This is an astonishing finding.

It seems that in freeing ourselves from parasites which, in evolutionary terms, we had been obliged to learn to live with, we may have caused ourselves a whole set of unforeseen problems.

So, next time you break out your Kills 100% of all known germs - DEAD kitchen/bathroom/house cleaning fluid, remind yourself that maybe some of those known germs might have their uses, from a human point of view!!

(And ask yourself what a germ that had been killed UNDEAD might be like...)