Tornados are not wide, area-effect disasters. They're forgiving in that regard: preferring a relatively narrow swath of absolute destruction.

The 2013 Moore, OK tornado was 1.08 miles (1.74 km) wide at its peak.

https://en.wikipedia.org/wiki/2013_Moore_tornado

That's nowhere near the widest, just the widest F5 that comes to mind. 11 days later the widest tornado on record struck on the other side of the OKC metro, and would've been an F5 in a populated area:

Officially, the widest tornado on record is the El Reno, Oklahoma tornado of May 31, 2013 with a width of 2.6 miles (4.2 km) at its peak. This is the width found by the National Weather Service based on preliminary data from University of Oklahoma RaXPol mobile radar that also sampled winds of 296 mph (476 km/h) which was used to upgrade the tornado to EF5

https://en.wikipedia.org/wiki/Tornado_records

Disease, war, or as the article suggests ecological devastation are more likely.

A tornado with a particular placement could be a precursor to all of these things. Missouri has had some of the deadliest tornado's on record. Supporting thousands of people requires a lot of food, and if a sizeable portion of your crop is destroyed by a major weather event, people have to leave town.