The agent may no longer be Orange, but I believe the USAF still has one unit capable of doing the spraying; an Air National Guard unit out of Rickenbacher ANG Base in Columbus Ohio. They used C-123 Providers during the Vietnam era, upgraded to old C-130s in the late 80s.
Found this:
infowars.com/articles/new_orleans/airplanes_spray_for_mosquitoes.htm
Pitts2112