Federal health officials reported Monday that at least two million Americans fall ill from antibiotic-resistant bacteria every year and that at least 23,000 die from those infections, putting a hard number on a growing public health threat. It was the first time that federal authorities quantified the effects of organisms that many antibiotics are powerless to fight.
The number of deaths is substantially lower than previous estimates, in part because researchers from the Centers for Disease Control and Prevention stripped out cases in which a drug-resistant infection was present but not necessarily the cause of death. Infectious disease doctors have long warned that antibiotic resistance — in which bacteria develop defenses against antibiotics used to kill them — threatens to return society to a time when people died from ordinary infections.
“They have come up with hard numbers where it has been only guesswork,” said Dr. Stuart B. Levy, a professor of microbiology at Tufts University and the president of the Alliance for the Prudent Use of Antibiotics. “This sets a baseline we can all believe in.”
In 2007, the C.D.C. estimated that about 100,000 people died every year of infections they developed while in hospitals. Most of those infections were believed to be resistant to some antibiotics, but not necessarily the most widely used ones. And it was unclear how many of the deaths were caused by the drug-resistant infections. Monday’s report quantifies that.
Dr. Steven L. Solomon, the director of the C.D.C.’s office of antimicrobial resistance, acknowledged that the report underestimated the numbers, but said that was by design. Researchers were instructed to be conservative and to base their calculations only on deaths that were a direct result of a drug-resistant bacterial infection.
“This is a floor,” Dr. Solomon said. “We wanted the cleanest number, the least subjective number.”