Methicillin-resistant Staphylococcus aureus (MRSA) was responsible for an estimated 94,000 life-threatening infections and 18,650 deaths in 2005, CDC researchers report in the Oct. 17 issue of The Journal of the American Medical Association.
That same year, roughly 16,000 people in the U.S. died from AIDS, according to CDC figures.
The national estimate is more than double the invasive MRSA prevalence reported by CDC researchers five years earlier, says researcher R. Monina Klevens, DDS, MPH.
"MRSA infections are an important public health problem that can no longer be ignored," she tells WebMD. "We need to put this higher on our list of priorities."
Among the highlights from the newly published study:
- While most invasive MRSA infections could be traced to a hospital stay or some other health care exposure, about 15% of invasive infections occurred in people with no known health care risk.
- Two-thirds of the 85% of MRSA infections that could be traced to hospital stays or other health care exposures occurred among people who were no longer hospitalized.
- People over age 65 were four times more likely than the general population to get an MRSA infection. Incidence rates among blacks were twice that of the general population, and rates were lowest among children over the age of 4 and teens.
Known as a superbug because it is resistant to so many antibiotics, MRSA infection is seen most often in patients who have undergone invasive medical procedures or who have weakened immune systems.
Invasive MRSA is a leading cause of potentially life-threatening bloodstream infections, surgical site infections, and pneumonia.
It has been clear for some time that MRSA was a growing problem in the nation's hospitals and other health care settings, but the extent of the problem at the national level has not been well known.
The CDC researchers analyzed 2005 data on invasive MRSA infections from nine sites across the country to arrive at the national prevalence figures.