Hmm, that seems to contradict the article directly - insecticides were used to try to battle screwworm initially and were not really effective - the solution was using sterile male flies to stop reproduction - which would work in South America just as well as it did in North (with sufficient scale)

You and the article are correct so I erased my comment.

I found and read through some of the reports of the time to try and prove myself correct. I'm wrong.

https://www.nal.usda.gov/exhibits/speccoll/exhibits/show/sto...