Methicillin-resistant Staphylococcus aureus bloodstream infections among some of the most vulnerable patients in a hospital – those in the intensive-care unit (ICU) – have dropped dramatically between 1997 and 2007, according to a report released by the Centers for Disease Control and Prevention on Tuesday.
The report is detailed in Wednesday’s Journal of the American Medical Association.
Dr. Deron Burton of the CDC and colleagues studied hospital data on blood infections caused by tubes inserted into veins known as central line catheters. During the study period, 1,684 intensive care units reported a total of 33,587 blood infections caused central line catheters. Of those, 7.4 percent were MRSA and 4.7 percent were methicillin-susceptible Staphylococcus aureus (MSSA), meaning the infection could be treated with the antibiotic.
The number of MRSA infections dropped by close to 50 percent after 2001 and continued through 2007, the researchers found. The decline was seen in all types of ICUs – 51.5 percent in medical-surgical ICUs and by more than 69 percent in surgical ICUs.
This drop was visible not only in the case of MRSA infections.
“We looked at bloodstream infections being caused by any pathogen, not just MRSA. When we looked at all causes of these central line bloodstream infections lumped together, we saw declines of roughly 40 to 50 percent in the risk of these infections. Hospitals should be encouraged by these results. Their efforts should be continued and expanded,” Burton said.
The results of the study are visible signs that doctors and nurses are working harder to prevent infections by frequent hand-washing, instrument sterilization and other measures.
MRSA infection is caused by Staphylococcus aureus bacteria, a strain of staph that is resistant to the broad-spectrum antibiotics called the beta-lactams, which include the penicillins and the cephalosporins. MRSA first emerged in hospitals in the 1960s.
Most MRSA infections occur in hospitals. People can carry it on their skin or in their noses with no symptoms and in this way they can infect others without knowing. Statistics shows that about 1 in 3 people carries some variety of the bacterium Staphylococcus aureus in the nose or skin, usually without harm.
About 95,000 serious infections with this type of bacteria occur in the United States each year, according to the CDC.
CDC studies agree that MRSA is more prevalent and potentially more serious when acquired in a hospital than when contracted outside, in the community. That is because people in a hospital are sicker.
Although the good-hygiene message is old and irrefutable, plenty of evidence suggests that people ignore it. A 2005 study found that while 91 percent of Americans say they always wash their hands after using a public rest room, only 83 percent actually did. Men were worse than women: 90 percent of women washed their hands while 75 percent of men did.
