Both of the suggestions above are very good ones. I highly recommend following Trapper's advice about iodine. And a good parasite cleanse is usually a good idea too.
You may also wish to take a look at Jon Barron's Blood Support product for help with cleansing and strengthening the blood. Black Cumin (Nigella sativa) seed oil is also reputed to be very good for eliminating parasites. You might want to check out the black seed forum for more info, as we have a black seed expert over there.
Regarding autism, have you been following some of the instances of addressing autism with Vitamin D3?