This happened to my Mom a few years ago in New Mexico. She was late 70s and immuno-compromised from cancer treatments. She ended up hospitalized on a ventilator due to meningitis resulting from the Listeria infection. She made it out OK, but it was very serious.
Best theory the Health Department had that it was from unpasteurized cheese.
—In 2013, the median age of burners was 32, and in 2022, it was 37.
My take away was that it seems like it is the same people going every year: they are getting older and richer, because that is what happens over time.