(HealthDay News) – The rates of both community-onset and hospital-onset methicillin-resistant Staphylococcus aureus (MRSA) bacteremia decreased from 2005–2010 among military personnel.
Michael L. Landrum, MD, from the San Antonio Military Medical Center, and colleagues used medical record databases to identify and classify all annual first-positive S. aureus blood and wound or abscess cultures as methicillin-susceptible S. aureus or MRSA. Onset was classified as community-onset or hospital-onset infections in isolates collected more than three days after hospital admission.
The researchers found that annual incidence rates for S. aureus bacteremia varied from 3.6–6.0 per 100,000 person-years; annual incidence rates for S. aureus skin and soft tissue infections (SSTIs) varied from 122.7–168.9 per 100,000 person-years. From 2005–2010 there was a decrease in the annual incidence rates for both community-onset MRSA bacteremia (1.7 per 100,000 person-years [95% confidence interval (CI), 1.5–2.0 per 100,000 person-years] to 1.2 per 100,000 person-years [95% CI, 0.9–1.4 per 100,000 person-years]) as well as hospital-onset MRSA bacteremia (0.7 per 100,000 person-years [95% CI, 0.6–0.9 per 100,000 person-years] to 0.4 per 100,000 person-years [95% CI, 0.3–0.5 per 100,000 person-years]). The proportion of MRSA-related community-onset SSTI peaked at 62% in 2006 and then significantly decreased annually to 52% in 2010.
“In the Department of Defense population consisting of men and women of all ages from across the United States, the rates of both community-onset and hospital-onset MRSA bacteremia decreased in parallel, while the proportion of community-onset SSTIs due to MRSA has more recently declined,” the authors write.