There is no life and no surviving without immunity. Immunity takes care that the integrity of our bodies is sustained, that the many boundaries that make up an organism, are closed and open for the environment at the same moment. Immunity is like a gating device actively controlling and maintaining all boundary surfaces.
A very demanding job, it is therefore not amazing that immune issues are widely spread among all species. Without immunity all organism dissolve and merge with the environment.
We also call this process passing away. Biestmilch is highly supportive in keeping the balance between the in- and out-currents of the most distinct molecules along all bodily boundaries.