# A comparison of Gam-COVID-Vac vaccination and non-vaccination on neurological symptoms and immune response in post-COVID-19 syndrome

## TL;DR

This study found that the Gam-COVID-Vac vaccine reduces neurological symptoms in long COVID-19 patients, particularly in the central nervous system.

## Contribution

The study provides new evidence that vaccination can alleviate specific neurological symptoms in post-COVID-19 syndrome.

## Key findings

- Gam-COVID-Vac vaccination significantly reduced headaches, sleep disturbances, and dizziness in long COVID-19 patients.
- Vaccinated patients showed higher B-lymphocyte counts compared to non-vaccinated individuals.
- Humoral immunity was strong in both groups, but T-cell and NK cell levels showed no significant changes.

## Abstract

The post-COVID-19 syndrome may present with a range of neurological symptoms such as headaches, sleep disorders, and dizziness. The objective of this study was to examine the effectiveness of the Gam-COVID-Vac vaccine in mitigating the neurological symptoms of post-COVID-19 syndrome. The study involved 95 patients diagnosed with the neurological form of long COVID-19, who were divided into two groups according to their vaccination status. The immunological parameters of humoral immunity were evaluated by enzyme-linked immunosorbent assay (ELISA), while the parameters of cellular immunity were evaluated using flow cytometry. Administration of the vaccination resulted in a reduction in clinical symptoms of the neurological form of long COVID-19. Statistically significant differences (p = 0.035) were found in symptoms such as headaches, sleep disturbances, and dizziness, especially in central nervous system (CNS) disorders, between the groups that received the vaccination and those that did not. More than 90% of patients had elevated levels of Receptor Binding Domain (RBD) immunoglobulin G against the viral S-protein (>2,500 BAU/ml), indicating strong humoral immunity regardless of vaccination status. An increase in B-lymphocyte (CD3-CD19+) counts was noted in both groups, with levels significantly higher in the group that received the vaccination (p < 0.03). Analysis of T-cell profiles and NK (natural killer) cell levels showed no changes. The study suggests that administration of Gam-COVID-Vac vaccination could reduce the occurrence of CNS symptoms in individuals with post-COVID-19 syndrome. Although certain neurological symptoms may continue, immunization has a beneficial influence on their progression. The results emphasize the crucial role of an increased humoral immune response in individuals with post-COVID-19 syndrome, but do not show significant changes in T-cell immune parameters.