Staph Infection (Staphylococcus Aureus)

  • Medical Author:
    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

  • Medical Editor: William C. Shiel Jr., MD, FACP, FACR
    William C. Shiel Jr., MD, FACP, FACR

    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Quick GuideWhat Is a Staph Infection? Symptoms, Pictures

What Is a Staph Infection? Symptoms, Pictures

What is Staphylococcus? What causes a staph infection?

Staphylococcus is a group of bacteria (microbe or germ) that can cause a number of infectious diseases in various tissues of the body. Staphylococcus is more familiarly known as staph (pronounced "staff"). Staph-related illness can range from mild and requiring no treatment to severe and potentially fatal.

The name Staphylococcus comes from the Greek staphyle, meaning a bunch of grapes, and kokkos, meaning berry, and that is what staph bacteria look like under the microscope, like a bunch of grapes or little round berries. (In technical terms, these are gram-positive, facultative anaerobic, usually unencapsulated cocci.)

Over 30 different types of staphylococci can infect humans, but most infections are caused by Staphylococcus aureus. Staphylococci can be found normally in the nose and on the skin (and less commonly in other locations) of around 25%-30% of healthy adults and in 25% of hospital or medical workers. In the majority of cases, the bacteria do not cause disease. However, a cut, abrasion, or other damage to the skin or other injury may allow the bacteria to overcome the natural protective mechanisms of the body, leading to infection.

Reviewed on 6/12/2017
References
REFERENCES:

Baorto, Elizabeth P. "Staphylococcus Aureus Infection." Medscape.com. June 30, 2016. <http://emedicine.medscape.com/article/971358-overview>.

Herchline, Thomas. "Staphylococcal Infections." Medscape.com. Apr. 7, 2017. <http://emedicine.medscape.com/article/228816-overview>.

Smith, Darvin Scott. "Bacterial Infections and Pregnancy." Medscape.com. Aug. 25, 2016. <http://emedicine.medscape.com/article/235054-overview>.

United States. Centers for Disease Control and Prevention. "Methicillin-resistant Staphylococcus aureus (MRSA)." Mar. 25, 2016.

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