The smallest unicellular organisms that can live inside a person or come from outside. They can be both beneficial and pathogenic.
Make up a useful intestinal microflora. Improves digestion. Supports the immune system. Produce vitamins the body needs.
Cause angina, intestinal infections, erysipelas, dysentery, salmonellosis, tuberculosis, diphtheria, whooping cough, tetanus, various inflammatory and purulent processes.