12/23/2025
One of the most telling signs of potential immune disruption from COVID-19 vaccines, particularly mRNA boosters, is the observed reactivation of the varicella-zoster virus (shingles).
The recent University of Groningen study in Drug Safety (analyzing over 2 million records) found a temporary increase in shingles risk post-vaccination:
• +7% overall within 28 days
• +21% after mRNA boosters
• Up to +38% in certain subgroups
Researchers point to a short-term decrease in immune surveillance, likely from transient lymphocyte depletion or reduced T-cell function—the very cells that keep the dormant virus in check. This allows the latent virus to reactivate.
Far from "overstimulation," the evidence leans toward transient immune suppression or modulation: temporary lymphopenia (low lymphocyte counts) and impaired VZV-specific T-cell immunity have been documented post-vaccination, mirroring effects seen in other vaccines or stressors that trigger shingles.
While some hypothesize TLR activation (innate immune stimulation) could play a role, the dominant explanation across studies is a brief window of weakened cell-mediated immunity—not hyperactivity—letting the virus escape latency.
This isn't just a minor rash for many: Severe shingles in older adults is linked to up to 7x higher dementia risk in separate research.
These findings highlight yet another concerning immune trade-off with repeated shots, where even small, transient disruptions can have outsized consequences.
🔗 Study: https://link.springer.com/article/10.1007/s40264-025-01638-2
🔗 Article: https://www.dailymail.co.uk/sciencetech/article-15396687/Covid-boosters-linked-virus-dementia.html