They Like Your Guts; February 2011; Scientific American Magazine; by Ferris Jabr; 1 Page(s)

In 2007 parasite immunologist P’ng Loke sat down for lunch at a University of California, San Francisco, cafeteria with a patient who wanted help documenting his medical condition. The two shared an unusual interest: gut worms—specifically, tiny wormlike parasitic organisms called helminths.

Loke’s 35-year-old guest, who declined to be identified for reasons of patient confidentiality, explained that he suffered from an inflammatory bowel disease known as ulcerative colitis. While researching his condition a few years before, the man had read about helminthic therapy, which has not been approved by the FDA but which is a subject of active research by gastroenterologists and parasitologists. The idea is that people with autoimmune disorders can ease their symptoms by deliberately infecting themselves with parasitic worms such as hookworm or whipworm, both of which supposedly pacify the human immune system to survive inside the body. In numerous animal studies, these parasites ostensibly protected rodents from a wide variety of immunological disorders, including colitis, asthma, rheumatoid arthritis, food allergies and type 1 diabetes. The man had convinced himself the therapy could work for him, and, since 2004, he had been ingesting whipworm eggs, which he obtained from Thailand. He was now virtually symptom-free. Could Loke help him figure out how, if at all, the worms had treated his colitis?