Hookworms and Allergies

This is gross, but this study seems to indicate the hookworm infections seem to reduce allergic symptoms like asthma.

The idea is that allergies are a result of an immune system that is over-reactive, and something produced by the parasites helps suppress the immune response. As a side effect of the immune system attacking the worms less stridently, it also responds less to other allergens that make our eyes water, nose run, and airways contract.

The idea here is to try and figure out how the worms reduce the immune response, but many people say just give them a few worms and see no adverse effects. It's still seems gross though...