Either not having my coffee yet or lacking basic elements of an understanding of medicine is getting in my way of understanding this good news:

Children who attend daycare or playgroups cut their risk of the most common type of childhood leukaemia by around 30%, a study estimates. Researchers reviewed 14 studies involving nearly 20,000 children, of which 6,000 developed acute lymphoblastic leukaemia (ALL). It is thought early infections may help the body fight off the disease.

Coincidence or cause? More interesting to note that leukaemia is stated to be the most common cancer found in children in the industrialized world - leading me to wonder what the rate reduction is for not associating yourself with an industrialized world.