A recent CDC analysis, published in Annals of Internal Medicine, documents a sharp rise in dangerous antibiotic-resistant bacteria in the United States between 2019 and 2023. The report focuses on carbapenem-resistant Enterobacterales (CRE) — a group that includes E. coli and Klebsiella pneumoniae — which are resistant to carbapenems, a last-resort class of broad-spectrum antibiotics. A subset called carbapenemase-producing CRE (CP-CRE) is especially worrisome because these bacteria make enzymes that destroy carbapenems, leaving few effective treatment options.
The study identifies New Delhi metallo-β-lactamase–producing CRE (NDM-CRE) as the main driver of the increase. NDM-CRE can be resistant even to some newer drugs developed for carbapenem-resistant infections. Across surveillance networks in 29 states, covering more than one-third of the U.S. population, reported CP-CRE clinical cultures rose by 69% from 2019 to 2023, while NDM-CRE incidence increased by 461%.
CP-CRE and NDM-CRE can cause serious infections — including pneumonia, bloodstream infections, wound infections, meningitis, and urinary tract infections — and are hard to treat. A separate CDC estimate attributed about 12,700 infections and 1,100 deaths to CRE in 2020. NDM-CRE are also capable of transferring resistance genes to other bacteria, accelerating the spread of resistance across species.
Transmission occurs mainly in hospitals and other healthcare settings. These infections are concentrated among very ill patients and are less common in the general community. People at highest risk include those on mechanical ventilators, people with invasive medical devices such as urinary or intravenous catheters, those receiving prolonged antibiotic courses, and individuals with weakened immune systems.
Symptoms depend on the infection site; there are no signs unique to CRE. Presentations may look like typical urinary tract infections, pneumonia or other respiratory infections, bloodstream infections, wound infections, or meningitis. Early detection matters because treatment must be matched to the specific carbapenemase type and tailored to patient factors such as kidney or liver function and drug allergies.
CRE spreads through direct contact with infected or colonized people, contaminated surfaces, and medical equipment. Animal-to-human transmission has been reported but is uncommon. Both people and animals can be colonized without symptoms and still transmit the bacteria.
Preventing CRE in healthcare settings requires active surveillance, strict cleaning and disinfection of surfaces and instruments, and rigorous hand hygiene. Visitors and caregivers should practice careful handwashing when visiting hospitals and long-term care facilities, especially around immunocompromised or elderly patients.
More broadly, this surge is part of the larger antimicrobial resistance (AMR) crisis, sometimes called a silent pandemic. A 2024 Lancet forecast projected that AMR could cause as many as 39 million deaths by 2050, with about 1.91 million deaths in that year alone. Public health agencies including the CDC and WHO promote antimicrobial stewardship programs to improve antibiotic prescribing and reduce overuse. Progress in stewardship has come from interdisciplinary teams, better diagnostic tools, and ongoing research, all aimed at preserving treatment options and slowing the spread of resistance.
