Vital Signs

Trends in Staphylococcus Aureus Infections in Veterans Affairs Medical Centers — United States, 2005–2017

Makoto Jones, MD; John A. Jernigan, MD; Martin E. Evans, MD; Gary A. Roselle, MD; Kelly M. Hatfield, MSPH; Matthew H. Samore, MD


Morbidity and Mortality Weekly Report. 2019;68(9):220-224. 

In This Article

Abstract and Introduction


Introduction: By 2007, all Department of Veterans Affairs medical centers (VAMCs) had initiated a multifaceted methicillin-resistant Staphylococcus aureus (MRSA) prevention program. MRSA and methicillin-susceptible S. aureus (MSSA) infection rates among VAMC inpatients from 2005 to 2017 were assessed.

Methods: Clinical microbiology data from any patient admitted to an acute-care VAMC in the United States from 2005 through 2017 and trends in hospital-acquired MRSA colonization were examined.

Results: S. aureus infections decreased by 43% overall during the study period (p<0.001), driven primarily by decreases in MRSA, which decreased by 55% (p<0.001), whereas MSSA decreased by 12% (p = 0.003). Hospital-onset MRSA and MSSA infections decreased by 66% (p<0.001) and 19% (p = 0.02), respectively. Community-onset MRSA infections decreased by 41% (p<0.001), whereas MSSA infections showed no significant decline. Acquisition of MRSA colonization decreased 78% during 2008–2017 (17% annually, p<0.001). MRSA infection rates declined more sharply among patients who had negative admission surveillance MRSA screening tests (annual 9.7% decline) compared with those among patients with positive admission MRSA screening tests (4.2%) (p<0.05).

Conclusions and Implications for Public Health Practice: Significant reductions in S. aureus infection following the VAMC intervention were led primarily by decreases in MRSA. Moreover, MRSA infection declines were much larger among patients not carrying MRSA at the time of admission than among those who were. Taken together, these results suggest that decreased MRSA transmission played a substantial role in reducing overall S. aureus infections at VAMCs. Recent calls to withdraw infection control interventions designed to prevent MRSA transmission might be premature and inadvisable, at least until more is known about effective control of bacterial pathogen transmission in health care settings. Effective S. aureus prevention strategies require a multifaceted approach that includes adherence to current CDC recommendations for preventing not only device- and procedure-associated infections, but also transmission of health care–prevalent strains.


Staphylococcus aureus is among the most common causes of health care–associated infections and accounts for significant morbidity and mortality. Beginning in 2005, in response to high rates of methicillin-resistant S. aureus (MRSA) infections, the U.S. Department of Veterans Affairs (VA) piloted an MRSA prevention program in 18 VA medical centers (VAMCs). By October 2007, all 153 VAMCs had implemented the MRSA prevention program, which included, among other components, admission screening for nasal MRSA carriage and using contact precautions (i.e., wearing a gown and gloves for all interactions involving contact with the patient or the patient's environment) for patients found to be carriers.[1] To assess the impact of the intervention, the investigators tracked the incidence of MRSA and methicillin-susceptible S. aureus (MSSA) infections at 130 VAMCs from 2005 to 2017 and examined hospital-acquired MRSA colonization based on results of MRSA surveillance tests collected during the same period.