The continued overuse of antibiotics is associated with a majority of the nearly half million cases of Clostridium difficile infection that occurred in 2011, which in turn were linked to an estimated 29,000 deaths, federal health officials said Wednesday.
“C. difficile infections cause immense suffering and death for thousands of Americans each year,” Centers for Disease Control and Prevention Director Dr. Thomas Frieden said in a released statement. “These infections can be prevented by improving antibiotic prescribing and by improving infection control in the healthcare system.”
A study by the CDC published online Wednesday in the New England Journal of Medicine found that of the estimated 453,000 cases of C. difficile infection that occurred, 66% were associated with a healthcare setting.
However, only 24% were found to have contracted the bacteria during their hospitalization, suggesting many patients develop illness after they have been discharged.
The study found patients taking antibiotics were most at risk for developing C. difficile infections, which causes severe diarrhea when good bacteria that protects against infection is wiped out by antibiotic treatment.
More than half of all hospitalized patients will get an antibiotic at some point during their stay, but a growing amount of evidence over the past decade has estimated that as much as half of antibiotics prescribed in hospitals may have been unnecessary. Such overprescribing has been responsible for a rise in drug-resistant superbugs, experts contend.
A CDC report released last year called for a 30% reduction in prescriptions of the kind of antibiotics most likely to cause C. difficile infections, a change that could reduce the spread of the disease by 26%.
“Antibiotics are clearly driving this whole problem,” said Dr. Clifford McDonald, CDC senior advisor for science and integrity, during a call with reporters Wednesday.
The majority of infections occur in patients 65 and older, accounting for one of every three cases, according to the study. More than 100,000 cases were found to have occurred in nursing homes.
The latest study is the largest estimate for incidents of C. difficile, which was previously thought to occur in as many 250,000 patients a year. The infection has become the most common cause of healthcare-acquired infections, costing up to $4.8 billion annually in health costs.
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