Yeah they really are scary dangerous. The risk of exposure is low. There are some other important transmission channels to consider. As you noted on their temperature stability, prions aren't sterilized by normal medical sterilization procedures including autoclaving. So transmission of prions by surgical instruments can occur and is well documented. The conventional advice is that surgical instruments contaminated with prions need to be thrown out. It can also occur with organ transplants. Advice: don't read about this if you're scheduled for surgery. It's probably the smallest risk you'll encounter but it might really capture your imagination.
As noted in the article, prions are also responsible for 'mad cow disease', Bovine Spongiform Encephalopathy (BSE) as well as Creutzfeldt–Jakob disease. If you really want to get into prions you can start with the wikipedia entries for those. They're pretty incredible from a physics / biology standpoint.
The thing the article doesn't point out that is important to keep in mind is that CJD is a really awful neurological wasting disease and it's likely that in those seven years Émilie Jaumain and her family suffered terribly.