I'm so old I can remember something so simple as a product called Smear62 eliminated the screw worm problem. Now, we have to spend 8.5 million on a facility to produce sterile flies to combat the problem? (https://www.oann.com/newsroom/u-s-to-build-8-5m-fly-breeding-facility-to-fight-cattle-parasite-outbreak/), If the gov. wants sterile flies why not convert their facility to make sterile mosquitoes into making these flies?
I am going to make a wag that the livestock population was even higher back then than it is now.

Actually, the process of sterilization is a proven remedy, and they (screw worm flies) were considered eradicated as late as the mid to late 90's, but I still think 8.5 M is exorbitant!

https://www.nal.usda.gov/colle...tion-program-records.
A scroll down to timeline is interesting for many reasons.