Healthcare-associated Methicillin Resistant Staphylococcus aureus (HA-MRSA)

Overview of Healthcare-associated MRSA

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staph bacteria that does not react to certain antibiotics and will normally cause skin infections, but MRSA can also cause other infections— including pneumonia. MRSA can be fatal. In 1974, MRSA infections accounted for two percent of the total number of staph infections; in 1995 it was 22%; in 2004 it was 63%. CDC estimated that 94,360 invasive MRSA infections occurred in the United States in 2005; 18,650 of these were associated with death. MRSA is resistant to antibiotics including methicillin, oxacillin, penicillin, and amoxicillin. Since these strong drugs are not effective with MRSA, these infections are sometimes called Multidrug-Resistant Organisms (MDROs). Staph infections, including MRSA, occur most often among people in hospitals and healthcare facilities (such as nursing homes and dialysis centers) who have weakened immune systems. The infection can be spread by skin-to-skin contact, sharing or touching a personal item with someone with infected skin, or touching a surface or item that has been in contact with someone with MRSA.

MRSA infections that occur in otherwise healthy people who have not been recently (within the past year) hospitalized or had a medical procedure (such as dialysis, surgery, catheters) are known as community-associated MRSA infections (CA-MRSA). These infections are usually skin infections such as abscesses, boils, and other pus-filled lesions, but these infections may also lead to more serious illness, such as pneumonia. (See Community-associated MRSA. )

What to Look for?

Most staph infections, including MRSA, will grow as a bump or infected area on the skin. You should look for skin that is:

  • Red
  • Swollen
  • Painful
  • Warm to the touch
  • Full of pus or other drainage
  • Accompanied by a fever

The Good News

Major strides have been made in recent years to reduce the numbers of MRSA infections in healthcare settings. See the Prevention page to learn more.

Background/General Information



Date last modified: March 3, 2010
Content source: 
Division of Healthcare Quality Promotion (DHQP)
National Center for Preparedness, Detection, and Control of Infectious Diseases (NCPDCID)