CDC Warns of Rising Drug-Resistant Shigella 'Superbug' in the U.S.

CDC Issues Warning About Rising Drug-Resistant Shigella Infections

The Centers for Disease Control and Prevention (CDC) has issued a warning about a growing threat: extensively drug-resistant (XDR) Shigella, a bacteria causing severe diarrhea and spreading rapidly in the United States. The CDC’s Morbidity and Mortality Weekly Report (MMWR), published on April 9, highlights the alarming rise in XDR Shigella cases, which are resistant to multiple antibiotics.

What Is Shigella and Why Is It Dangerous?

Shigella bacteria cause an infection known as shigellosis, characterized by symptoms such as:

• Severe diarrhea (often bloody)
• Fever
• Stomach cramps
• Nausea

Shigella is highly contagious and spreads easily through:

• Person-to-person contact
• Contaminated food or water
• Sexual activity with an infected person

XDR Shigella: A Growing Public Health Concern

Extensively drug-resistant (XDR) Shigella strains are resistant to five commonly prescribed antibiotics:

• Ampicillin
• Azithromycin
• Ceftriaxone
• Ciprofloxacin
• Trimethoprim-sulfamethoxazole

According to the CDC, no oral antibiotics approved by the FDA are currently effective against XDR Shigella infections.

Rising Infection Rates

The CDC analyzed 16,788 Shigella isolates collected between 2011 and 2023. Among these, 510 (3%) were identified as XDR. The proportion of XDR cases surged from 0% (2011–2015) to 8.5% in 2023.

Who Is Most Affected?

The CDC report reveals a shift in the epidemiology of Shigella infections:

• Previously, outbreaks primarily affected children.
• Now, XDR Shigella cases are most common in adult males (average age: 41).
• Most infections are domestically acquired—76.2% of cases reported no recent domestic travel, and 82.4% reported no recent international travel.

Expert Insights on Antibiotic Resistance

“Antibiotic resistance is a global issue because antibiotics are overused and used inappropriately around the world. In the U.S., clinicians and public health officials have worked hard to become good stewards of antibiotics, using them carefully.”

How to Prevent Shigella Infections

To reduce the risk of Shigella transmission, the CDC recommends:

• Frequent handwashing with soap and water, especially after using the toilet, changing diapers, or before preparing food.
• Avoiding swimming in contaminated water.
• Ensuring safe food handling and proper cooking.
• Practicing safe sexual behaviors to prevent fecal-oral transmission.

What’s Next? CDC Calls for Stronger Surveillance

The CDC notes that with the rising prevalence of XDR Shigella, enhanced surveillance and infection control measures are critical to preventing further spread. Public health officials urge healthcare providers to report suspected cases promptly and to follow updated guidelines for treatment and prevention.

Key Takeaways

• XDR Shigella infections are increasing in the U.S., with 8.5% of cases in 2023 resistant to multiple antibiotics.
• No oral FDA-approved antibiotics are currently effective against XDR Shigella.
• Most cases are domestically acquired, primarily affecting adult males.
• Prevention relies on hand hygiene, safe food handling, and avoiding high-risk behaviors.