The United States has been hit by infections from drug-resistant, nightmare bacteria, which increased by nearly 70% between 2019 and 2023.
Centers for Disease Control and Prevention study shows particularly worrying spikes in bacteria carrying the NDM gene that renders most antibiotics ineffective.
The research, published on Monday, September 22, 2025, in the Annals of Internal Medicine journal, found that carbapenem-resistant infections rose from 2 to 3.2 cases per 100,000 people during the four-year period.
More alarmingly, infections involving the NDM gene, which makes bacteria resistant to all but two expensive, intravenously-administered antibiotics, surged by 460%, from 0.25 to 1.35 cases per 100,000 people.
"The rise of NDMs in the U.S. is a grave danger and very worrisome," stated David Weiss, an Emory University infectious diseases researcher, highlighting the limited treatment options available for these infections.
The study analyzed data from 29 states from the U.S. that conduct specialized testing for carbapenem-resistant bacteria, identifying 4,341 cases in 2023 with 1,831 involving the NDM variety.
Researchers noted that the actual number of infections is likely significantly higher since many states, including populous ones like California, Florida, New York and Texas, do not fully test or report cases.
The U.S. public health agency spokeswoman said: "The misuse of antibiotics remains a significant driver of antimicrobial resistance, and we continue to work with healthcare providers to promote appropriate antibiotic stewardship."
CDC scientists warned that many Americans may be unrecognized carriers of these drug-resistant bacteria, potentially leading to community spread that could transform routine infections like urinary tract infections into chronic, untreatable conditions.