US data show ‘alarming’ increase in multidrug-resistance gene

News brief

CRE bacteria under the microscope — Stephanie Rossow / CDC

US surveillance data show a dramatic rise in the incidence of a particularly worrisome form of multidrug-resistant bacteria in hospital patients, researchers from the Centers for Disease Control and Prevention (CDC) reported yesterday in Emerging Infectious Diseases.

The data are from the CDC’s Emerging Infections Program (EIP) Multi-site Gram-negative Surveillance Initiative, which collects and analyzes bacterial isolates from 10 locations around the country to monitor the incidence of carbapenem-resistant Enterobacterales (CRE). Infections caused by CRE—which includes carbapenem-resistant strains of Escherichia coli, Klebsiella pneumoniae, and Enterobacter—are among the superbugs the CDC keeps track of because they are resistant to multiple classes of antibiotics and are a major concern for hospital patients.

In 2022, an estimated 13,387 CRE infections occurred in US hospital patients.

The isolates were all tested for the presence of carbapenemase genes, which confer broad resistance to beta-lactam antibiotics and can be shared among bacterial species. Of the 1,288 carbapenemase-producing CRE identified from 2016 to 2023, bla_KPC was the most common carbapenemase gene detected (79%), followed by bla_NDM(20.6%), bla_OXA-48-like (7.5%), bla_IMP (0.6%), and bla_VIM (0.5%).

But the proportion of isolates carrying bla_NDM, which was once rare in the United States, rose from 5.4% in 2016 to 39.8% in 2023. The increase was seen most prominently in E coli, with bla_NDM representing 73% of all carbapenemase-producing E coli in 2023.

“The increase of bla_NDM is alarming given that NDM-producing CRE are more resistant than other CRE isolates,” the study authors wrote, adding that they are resistant to some of the newer beta-lactam combination antibiotics that have been developed specifically for CRE infections, which further limits treatment options.

Clinicians should be on the lookout

The researchers say further investigation is needed to see if the increase is occurring nationwide, to compare the characteristics of patients infected with NDM-producing CRE versus those with bla_KPC, and to determine whether the increase is related to clonal expansion.

“Our findings should alert clinicians to the increase in bla_NDM and encourage mechanism testing in clinical laboratories,” they wrote.

Multistate Salmonella outbreak tied to moringa supplements tops 100 cases, leads to new recall

News brief

Jim Wappes

**Recalled moringa capsules.** (CDC photo)

After reopening an investigation into a Salmonella outbreak tied to moringa leaf powder, the Centers for Disease Control and Prevention (CDC) yesterday confirmed 22 new cases in four newly affected states and implicated another product.

The new cases and states increase the outbreak total to 119 infections in 36 states. The CDC also confirmed six new outbreak-related hospitalizations, bringing hospital cases to 32. No deaths have been reported, however.

“Epidemiologic information shows some lots of TNVitamins Moringa Capsules may be making people sick now,” the CDC said. “CDC and FDA [Food and Drug Administration] continue to work to identify if there are other products causing illness in this outbreak.”

The CDC said Total Nutrition, Inc, has recalled two brands of moringa capsules: TNVitamins Ultra Potent Complete Green Superfood Moringa 10,000 milligrams [mg], and Doctor’s Pride Complete Green Superfood Ultra Potent Moringa 10,000 mg (see photo above).

This is the third recall in this outbreak. On January 15, Superfoods, Inc., recalled all Live it Up Super Greens supplement powders. On January 28, Why Not Natural recalled Why Not Natural Pure Organic Moringa Green Superfood capsules.

2 Salmonella strains

The multistate outbreak involves both the Typhimurium and Newport strains of Salmonella. Illness-onset dates in the outbreak range from August 22, 2025, to April 26, 2026. Patients range in age from less than 1 year to 81 years, with a median age of 45. More than half are male (57%), and nearly all are White (92%).

“The true number of sick people in this outbreak is likely much higher than the number reported, and this outbreak may not be limited to the states with known illnesses,” the CDC said. This is because many people recover without medical care and are not tested for Salmonella. In addition, recent illnesses may not yet be reported.”

The true number of sick people in this outbreak is likely much higher than the number reported.

Wisconsin has the most cases (16), followed by Minnesota (nine).

The CDC also reported yesterday a new Salmonella Typhimurium outbreak with 18 cases and seven hospitalizations in 14 states. That separate outbreak is linked to Mogo brand moringa capsules, which have also been recalled.