Are the bugs are getting smarter?...

Nope - we're just committing the same unforced errors as usual.

Peanut butter happens to be a pretty safe food when it comes to microorganisms. That's because the nuts are blanched, roasted, and ground up at temperatures high enough to kill any salmonella bacteria that might have gotten into the raw ingredients. But the germs can still contaminate the product in the "post-processing" phase of production—when the finished product is loaded into jars and labeled for sale. The only other known outbreak of peanut butter-related salmonellosis occurred in Australia in the mid-1990s: Post-processing contamination with fecal matter was the likely culprit.

More of a very helpful explanation of what is going on in those jars. Not to trivialize, but 300 people getting sick implies a 1 in a million chance. Thanks to modern communication outbreaks terminate quickly and while no picnic for the victims, fatalities are rare.

Or in this case, non-existent to date.

(Wait - there may be one).