science

Basically Burkina Faso went out on a limb allowing them to launch the program, either not fully realizing that the mosquitos would eventually cross boarders and make this an international incident or just deciding they didn't care and would do it anyway.

Burkina Faso is in the process of merging with several other countries to make a federated union in tha Sahel, most likely one of the other nations in the Pact found out about it and objected so they are coming down hard to save face.

Essentially there is enough skepticism of the technology among the African populace that this is now becoming a third rail issue for politicians. Those countries independent enough to not care what their neighbors think have populations against the technology, and everyone else is internationally minded enough to defer to the objectors.

That said, pesticide or no, the cat may be well out of the bag at this point, if a few of the test release mosquitoes survive it will only be a matter of time before the genes spread through the population. That's the whole point of the gene drive.