Staph Infection

(Staphylococcus Infection)


A staph infection is an illness caused by a common bacteria. It may cause a simple skin infection or lead to an infection in the bloodstream or major organs. Staph infections may be:

  • MSSA—often sensitive to common antibiotics
  • MRSA—may not be as sensitive to common antibiotics


The bacteria that cause staph infections can often be found on the skin. An infection develops when the bacteria enters the body through a break in the skin. The bacteria may only affect local skin tissue or can enter the bloodstream. Once in the blood, it can pass to other areas of the body such as the heart, bones, or joints.

Staph Bacteria Can Enter the Body Through Breaks in the Skin

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Risk Factors

An open wound in your skin increases your risk of infection. This includes minor cuts, punctures, scrapes or surgical wounds.

Other factors that can increase your chance of general infection include:

  • Health conditions or treatments that weaken the immune system
  • Medicine that lowers the immune system
  • Current recovery from serious illness or surgery


Symptoms will depend on the location of the infection and if the infection has spread.

An infection in the skin may create an area with:

  • Redness
  • Swelling
  • Pain
  • Feeling warm to touch

You may also have a fever and drainage/pus or crusting at the site.

Infections that have spread to other areas of the body may cause:

  • Fever and chills
  • General ill feeling
  • Nausea/vomiting
  • Achiness
  • Headache
  • Swollen joints
  • Trouble breathing


Your doctor will ask about your symptoms and past health. The infected area will be examined. Your doctor may suspect a staph infection based on the exam. A sample of the affected area may also be taken and sent to a lab. The lab will be able to confirm the specific type of bacteria causing the problem.


Treatment will be based on the specific infection and your overall health. One or more of the following may be needed:

  • Incision and drainage of the infected area
  • Antibiotic treatment—pills, cream applied to skin, or IV for severe illnesses. Taking the entire antibiotic treatment is important to prevent recurrence

Drainage from the wound is very contagious. It can spread the infection to others.


To help reduce the chance of a staph infection:

  • Wash your hands often. Use soap and water or hand sanitizers.
  • Make sure medical personnel wash their hands before delivering care.
  • Do not share personal items such as towels, athletic equipment, or razors.
  • Keep cuts and wounds clean and covered until healed.
  • Launder clothing and bed sheets on a regular basis. Wash gym and athletic clothes after each wear. Wash towels after each use.
  • Avoid contact with other people’s wounds and materials used to cover or treat wounds.
  • Shower right after sports activities. Use soap and water.
  • Avoid group sports if you have an open wound that appears infected.


Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases


Public Health Agency of Canada


Methicillin-resistant Staphylococcus aureus (MRSA) infection. EBSCO DynaMed Plus website. Available at: http://www.dynamed.... Updated May 21, 2019. Accessed October 2, 2019.
Staph infections. Kids Health—Nemours Foundation website. Available at:
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Updated June 2014. Accessed October 2, 2019.
Staphylococcus aureus. Minnesota Department of Health website. Available at:
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Accessed October 2, 2019.
Last reviewed October 2019 by David L. Horn, MD, FACP