I wonder if SUVs can be plausibly blamed for this

Pantagraph.com | News | Illinois once 'emporium' of malaria

“When I first settled in Peoria some thirty-five years ago (about 1848) the entire prairie was saturated with malaria,” wrote Dr. J. Murphy in 1883. “In fact, the entire area of central Illinois was a gigantic emporium of malaria.”