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Staphylococcus aureus Infections

(Staph Infections)


The Manual's Editorial Staff

Last full review/revision Oct 2019| Content last modified Oct 2019
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What is Staphylococcus aureus?

Staphylococcus ("staph") are a common group of bacteria. Some types of staph normally live on people's skin and in the environment and don't cause disease. Other types of staph, particularly Staphylococcus aureus, can cause serious infections. They're often called simply staph infections.

  • You can get a staph infection from another person or by touching objects that have the bacteria on them

  • Staph infections can be mild or deadly

  • Staph bacteria that get in your bloodstream can cause problems in your organs

  • Doctors treat staph infections with antibiotics

  • Many staph infections are resistant to common antibiotics

  • You can help prevent staph infections by washing your hands thoroughly

What is MRSA?

Staph infections used to be cured by many antibiotics. Now many types of staph have become resistant to all but the strongest antibiotics. Staph that can’t be cured by one group of common antibiotics is called MRSA (methicillin-resistant Staphylococcus aureus). MRSA and other even more resistant types of staph are becoming more common, especially in hospitals. These infections are hard to treat.

What causes staph infections?

Staph infections can spread easily by:

  • Touching another person who has the infection

  • Touching objects with the bacteria on them (such as gym equipment, telephones, door knobs, remote controls, or elevator buttons)

Staph usually infects your:

  • Skin

However, staph can move through your bloodstream and infect almost any place in your body. such as the valves in your heart and your bones. Staph also may stick to medical devices in your body, such as a pacemaker, an artificial joint, or heart valve.

What are staph carriers?

Some people have staph bacteria on their skin or in their nose but have no symptoms. These people are called carriers. Carriers can spread the bacteria to other people and give them an infection. People who work in hospitals or are patients in hospitals are more likely to be carriers.

What are the symptoms of staph infections?

If you have a staph infection on your skin, you may have:

  • Pain and redness of your skin (cellulitis)

  • Itchy or painful blisters filled with white or yellow fluid that break and leave crusts (impetigo)

  • Painful, pus-filled swellings under your skin (abscesses)

If you have a staph infection somewhere else on your body, you may have other symptoms:

  • Breast infection (mastitis): Pain, redness, and abscesses (pockets of pus) on the breast, which are common in breastfeeding mothers usually 1 to 4 weeks after beginning to breastfeed

  • Lung infection (pneumonia): Often a high fever, shortness of breath, and a cough with bloody spit

  • Blood infection (sepsis): High fever and sometimes a dangerously low drop in blood pressure (septic shock)

  • Heart valve infection (endocarditis): Fever and shortness of breath —this can be deadly

  • Bone infection (osteomyelitis): Chills, fever, bone pain, and redness and swelling in the skin above the bone

How can doctors tell if I have a staph infection?

Doctors can usually recognize a staph skin infection by examining it. To tell if you have other types of staph infections, doctors will do tests such as:

  • A blood test

  • A test of infected body fluids

How do doctors treat staph infections?

Doctors treat staph infections with antibiotics. If you got the infection in a hospital, they’ll give you antibiotics that work against MRSA.

  • Sometimes skin infections can be treated with an ointment that you put on your skin

  • If your skin infection is more severe, you'll be given antibiotics to take by mouth or sometimes by vein

  • Bone infections usually need surgery to take out the infected bone tissue

  • If you have an abscess, doctors will cut it open and drain the pus

How can I prevent staph infections?

  • Wash your hands thoroughly with soap and water or use hand sanitizer

  • Don't cook or prepare food for others if you have a staph infection of your skin

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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