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Fleas, lice, mosquitoes, pretty nearly all of the creatures of Pandora's box and diseases which nobody has seen in the US in many decades including malaria, typhus and plague...
There is exactly one thing which can eliminate the worst dangers from this situation and that is the most politically incorrect thing in the entire world of better living through chemistry i.e. DDT. DDT needs to be re-legalized immediately.
Granted using DDT as a large-scale area pesticide for crops was problematical, using it to protect human habitat areas had no downside. DDT remains a legitimate candidate for greatest thing Western man ever invented and, basically, the claims we started reading from Rachel Carson and others in the early 70s have been debunked. The stuff was absolute death on the creatures of Pandora's box and had no effect on humans, birds, or any other higher creatures other than protecting them from diseases. There were guys who fell into vats of the stuff in the 1950s and one guy who used to eat the stuff with a spoon on television to demonstrate its safety, all with no ill effects.
The most major problem with it was that patents had all expired by WW-2 and the time they discovered its effect on insects, so that there was no way for any one company to make giant profits with it.
http://junksciencearchive.com/ddtfaq.html
https://www.thedailybeast.com/how-rachel-carson-cost-millions-of-people-their-lives