lesion (group 3) and no demyelinating lesion or disc pathology (group 4). Fisher's exact test was used to test the association between demyelinating lesions and disc pathology.

RESULTS

Thirty-four MS patients with cervical discopathy were included in the study (26 females; average age 42.9 ± 13.7 years; average disease duration 8.4 ± 5.4 years). A total of 204 spinal cord segments were evaluated. Twenty-four segments were classified as group 1, 27 segments as group 2, 52 segments as group 3 and 101 segments as group 4. There was no association between demyelinating lesions and the grade of disc disease (p = 0.1 for grade I, p = 0.3 for grade II and p = 1 for grade III disc disease).

CONCLUSION

Our study did not find any association between cervical disc disease and demyelinating spinal cord lesion.

Reassessment of the risk of narcolepsy in children in England 8 years after receipt of the AS03-adjuvanted H1N1 pandemic vaccine: A case-coverage study

BACKGROUND

Early studies of narcolepsy after AS03-adjuvanted pandemic A/H1N12009 vaccine (Pandemrix) could not define the duration of elevated risk post-vaccination nor the risk in children aged under 5 years who may not present until much older.

METHODS/FINDINGS

Clinical information and sleep test results, extracted from hospital notes at 3 large pediatric sleep centers in England between September 2017 and June 2018 for narcolepsy cases aged 4-19 years with symptom onset since January 2009, were reviewed by an expert panel to confirm the diagnosis. Vaccination histories were independently obtained from general practitioners (GPs). The odds of vaccination in narcolepsy cases compared with the age-matched English population was calculated after adjustment for clinical conditions that were indications for vaccination. GP questionnaires were returned for 242 of the 244 children with confirmed narcolepsy. Of these 5 were under 5 years, 118 were 5-11 years, and 119 were 12-19 years old at diagnosis; 39 were vaccinated with Pandemrix before onset. The odds ratio (OR) for onset at any time after vaccination was 1.94 (95% confidence interval [CI] 1.30-2.89), The elevated risk period was restricted to onsets within 12 months of vaccination (OR 6.65 [3.44-12.85]) and was highest within the first 6 months. After one year, ORs were not significantly different from 1 up to 8 years after vaccination. The ORs were similar in under five-year-olds and older ages. The estimated attributable risk was 1 in 34,500 doses. Our study is limited by including cases from only 3 sleep centers, who may differ from cases diagnosed in nonparticipating centers, and by imprecision in defining the centers' catchment population. The potential for biased recall of onset shortly after vaccination in cases aware of the association cannot be excluded.

CONCLUSIONS

In this study, we found that vaccine-attributable cases have onset of narcolepsy within 12 months of Pandemrix vaccination. The attributable risk is higher than previously estimated in England because of identification of vaccine-attributable cases with late diagnoses. Absence of a compensatory drop in risk 1-8 years after vaccination suggests that Pandemrix does not trigger onsets in those in whom narcolepsy would have occurred later.

[Recommendations on the approach when unusual neurological symptoms occur in temporal association with vaccinations in childhood and adolescence]

Vaccinations are often administered at an age when many neurological diseases of childhood and adolescence also occur. Febrile seizures may occur following vaccination in patients with an appropriate genetic predisposition. The occurrence of narcolepsy has been described more frequently after pandemic influenza A-H1N1 vaccinations. The causality has not been proven. Data regarding an association between Guillain-Barré syndrome and influenza vaccinations are inconclusive. It was conclusively shown that vaccinations do not cause neurological disorders, such as autism and do not trigger multiple sclerosis. In summary, there is currently no confirmed evidence for the occurrence of chronic neurological diseases as a consequence of generally recommended vaccinations in Germany. If unusual neurological symptoms are observed in temporal association with vaccinations, a comprehensive evaluation is necessary to exclude a causal relationship and to diagnose the underlying neurological disease independent of the vaccination. This statement gives specific recommendations for the practical approach when neurological symptoms are observed in temporal association with vaccinations with respect to taking the patient history, initial diagnostic procedures, accurate and prompt documentation and the obligation to report the event. The committee also proposes procedures for further clarification and differential diagnostics of causal neurological diseases in childhood and adolescence.