648,000 Got Hospital-Related Infections in 2011
Specific source of dangerous germs still unclear in about half of cases
By Dennis Thompson
WEDNESDAY, March 26, 2014 (HealthDay News) -- About one of every 25 U.S. hospital patients contracts an infection during their stay, and doctors can't say for certain why half those infections occur, according to a new study by the U.S. Centers for Disease Control and Prevention.
Researchers estimate that in 2011 about 648,000 Americans developed an infection while hospitalized, or about 4 percent of all inpatients. About 75,000 of those patients died while in the hospital.
About half of the infections resulted from surgery or through use of a medical device such as a ventilator or a catheter, the study reports. These causes of hospital infection are well known and efforts are underway to combat them.
The other half are infections with no clear cause, researchers said.
"This finding should expand the public health focus to include these other types of infections, identifying patients at risk and developing effective prevention measures," the study's authors conclude.
For example, pneumonia is the most common infection associated with a hospital stay, the new study reports, accounting for about 22 percent of all health care-related infections.
But only half of those hospital pneumonia cases could be linked to a patient placed on a ventilator, said Dr. Mike Bell, deputy director of the CDC's division of healthcare quality promotion. Ventilator-associated pneumonia is a common occurrence with a known set of recommended steps that can be taken to prevent its spread.
"That tells me these pneumonias happening outside the ICU need to be investigated," he said. "This study points us toward the things we need to tackle next."
Besides pneumonia, other common infections that occur in hospitals include surgical site infections (22 percent), gastrointestinal infections (17 percent), urinary tract infections (13 percent) and bloodstream infections (10 percent), according to the CDC report published in the March 27 New England Journal of Medicine.
Clostridium difficile is the most common germ spread during a hospital stay, accounting for 12 percent of all infections, the study found. About seven of 10 gastrointestinal infections in the hospital involve C. difficile.
C. difficile can cause deadly diarrhea and results from antibiotic overuse. The germ infests a person's colon after antibiotics have wiped out the healthy bacteria that normally resides in their gut.
"This is not just the nuisance diarrhea it used to be 12 years ago," Bell said, noting that the germ produces a toxin that has grown more powerful over time. "That toxin chews up the colon to such an extent that people have to have their colons removed to save their lives."
These other germs most commonly spread in hospitals all have strains that are antibiotic resistant:
- Staphylococcus aureus, including MRSA (11 percent)
- Klebsiella (10 percent)
- E. coli (9 percent)
- Enterococcus (9 percent)