How concerned should I be about prions and their related illnesses?

I have OCD, and prions completely terrify me. So much so that I stopped eating beef years ago and more recently have stopped eating all meat + fish and eggs (along with most other foods). Rapidly losing weight. Most days I just eat whatever doesn't feel contaminated.

It's difficult for me to know how much of this fear is irrational and how much of it may be rooted in reality.

Why do we not see more prion illnesses? How has there not been a massive epidemic/pandemic?

My understanding is limited. I'm not a scientist. I've only read what I can find on the internet. I would like to know more and have a discussion.

On the OCD front, I've tried almost every available treatment, except ketamine and deep brain stimulation. Already signed up to give ketamine a go.