its in there Non-polio enterovirusis

Ah - so it's "related to polio" in the sense that it's specifically not polio? Sure, they fall into the same group, but they are not the same. Their "relation" does not mean that they will have the same effects or the same treatment/vaccination.

You can have Zika or West Nile. You can have leukemia or testicular cancer. There are differences.

I'm not quite sure what your point was about the "relation" between polio and meningitis. Are you comparing the effectiveness of treatment?