They should stop beating around the bush and just carpet bomb all CIA related countries. Get rid of some bad genetics along the way as well.
That would be killing all the people of Iraq, Syria, Turkey and Nigeria (via Boko Haram). Including Christians, Jews, Muslims and more.
Depending on how you define "related countries", that could be any country with members of CIA operating within it.
That extends out much further, to Cameroon, Chad, Egypt, Pakistan, etc.