If I hadn't gone into astronomy, I think I'd be an epidemiologist. Quotes from the article (as warning, or enticement):
"And the disease that confronted doctors at the Austin Medical Center here last fall was strange indeed. Three patients had the same highly unusual set of symptoms: fatigue, pain, weakness, numbness and tingling in the legs and feet. The patients had something else in common, too: all worked at Quality Pork Processors, a local meatpacking plant."
"The plant owner watched for a while and said, 'Let’s stop harvesting brains.'"
"'I always had brains on my arms,' she said."
"'I think we’ll learn a lot, but it may take us a while. It’s a great detective story.'”
http://www.nytimes.com/2008/02/05/health/05pork.html