Getting a dose of a hookworm, an African parasite, could help with asthma and allergies. The hygiene hypothesis suggests that we get more allergies now because our immune systems don’t have enough to do – so perhaps the hookworm distracts the immune system and gives it something to work on? I wouldn’t try this at home, at least until researchers have finished clinical trials.

See the paper in Journal of Immunology – from Discover’s 20 Things You Didn’t Know About… Allergies