Feeling ill? Swallow a worm

Early trials suggest a host of allergies and autoimmune ailments could be treated with worm therapy, or infection with live worm-like parasites. But will it ever reach the clinic?

Jim Turk initially put his symptoms down to stress. The self-described "health nut" who was in training to run marathons suddenly found himself unable to jog for more than a couple of minutes before coming to a gasping, staggering halt.