More than 2 million Americans develop antibiotic-resistant infections each year and about 23,000 die as a result, according to a new report from the U.S. Centers for Disease Control and Prevention.
Government health officials fear those numbers, which are conservative estimates, could worsen as overuse and misuse of antibiotics cause more bacteria to develop resistance to the drugs. Without a major effort to preserve the current supply of antibiotics and to develop new ones, they say future generations will be ill-equipped to fight off the deadly superbugs.
"If we're not careful, the medicine chest will be empty when we go there to look for a lifesaving antibiotic for someone with a deadly infection," said Dr. Thomas Frieden, director of the CDC. "But if we act now, we can preserve these medications while we continue to work on development of new medications."
The new report, "Antibiotic Threats in the United States, 2013," is the first comprehensive analysis of the nation's 18 most serious drug-resistant bacterial threats. The CDC, for the first time, has categorized the bacteria and the threat they pose as "urgent," "serious" and "concerning."
Topping the list of the three "urgent" threats is carbapenem-resistant Enterobacteriaceae, or CRE. Known as the "nightmare bacteria" because of its high mortality rate, CRE is resistant to nearly all antibiotics and spreads its drug resistance to other bacteria that otherwise would be vulnerable to vaccines.
Patients at long-term or complex medical care facilities and nursing homes are at the greatest risk for CRE infection, which is spread mainly by dirty hands. Medical devices like ventilators and catheters increase the risk of infection because they allow the bacteria to get deep into a patient's body.
CRE infects about 9,300 people a year and kills an estimated 610, the CDC estimates. A strain of CRE killed seven patients in 2011 at the National Institutes of Health Clinical Center in Bethesda, Md.
Another "urgent" bacterial threat is Clostridium difficile, which attacks patients mainly in health care settings. Although not yet significantly resistant to the drugs that treat it, C-diff is a diarrheal infection usually associated with antibiotic use. It infects about 250,000 people and kills at least 14,000 annually.
Drug-resistant gonorrhea is the last "urgent" bacterial threat. The sexually transmitted disease infects nearly 250,000 people each year but kills less than five, according to CDC estimates.
The 12 bacterial threats rated as "serious" include the superbug Methicillin-resistant Staphylococcus aureus , or MRSA, which infects 80,000 people a year and kills 11,000; drug-resistant Streptococcus pneumoniae, which infects 1.2 million people annually and kills about 7,000; and drug-resistant Candida, a fungus that is showing increasing resistance to antibiotics. Candida attacks hospitalized patients and infects about 3,400 people a year, killing about 220.
To fight antibiotic resistance, the CDC calls for better preventative measures like immunizations, safer food preparation and more hand-washing; improved tracking of antibiotic-resistant infections; greater development of new antibiotics and diagnostic tests; and more conservative use of antibiotics.
The CDC estimates that up to half of all prescribed antibiotics are unnecessary. The agency stresses that every time a patient takes an antibiotic they don't need, they increase their risk of developing a resistant infection in the future.
"What we hope is that this report will prioritize and propel both research and implementation of efforts to prevent and stop the spread of drug-resistant microbes," Frieden said.
The CDC estimates that antibiotic resistance costs the U.S. economy up to $20 billion a year in excess health care costs and about $35 billion in lost productivity.
By Tony Pugh
McClatchy Washington Bureau