answered on 13 Nov 2019:
last edited 13 Nov 2019 9:43 pm
Nice question! We used to think absolutely not, however a group of scientists recently published some images of human brain tissue (postmortem) that showed bacteria in every living in various regions of the brain. They didn’t see any sign of inflammation or bacterial disease in these brains. This finding has also been shown in mice brains. They also studied the DNA of these bacteria. While this is super-intriguing, I would note that it is a really recent finding and it needs to be replicated by other groups and across the wide population before we take it as gospel.