'Nightmare Bacteria' Cases Have Risen Fivefold

Infection rates from drug-resistant "nightmare bacteria" rose almost 70% between 2019 and 2023, according to a new report from Centers for Disease Control and Prevention scientists. Bacteria that are difficult to treat due to the so-called NDM gene primarily drove the increase, CDC researchers wrote in an article published Monday in the Annals of Internal Medicine. Only two antibiotics work against those infections, and the drugs are expensive and must be administered through an IV, researchers said.

• Bacteria with the gene were once considered exotic, linked to a small number of patients who received medical care overseas. Though the numbers are still small, the rate of US cases jumped more than fivefold in recent years, the researchers reported. "The rise of NDMs in the US is a grave danger and very worrisome," David Weiss, an Emory University infectious diseases researcher, tells the AP.

• It's likely many people are unrecognized carriers of the drug-resistant bacteria, which could lead to community spread, the CDC scientists said. That may play out in doctors' offices across the country, as infections long considered routine and easy to treat—like urinary tract infections—could become chronic problems, said Dr. Maroya Walters, one of the report's authors.
• Antimicrobial resistance occurs when germs such as bacteria and fungi gain the power to fight off the drugs designed to kill them. The misuse of antibiotics was a big reason for the rise—unfinished or unnecessary prescriptions that didn't kill the germs made them stronger.
• In recent years, the CDC has drawn attention to "nightmare bacteria" resistant to a wide range of antibiotics. That includes carbapenems, a class of antibiotics considered a last resort for treatment of serious infections.

• Researchers drew data from 29 states that do the necessary testing and reporting of carbapenem-resistant bacteria. They counted 4,341 cases of carbapenem-resistant bacterial infections from those states in 2023, with 1,831 of them the NDM variety. The researchers did not say how many of the infected people died.
• The rate of carbapenem-resistant infections rose from just under 2 per 100,000 people in 2019 to more than 3 per 100,000 in 2023—an increase of 69%. But the rate of NDM cases rose from around 0.25 to about 1.3—an increase of 460%, the authors said.
• The CDC's count is only a partial picture. Many states are not fully testing and reporting cases. Even in states that do, cases tend to be among hospital patients sick enough to warrant special testing. The CDC researchers did not have data from some of the most populous states, including California, Florida, New York, and Texas, which means the absolute number of US infections "is definitely underestimated," Dr. Jason Burnham, a Washington University researcher, tells the AP. Burnham believes the increased drug resistance is probably linked to the "huge surge in antibiotic use during the pandemic."