Can you just explain for us what is P. gingivalis?

Parpheromonas gingivalis is the full name, and I'll usually refer to it as P. gingivalis or just PG.

It's a bacteria, you know, you've heard of streptococcus bacteria, pneumococcus, and other bacteria like that.

It's a bacterium that gets into your body.

It is best known for being found in the mouth and for being associated with gum disease, not the teeth, but the gums.

And the mild form of that is called gingivitis.

And when it gets more severe, it's called periodontal disease or periodontitis.

So Deborah from Santa Barbara, California asked, how does the bacteria in your mouth get past the blood-brain barrier?