As said we all carry staph bacteria and there is nothing wrong with it. but can we carry invasive strain and not know about it?

Staph: The body immune system, especially the skin protects the body from bacterial infections. Our ability to survive is dependent on our immune system. Let us say you have a cut and you don't clean it, then there is a break in the defense and a lack of expected hygiene which can contribute to an infection. All staph on the skin is easily killed by soap and water.