Staphylococcus is an abbreviation for a common bacteria called “Staphylococcus aureus”. Staphylococcus bacteria often exist on the skin without causing infection. The infection develops if they penetrate the skin. This causes redness, tenderness, swelling, and sometimes runny discharge. Opportunistic microorganisms in normal circumstances do not pose a threat (the human immune system easily copes with them and they do not require treatment). But if there are favorable conditions, opportunistic representatives of the genus cause staphylococcal infection. Invasion of staphylococci can cause many different diseases, affecting almost any organ or tissue in the human body. Some of these diseases do not pose a threat, others can even lead to death.