Health officials in the United States have raised concerns over the growing spread of a drug-resistant form of Shigella, a bacterial infection that causes severe diarrhea and gastrointestinal illness.
According to a new report released by the Centers for Disease Control and Prevention, an extensively drug-resistant strain known as XDR Shigella has increased significantly over the past decade.
The agency reported that between 2011 and 2015, no cases of the resistant strain were identified. By 2023, however, XDR Shigella accounted for approximately 8.5 per cent of all reported infections in the country.
With an estimated 450,000 Shigella infections recorded annually in the United States, health experts warn that tens of thousands of patients could now be exposed to strains resistant to standard antibiotic treatment.
Limited Treatment Options Raise Concern
Public health officials say the resistant strain is particularly difficult to manage because it no longer responds to several commonly prescribed antibiotics.
The XDR Shigella strain has shown resistance to medications including ampicillin, azithromycin, ceftriaxone, ciprofloxacin, and trimethoprim-sulfamethoxazole, drugs traditionally used to treat bacterial gastrointestinal infections.
Health authorities also noted that there is currently no approved oral medication specifically available for treating XDR Shigella infections.
The CDC analysed more than 16,700 Shigella samples collected between 2011 and 2023. Researchers found that the first extensively drug-resistant case appeared in 2016, with cases steadily increasing since then.
More than one-third of patients infected with the resistant strain required hospitalization, according to the report.
Changing Infection Patterns
Health officials say the outbreak pattern has shifted in recent years.
While Shigella infections historically affected mostly children under five years old, recent data show that the majority of XDR Shigella cases are now occurring among adult men, with a median patient age of 41 years.
Investigators also found that most infected individuals had not recently travelled internationally, suggesting that transmission is now occurring largely within the United States.
How the Infection Spreads
Shigella spreads primarily through contact with contaminated food, water, or surfaces, as well as through person-to-person transmission involving poor hygiene or certain forms of sexual contact.
The CDC identified sexual transmission among men who have sex with men as one of the major factors contributing to the spread of the resistant strain.
Health experts added that individuals living with HIV may face greater health risks because of weaker immune systems and limited treatment options.
Symptoms and Prevention Measures
Symptoms of Shigella infection usually develop within one to two days after exposure and may include diarrhea, stomach cramps, fever, nausea, and, in severe cases, bloody stools.
Most infections improve within a week, although severe cases may last longer or require medical treatment.
Health authorities advised individuals experiencing prolonged diarrhea, dehydration, vomiting, high fever, or bloody stool to seek medical attention promptly.
To reduce infection risk, the CDC recommends regular handwashing, proper food and water hygiene, avoiding swallowing water while swimming, and maintaining safe hygiene practices.
Public health officials emphasized that early detection, stronger surveillance systems, and public awareness remain essential in controlling the spread of drug-resistant infections.