It’s talked about in terms of Long COVID and whether or not it’s psychosomatic, the policies made during the lockdowns, and so forth, but always with so much emotion, and sometimes for good reason. I don’t want to dismiss that or trivialize it. Those are important topics to discuss for how we’ll handle future pandemics.
But the evidence is accumulating that COVID does seem to impact CD8+ T cells, causing T cell exhaustion and reduced effector response. One running hypothesis is that the impaired immune response is caused by a persistent viral reservoir infection, particularly in the gut (although not all people show signs of a spike protein months after the initial infection) causing your CD8+ T cells to express more inhibitory receptors (similar to what happens in HIV or cancer with excessive and prolonged exposure to cancer cells).
Another hypothesis that is lesser known but I find particularly compelling is gut dysbiosis following a COVID infection causing a persistent immune activation that leads to T cell exhaustion or impaired T cell functionality especially through persistent activation of the dendritic cells (which are important for presenting antigens to the adaptive immune systems (i.e. T cells, B cells, etc)).
I think a researcher put it best when they said COVID is roughly halfway between HIV and the common cold in terms of the impact it has on the immune system. It may also not be accurate. We have to find out.
For context, think about how long it took to realize the Epstein Barr virus was a causal factor in multiple sclerosis. It took years of evidence collecting and data analysis to eliminate other confounding variables.
We shouldn’t rush to judgement or a narrative, but remain calm and dispassionate here and examine what’s going on, both for the virus, the vaccine, and the actions taken during the pandemic. It’s important we get it right.