The most common infections are pneumonia (22 percent), surgical site infections (22 percent), gastrointestinal infections (17 percent), urinary tract infections (13 percent), and bloodstream infections (10 percent), the agency reported in the study, published Wednesday in the New England Journal of Medicine.
When coupled with the growing risks posed by of antibiotic resistant bacteria, the prevalence of hospital-acquired infections remains a serious problem for care-givers, one that the CDC is continuing to battle on a state-by-state and even hospital-by-hospital basis, Bell said in a news conference Wednesday afternoon.
"Sooner or later everyone is likely to become a patient somewhere," he said. "We go to the hospital hoping to become better, and mostly we do, but not always."
Atop the list of pathogens acquired in hospitals is the bacterium clostridium difficile (commonly know as c. diff), which can cause gastroenterological illnesses so severe that removal of a patient's colon is sometimes required, Bell said. It was responsible for 12.1 percent of the infections turned up by the survey. Also common was methicillin-resistant staphylococcus aureus (MRSA), a staph infection that has become resistant to common antibiotics.
Such infections -- rather than ones associated with devices such as central catheters, urinary catheters and ventilators, comprised the majority of the health-care-related infections revealed by the survey. Indeed, Bell said, the rate of infections from "central lines" that are placed into patients' major blood vessels has been cut nearly in half since 2008, and the infection rate after surgery has declined by 20 percent in the same time.
But urinary tract infections, which are not as dangerous, remain persistent, he said.
About 34 million people were admitted to U.S. acute care hospitals in 2012, according to the study, which did not look at other in-patient settings such as nursing homes. The infection rate declined when compared with the results tallied by the CDC in 2007, but those were based on historical data rather than a survey, Bell said.
At the news conference, Victoria Nahum, executive director of the Safe Care Campaign, urged hospital patients to insist on "compulsive hand hygiene" and other best practices by their care-givers, including physicians, and visitors. That may mean patients will have to overcome the fear of questioning doctors about their hygiene while hospitalized, or have a relative or friend do it for them, she and Bell said.
Nahum's son, Joshua, died in 2006 at age 27 of a health-care-related infection just two months after two other members of her family suffered complications from similar infections.
President Obama's proposed fiscal 2015 budget includes money to battle antibiotic resistance. Bell said the continuing effort will require hospitals to remain judicious about the use of antibiotics in order to gradually lessen resistance to them, in the hope that some will become effective again. He said the problem of widespread resistance also is prompting new approaches to controlling bacteria.
"I remain extremely cautious regarding the growing threat of antibiotic resistance," Nahum said.