Covid-19 vaccines and neurological complications: a systematic review

The COVID-19 mainly causes respiratory disorders with high infection and severe morbidity and mortality. Neurologists have concerns about potential neurological side effects, profits, and timing of COVID-19 vaccines. This study aimed to review systematically research for the COVID-19 vaccine and neurological complications. Data was searched in Scopus, ISI web of knowledge, Medline, PubMed, Wiley, Embase, International Clinical Trials Registry Platform and Clinical Trials, Cochrane Library, and Google Scholar. Two reviewer authors individually searched and assessed the titles and abstracts of all articles. The third reviewer resolved disagreement between them. Data were documented regarding study location, study design, type of complications, number of patients, various types of COVID-19 vaccine, and type of neurological complications. Six studies in COVID-19 vaccine and neurological complications include two studies about neurological manifestations after the mRNA vaccines, four records about side effects of vector-based vaccine were included in the study. The main neurological complication associated mRNA vaccines were body aches, paresthesia, and difficulty walking, erythema migrans lesion, fatigue, myalgia, and pain in the left lateral deltoid region. The major neurological complication related to vector-based vaccines were urinary retention difficulty, feeding and ambulating, arm soreness, mild fatigue, chills, left-sided facial droop, headaches, a generalized epileptic seizure, hemianopia, and mild aphasia, acute somnolence and right-hand hemiparesis, acute transverse myelitis, deep vein thrombosis in her left leg, a vigilance disorder and a twitching, a severe immobilizing opsoclonus myoclonus syndrome, and encephalitis. A large spectrum of severe neurological unfavorable has been reported. These complications could occur as a result of molecular stimulation and later neuronal damage. Generally, the advantages of COVID-19 vaccination are dominant on the risks of a neurological complication at both individual and population levels. Future investigations will be required to find any relationship between neurological complications and COVID-19 vaccines principally as new strains of the virus and new vaccines are technologically advanced against them.