Personally, I know that my immune system is actually in overdrive (i.e. - "too strong" as opposed to "too weak"). I developed Rosacea in 2005, and then Multiple Sclerosis in 2007. MS is an autoimmune inflammatory disease (as Rosacea also appears to be).
Other autoimmune / inflammatory conditions run in my family, including eczema, hives, allergies, hypothyroidism, and Type 1 (juvenile onset) diabetes.
This cannot be a coincidence.
I am curious as to how many others with Rosacea have family histories involving autoimmune / inflammatory diseases.