Very interesting information about how infections can cause autism:
http://www.canlyme.com/autismlyme.html
http://www.lymeinducedautism.com/lymeautismconnection.html
http://www.lymeinducedautism.com/presentations.html
http://www.personalconsult.com/articles/aapdd.html
http://www.ilads.org/lyme_research/lyme_articles1.html