I’m skeptical but there’s plenty of intracellular bacterial pathogens. Perhaps there’s an intracellular commensal bacteria/symbiote. I think if it was extracel

I’m skeptical but there’s plenty of intracellular bacterial pathogens. Perhaps there’s an intracellular commensal bacteria/symbiote. I think if it was extracellular we would see it more often in CSF - which is collected quite a bit in healthcare. Regular histology/pathology slices and staining would detect as well. I could imagine an intracellular commensal bacteria that is small and virtually indistinguishable from an organelle like a mitochondria or lysosome that may exist. Mitochondria were already bacteria at one point. Could there be another endosymbiont? Mitochondria have circular DNA and phage like polymerase. Perhaps our secret symbiont can be found through DNA studies. Examples of intracellular bacterial pathogens include: Brucella abortus Listeria spp. Chlamydia spp. Rickettsia spp. Ehrlichia spp. Anaplasma spp. Coxiella spp. Mycobacterium tuberculosis Salmonella spp.