Drug-Resistant Shigella Bacteria on the Rise: A Growing Public Health Threat in the US and Beyond

The Centers for Disease Control and Prevention (CDC) has reported a significant rise in extensively drug-resistant (XDR) Shigella infections in the United States, with the proportion of isolates classified as XDR increasing from 0% in 2011 to 8.5% in 2023, based on an analysis of nearly 17,000 Shigella species isolates with resistance data.

This increase marks a concerning shift in the epidemiology of shigellosis, which historically affected primarily young children in daycare settings or travelers to regions with poor sanitation. National surveillance data now indicate that most XDR Shigella cases occur among adult men, with approximately one-third of patients requiring hospitalization.

XDR Shigella is defined as resistance to ampicillin, azithromycin, ceftriaxone, ciprofloxacin, and trimethoprim-sulfamethoxazole, leaving no Food and Drug Administration-approved oral treatment available for infected individuals. The bacteria spread easily through oral contact with fecal material, including during sexual activity, as well as through contaminated food and water.

Among patients with travel history, more than 80% reported no recent international travel, suggesting domestic transmission is driving the rise in cases. The CDC emphasizes that the high transmission potential of XDR Shigella strains, combined with the potential for resistance genes to spread to other enteric bacteria, makes this a growing public health threat.

Public health officials stress the importance of susceptibility testing and timely reporting of this nationally notifiable disease to support prevention efforts. Shigellosis, also known as bacillary dysentery, can cause prolonged bloody diarrhea, stomach pain, and fever, and remains a leading cause of diarrheal disease in pediatric patients worldwide, accounting for up to 40,000 deaths annually according to the National Library of Medicine.

The CDC’s findings, published in the Morbidity and Mortality Weekly Report on April 9, 2026, reflect a transformation in Shigella from a typically self-limiting infection that rarely required antibiotics into an emerging threat with limited treatment options, particularly affecting vulnerable populations.