Ah... No.
You're mixing in immune disorders with superbugs, but the two are not related. MRSA and related infections are almost certainly products of the overuse and misuse of antibiotics. Most people only take antibiotics until they feel better, but if you don't complete the course (which often means taking them for some time after feeling fully recovered) the bacteria which survive can adapt and resist.

The rise of immune conditions (and, I think, some sorts of allergy) has been suggested to be linked to much greater cleanliness in our homes. We need a certain amount of exposure to dust and dirt and germs in order to build a healthy immune system. The parallel is in how vaccines work - a weak or inactive form of the disease is used to train the body's immune system to fight off the stronger types.

Think of the ending of War of the Worlds if you want another example...
( MatJ LOOK, Fri 3 Feb 2012, 8:20, Reply)