Further study findings suggested that bacteria and fungi are not causing an infection in the sinuses, but rather, that the immune system was responding to commensals, microorganisms that, themselves, do not harm the human body. When the immune system reacts in a hyper-responsive way, unnecessarily fighting off a harmless microorganism, it can initiate an immune response like inflammation. The body can then get locked into a cycle where inflammation generates more inflammation, causing a chronic condition.
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