...well if you have an autoimmune disease, that is.So basically, the idea is that if you have a disease like multiple sclerosis or Crohn's where your immune system is going nuts and destroying your own body, a possible solution is to swallow some nematodes, specifically human whipworms, pig whipworms, or hookworms. The idea comes from evolution being applied to medicine, and it actually sounds fairly promising (Take that, fundies!).
The idea is that before we had modern medicine and super-clean environments, parasites were a very real danger for most of humanity. You probably know that when any foreign biological matter enters our bodies, our immune systems attack and destroy it. Parasites aren't exempt from this. So over time, they evolved mechanisms to suppress the immune systems of the hosts they infect, which included our ancestors. In response, our ancestors evolved more robust immune systems that could counter the defenses of the parasites, and a sort of balance was attained. Now take away the parasites and throw in sterile environments, and you have very strong immune systems with nothing to fight, so they turn on their own bodies. The fact that the developing world, known for being dirtier than the West, has substantially fewer cases of autoimmune disease among their populations seems to support this hypothesis.
So a possible solution would be to intentionally infect patients suffering from certain autoimmune diseases with parasites. Pig whipworms are considered the safest. Since they evolved in pigs, they can't successfully reproduce in humans, so they're easier to control and can't develop into an infection that spirals out of control.
Clinical trials are already under way. Here are a few stats from the article:
For the next three months, he [a patient with MS] and four others visited the lab every two weeks to swallow doses of 2,500 parasite eggs. At the start of the trial, MRI scans showed patients had an average of 6.6 active lesions – scars on the protective layer around nerve cells that disrupt the transmission of electrical messages in the brain and spinal cord. By the end of the study, that number had dropped to two. Two months after discontinuing the worm treatment, the lesions rebounded to an average of 5.8.
In 1999, when Elliott and Weinstock first found that helminths protected mice against colitis, news spread fast. Six years later, the group published the result of two preliminary trials in humans. In one, involving 54 ulcerative colitis patients, 43% of those given pig whipworm eggs improved, compared with only 17% who received placebos. In a second trial 29 patients with Crohn’s disease took whipworm eggs every three weeks. By the end of 24 weeks, 79% had reduced disease activity and 72% had gone into remission.