SARS-CoV-2 Vaccination and Neuroimmunological Disease: A Review.

Importance: The temporal association between the occurrence of neurological diseases, many autoimmune diseases, and vaccination against SARS-CoV-2 has been topically interesting and remains hotly debated both in the medical literature and the clinic. Given the very low incidences of these events both naturally occurring and in relation to vaccination, it is challenging to determine with certainty whether there is any causative association and most certainly what the pathophysiology of that causation could be. Observations: Data from international cohorts including millions of vaccinated individuals suggest that there is a probable association between the adenovirus-vectored vaccines and Guillain-Barré syndrome (GBS). Further associations between other SARS-CoV-2 vaccines and GBS or Bell palsy have not been clearly demonstrated in large cohort studies, but the possible rare occurrence of Bell palsy following messenger RNA vaccination is a topic of interest. It is also yet to be clearly demonstrated that any other neurological diseases, such as central nervous system demyelinating disease or myasthenia gravis, have any causative association with vaccination against SARS-CoV-2 using any vaccine type, although it is possible that vaccination may rarely trigger a relapse or worsen symptoms or first presentation in already-diagnosed or susceptible individuals. Conclusions and Relevance: The associated risk between SARS-CoV-2 vaccination and GBS, and possibly Bell palsy, is slight, and this should not change the recommendation for individuals to be vaccinated. The same advice should be given to those with preexisting neurological autoimmune disease.

Zika virus infection in the returning traveller: what every neurologist should know.

Zika virus has been associated with a wide range of neurological complications. Neurologists in areas without current active transmission of the virus may be confronted with Zika-associated neurological disease, as a large number of returning travellers with Zika virus infection have been reported and the virus continues to spread to previously unaffected regions. This review provides an overview of Zika virus-associated neurological disease and aims to support neurologists who may encounter patients returning from endemic areas.