Staph infections are caused by bacteria called Staphylococcus aureus. These bacteria can live on the skin and in the nose of healthy people, without causing any harm. However, if the bacteria enter the body through a cut or other break in the skin, they can cause an infection.
Staph infections can range from minor skin infections to life-threatening conditions such as sepsis. Symptoms of a staph infection can include redness, swelling, pain, and drainage from the infected area. In some cases, staph infections can also cause fever, chills, and nausea.