What role does your gut microbiome (the sum of bacterial species living in your gut) play in your body’s immune response to vaccines? I address this question here:
I don’t go into a lot of detail, but it’s clear that the gut microbiome plays a role, and if I had to speculate about rare, adverse events, I’d speculate that they may be caused in part by your body’s past responses/ current overload or under-stimulation by the specific species of bacteria in your gut. Other factors will play a role too- like genetics- but I really do think your gut microbiome will play a significant part.
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