Part of it is the various government agencies are becoming much better at finding various disease-causing bugs.
Here’s a WaPo article on the subject:
https://www.washingtonpost.com/national/health-science/what-you-need-to-know-about-food-recalls/2018/07/13/4fbd294e-74b8-11e8-805c-4b67019fcfe4_story.html?noredirect=on&utm_term=.ff6738bebecf
Very informative. Thanks. :D