The immune system in the water body is maintaining steadily by numerous bacterium, algae. Like the bacterium in the human large intestine helps us to absorb.

Sources sof the bacterium include uncooked produce, raw milk, unpasteurized juice, contaminated water and meat, especially undercooked or raw hamburger.

Sphaerotilus is a kind of filamentous bacterium with typical sheath forming. It occurs mainly in activated sludge and polluted water.