Syncopes, paresis and loss of vision after COVID-19 mRNA-based vaccination and SARS-CoV-2 infection.

mRNA-based vaccines played a key role in fighting the global COVID-19 pandemic by saving millions of lives. In rare cases, however, the BNT162b2 vaccine has been associated with severe adverse reactions e.g. myocarditis (OE ratio 2.78; 95% CI 2.61; 2.95) [Faksova in Vaccine 42(9):2200-2211, 2024, https://doi.org/10.1016/j.vaccine.2024.01.100 , Schwab in Clin Res Cardiol 112(3):431-440, 2022, https://doi.org/10.1007/s00392-022-02129-5 ]. Here, we describe the case of a 38-year-old man who developed a wide variety of long-term symptoms (fatigue, dizziness, palpitations with recurrent syncopes, paresthesia, paresis and fasciculations) following his first mRNA-based BNT162b2 COVID-19 vaccination. 143 days after vaccination, a subsequent COVID-19 infection was associated with exacerbation of paresis and a temporary loss of vision. After ruling out other causes and due to the immediate temporal association, an adverse reaction to vaccination appears likely. The fact that these symptoms worsened after a subsequent acute COVID 19 infection hints at the possibility of a common underlying pathophysiology. This case combines two clinical phenomena that have emerged during the COVID 19 pandemic, side effects associated with novel vaccines and Post-COVID Syndrome.