MRSA Tracking

A full picture of invasive MRSA infections is possible using CDC’s two complimentary systems:

• Emerging Infections Program (EIP) –surveillance representative of the whole country.
• National Healthcare Safety Network (NHSN) – data entered from hospitals.

HHS Action Plan – targets and metrics toward reducing specific HAIs, including MRSA.

National Estimates and Adjusted Incidence Rates of Invasive MRSA Infections

Epidemiologic Category	Estimated Cases of Infection
	Non-Dialysis Patients		Dialysis Patients		Total
	Estimated No.	Incidence Rate (Confidence Interval)a	Estimated No.	Incidence Rate (Confidence Interval)b	Estimated No.	Incidence Rate (Confidence Interval)
CA	15,138	4.82 (3.69-6.42)	NA	NA	15,138	4.82 (3.69-6.42)
HCA	44,771	14.29 (12.40-16.62)	14,041	3262.39 (2496.82-4247.12)	58,812	18.74 (15.81-22.42)
HCA-HO	11,493	3.67 (2.73-5.02)	1,408	327.24  (131.31-739.07)	12,901	4.11 (2.90-6.02)
HCA-HACO	61,268	10.62 (9.06-12.55)	12,633	2936.08 (2216.06-3876.65)	45,911	14.63 (12.09-17.85)
Overallc	65,296	19.54 (17.24-22.31)	14,041	3263.31 (2496.12-4248.98)	75,309	23.99 (20.64-28.10)

^aNational Estimates and Incidence (no. per 100,000 population per year) are adjusted for age,  race, gender and receipt of chronic dialysis using 2012 US Census Data.
^bNational Estimates and Incidence (no. per 100,000 dialysis patients per year) for dialysis patients are adjusted for age, race and gender using 2011 USRDS point prevalence data.
^c80 cases could not be classified into an epidemiological category or category is unknown and therefore are counted in the overall estimate only.
^dStarting in 2011, confidence intervals on national estimates were determined for each of the 72 age/race/gender/dialysis specific strata and summarized for an overall national estimate, accounting for variance across all strata producing a more conservative estimate (with wider confidence intervals) compared to estimates prior to 2011.

Source: Centers for Disease Control and Prevention. Active Bacterial Core Surveillance Report, Emerging Infections Program Network, Methicillin-Resistant Staphylococcus aureus, 2012 [PDF - 241 KB].

Additional Information

Studies show that about one in three (33%) people carry staph in their nose, usually without any illness. Two in 100 people carry MRSA. There are not data showing the total number of people who get MRSA skin infections in the community.

Although MRSA is still a major patient threat, a CDC study published in the Journal of the American Medical Association Internal Medicine showed that invasive (life-threatening) MRSA infections in healthcare settings are declining. Invasive MRSA infections that began in hospitals declined 54% between 2005 and 2011, with 30,800 fewer severe MRSA infections. In addition, the study showed 9,000 fewer deaths in hospital patients in 2011 versus 2005.

This study (or report) complements data from the National Healthcare Safety Network (NHSN) that found rates of MRSA bloodstream infections occurring in hospitalized patients fell nearly 50% from 1997 to 2007.

Taken together and with other reports such as the March 2011 CDC Vital Signs article [PDF - 2.75 MB], and a 2013 study showing a decrease in overall central line-associated bloodstream infections, these studies provide evidence that rates of hospital-onset, severe MRSA infections in the United States are falling. While MRSA remains an important public health problem and more remains to be done to further decrease risks of developing these infections, this decrease in healthcare-associated MRSA infections is encouraging.

For more information about CDC surveillance programs and reports related to MRSA, visit:

• CDC MRSA website
• CDC Active Bacterial Core Surveillance
• CDC Vital Signs Report [PDF - 2.75 MB]
• National Healthcare Safety Network
• NHSN Annual Reports
• CDC Safe Healthcare Blog
• CDC Funding to Prevent HAIs including MRSA

To see how states are working to prevent HAIs including MRSA, view this interactive map of state-based prevention activities.

Top