CDC Investigates First U.S. Outbreak of XDR Salmonella with NDM-1 Gene Linked to Moringa Capsules

The CDC is investigating a multistate outbreak of extensively drug-resistant Salmonella infections linked to certain lots of moringa powder capsules. The outbreak reports seven cases in seven states, with three hospitalizations but no deaths.

This is the first documented outbreak of Salmonella with an NDM-1 gene in the United States. The strain of Salmonella Newport detected carries an NDM-1 carbapenemase gene and shows unusual and highly concerning antimicrobial resistance.

The moringa powder capsules are sold under the Rosabella brand and are distributed by Ambrosia Brands LLC. The capsules are packaged in white plastic bottles with a green label. They are sold primarily online via the company's website, as well as Amazon, eBay, TikTok Shop and Shein.

The firm agreed to recall bottles with 52 lot codes, all of which have expiration dates in 2027. Lot codes are visible on the bottom of capsule bottles, above the expiration date. A list of the lot codes affected by the recall is available on the FDA website.

Whole genome sequencing analysis of clinical samples from ill people in the outbreak predicts that most of the bacteria are extensively drug resistant. Antimicrobial susceptibility testing to confirm resistance is currently underway.

The Salmonella strain associated with this outbreak is resistant to all first-line and alternative antibiotics typically recommended for Salmonella infections. The strain also may be resistant to multiple beta-lactam antibiotics, such as meropenem and other carbapenems. Infection with this strain may not be treatable with amoxicillin-clavulanic acid, ampicillin, azithromycin, ceftriaxone, ciprofloxacin, meropenem, and trimethoprim-sulfamethoxazole.

Clinical breakpoints to determine resistance have not been established for azithromycin, but most isolates carry a macrolide resistance gene that typically correlates with an elevated minimum inhibitory concentration greater than 32 µg/ml.

Most people with Salmonella infection recover without antibiotics. If antibiotics are needed, infections with this strain may not be treatable with commonly recommended antibiotics and may require a different antibiotic choice.

When possible, the CDC recommends antibiotic treatment be tailored to antimicrobial susceptibility testing. Consultation with an infectious disease specialist may be necessary for complicated or extensively drug-resistant cases.

For uncomplicated infection, existing information on oral fosfomycin use for multidrug-resistant urinary tract infections or gastrointestinal infections may be considered. Isolates from this outbreak strain do not show predicted resistance to fosfomycin. For complicated or invasive infection, guidance on the management of infections caused by NDM-producing Enterobacterales discusses treatment approaches, such as cefiderocol monotherapy or aztreonam-avibactam.

The CDC advised anyone who has affected capsules not to consume them; instead, the capsules should be thrown out or returned. Items or surfaces that may have touched the affected capsules should be washed thoroughly. Anyone who experiences severe symptoms like high fever, dehydration, diarrhea or vomiting is urged to call their health care professional.

The CDC announced in January it was investigating a Salmonella outbreak linked to dietary supplements that contained moringa leaf powder. The two outbreaks are unrelated.