What to know about spiking "nightmare bacteria" and CDC's new warning
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Infection rates for a drug-resistant "nightmare bacteria" are rising, per a new report from the CDC.
Why it matters: Antibiotic-resistant bacteria and fungi have caused millions of infections and thousands of deaths annually in the United States.
- Recently, the CDC has pointed to "nightmare bacteria" resistant to antibiotics as a major potential danger. These are largely hospital-acquired infections.
- Specifically, there's been concern about a group of bacteria called Enterobacterales that resist antibiotic treatments — specifically carbapenems, a type of antibiotic often used in worst-case scenarios for serious infections.
- The carbapenem-resistant Enterobacterales (CRE) were labeled "nightmare bacteria" by former CDC director Tom Frieden in 2013.
Rise in "nightmare bacteria" cases
Driving the news: CDC researchers wrote Tuesday in the Annals of Internal Medicine that infections from bacteria resistant to powerful antibiotics are spiking.
- The resistance is mainly driven by the "NDM" gene, which creates an enzyme that destroys antibiotics.
- The study analyzed cases reported by 29 states, but not California, Florida, New York or Texas.
By the numbers: The rate of carbapenem-resistant infections jumped from under 2 per 100,000 in 2019 to more than 3 per 100,000 in 2023, an approximate 69% jump, the researchers said.
- The rate of CRE infections with the NDM gene jumped by 461%, the study said.
- In 2019, 24 states saw a total of 2,267 cases. In 2023, 29 states saw 4,341 cases total, the report said.
Threat of "nightmare bacteria"
Threat level: "They pose a triple threat," Frieden said — high mortality rates, resistance to drugs and easy spread to other bacteria.
- It's likely people wouldn't recognize they're carrying the bacteria, igniting community spread, the CDC scientists said, per AP.
- In 2020, "CRE" infections caused about 12,700 infections and 1,100 deaths, per Scientific American.
- A September study in eClinical Medicine found about one-third of hospital infections were antimicrobial-resistant.
"Nightmare bacteria" symptoms
The CDC lists the symptoms and signs of CRE infection, including:
- Pneumonia,
- Bloodstream infections,
- UTIs,
- Wound infections and
- Meningitis.
Patients most at risk are those in health care settings, especially those using ventilators, urinary catheters or vein catheters, the CDC says.
- Others at risk include patients on long-term courses of antibiotics and with weakened immune systems, per the CDC.
How "nightmare bacteria" spreads
CRE bacteria spread through contact with dirty hands, wounds or feces — and from medical equipment, per the CDC.
- There have been rare reports of spread between animals and humans.
- Some people can carry the bacteria without symptoms or illness.
Go deeper: More Americans die from superbugs than previously estimated, CDC says
