An immunodeficiency is a pathological situation linked to the insufficiency of one or more immunological functions (we also speak of "depression" or "deficiency" or even "immune dysfunction").

The consequences of an immune deficiency are mainly infectious.

Pathogenic germs that can cause very severe infections. However, in an immune-depressed organism germs which are usually non-pathogenic for humans and which, for example, come from the air, water3, soil or food can also cause serious infections, called "opportunistic infections".

An immunodeficiency can cause healing difficulties4 and / or other pathologies, in particular tumors, malignant tumors, cancer or leukemia.