COVID-19 vaccines have been instrumental in reducing the impact of the pandemic, but some individuals have reported chronic symptoms that developed soon after receiving a COVID-19 vaccine. This condition, referred to as post-vaccination syndrome (PVS), is little understood and requires further research.
A new study by Yale researchers has taken initial steps to characterize PVS, uncovering potential immunological patterns that differentiate those with PVS from others. The findings suggest that individuals with PVS may have lower levels of certain immune cells and different antibody responses to the SARS-CoV-2 spike protein.
The most common symptoms of PVS include exercise intolerance, excessive fatigue, brain fog, insomnia, and dizziness, which can develop shortly after vaccination and persist over time. The study’s findings are early and require further confirmation but may eventually guide strategies to help affected individuals.
Researchers believe that PVS might be similar to how different infections can cause chronic symptoms through distinct biological pathways. They are now investigating several possible drivers of PVS, including autoimmunity, tissue damage, and Epstein-Barr Virus (EBV) reactivation.
The study’s authors emphasize the need for further research to understand PVS and its drivers. “We’re only just starting to make headway in understanding PVS,” said Harlan Krumholz, co-senior author of the study. “Every medical intervention carries some risk, and it’s essential to acknowledge that adverse events can occur with vaccines.”
Source: https://news.yale.edu/2025/02/19/immune-markers-post-vaccination-syndrome-indicate-future-research-directions