The overuse of antibiotics for patients in U.S. hospitals is contributing to the rise of so-called superbugs, according to a new study by the Centers for Disease Control and Prevention.
"This is a real public threat," said Dr. Arjun Srinivasan, associate director for health care-associated infection prevention programs at the CDC, who spoke to CNBC by phone.
The dangers from overprescribing antibiotics in hospitals are twofold, Srinivasan explained. First, patients may not need them and could suffer side effects. More important, however, is the danger of creating drug-resistant bacteria, known as superbugs, that are becoming increasingly commonplace.
"This is specific to the patients who get overprescribed," he said. "They run the risk of being susceptible to the superbugs at some point."
The CDC report cites a study from the Society for Healthcare Epidemiology of America and the Infectious Diseases Society of America that shows that antibiotics treatment can be incorrect in up to 50 percent of the instances in which antibiotics are prescribed.
Most prescriptions for antibiotics are written for urinary tract infections, lung infections and infections caused by drug-resistant staphylococcus bacteria, such as MRSA, said the CDC.
One-third of the prescriptions for vancomycin and one-third of antibiotics prescribed to treat urinary tract infections were ordered without proper testing or evaluation. Or they were prescribed for too long, the report stated.
The CDC's Srinivasan said that the problem comes from both sides of the hospital bed.
"People do have a tendency to want antibiotics when they are sick," he said. "And doctors are giving antibiotics as a result of feeling the pressure and naturally trying to get their patient well."
More than 2 million people a year in the U.S. get sick from the superbugs according to the CDC, resulting in 23,000 deaths.
Non-CDC estimates put the health-care costs associated with the drug-resistant bacteria at $20 billion a year. They cost another $35 billion in lost productivity.
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Srinivasan said the CDC report is a wake-up call for hospitals and their staff—one he said they are beginning to get.
"They are willing to work on this," he said." When we show them the data, they realized the situation. I do expect to see antibiotics used only when they are really necessary."
—By CNBC's Mark Koba. Follow him on Twitter @MarkKobaCNBC.