Fighting Allergies by Mimicking Parasitic Worms

This makes a lot of sense, I've wondered why allergies seem so much more prevalent today:

Technology Review: Fighting Allergies by Mimicking Parasitic Worms: "As blossoming spring trees spew pollen, many allergy sufferers would be grateful for a more effective way to alleviate their itchy misery. How about swallowing a batch of pig whipworm eggs, or deliberately infecting oneself with the fecal-dwelling hookworm? Yucky as these options sound, mounting evidence in both humans and animals suggests that infection with these parasitic worms seems to protect against a number of inflammatory diseases, including asthma and allergy, multiple sclerosis, Crohn's disease, and type 1 diabetes."