Okay, on a serious note.
There's basically two problems, the incoming stream of newly diagnosed autistics (the influx) and the massive, massive reservoir of already diagnosed, of all ages (the overflow). The influx problem is simple enough to deal with, simply have the diagnosing physician quickly and humanely administer a surgical hammer to the base of the upper spine apon diagnosis. Little mess, little fuss, generally humane, and in all honesty it doesn't take any specialised training, so it could be delegated to a nurse or orderly if the doctor in question has an objection to performing the procedure himself (a sore elbow, or what have you). Clinics that specialise in the diagnosis of autism might want to invest in captive bolt guns and rubber sheeting to catch any incidental mess but really, that's up to them.
The overflow is a slightly trickier problem. Obviously everybody's first thought runs to cattle carts and gas chambers, as popularised by the Third Reich, but I posit that the mass transportation of autistics for orderly disposal is overcomplicated and uneccessary. Camps like Buchenwald and Auschwitz were founded on the Nazi's original plans to intern Jews for the duration of the war instead of exterminating them, and we simply cannot afford to show the kind of weak wishy-washy compassion that Nazis became famous for when we're dealing with autistics. The opposite extreme would be a Balkan or Cambodian style free-for-all in which poorly trained or completely untrained militias are let loose to deal with the autists as they see fit. While this seems a less costly solution, we have to take into account lost work-hours, damage to property by well-meaning but overexcited militiamen, and the inevitable possibility that some opportunistic folks will falsely label their enemies autists as an excuse to kill them. We need less governmental oversight than the Nazi method, but more than the Balkan method.
I propose we look to Latin America, specifically political suppressions in countries like Guatamala and Nicuaragua. Autistics are already documented in the medical system, so we have our "kill list". All that's needed now is a few black helicopters to ferry some highly professional military personnel around in the dead of the night, going house-to-house and disposing of all documented autistics. I'd generally advise machetes and bayonets only, but if there are any morale issues concerning being sent into lethal engagements without the use of firearms, frangible ammunition and less-lethal chemical agents could certainly be authorised, to minimise destruction of property and unwanted collateral killings while still ensuring the safety of our operatives.
Good enough?
