CDC officials are sounding the alarm about a rise in drug-resistant Shigella infections across the United States, based on a large surveillance review. Researchers tested more than 16,000 samples and found a clear uptick in versions of the bacteria that no longer respond to common antibiotics. The trend has serious treatment implications because oral options are limited and some patients end up hospitalized.
Shigella is a gram-negative bacterium that causes shigellosis, a diarrheal illness that can be severe and sometimes bloody. Symptoms typically appear within a day or two of exposure and can range from mild stomach upset to prolonged, painful diarrhea. While many recover in a week, certain groups face greater risk of complications and more severe disease.
DEADLY ‘SUPERBUG’ IS SPREADING ACROSS US AS DRUG RESISTANCE GROWS, RESEARCHERS WARN The review compared strains collected over more than a decade and tracked how often they resisted standard treatments. The rise in resistance was steady, making what used to be straightforward infections harder to manage for clinicians.
Scientists screened over 16,000 Shigella isolates to see which ones would not be susceptible to front-line drugs. Drug resistance was defined as a lack of response to ampicillin, azithromycin, ceftriaxone, ciprofloxacin or trimethoprim-sulfamethoxazole, which are commonly used to treat bacterial diarrheal infections. Alarmingly, there are currently no FDA-approved oral antimicrobials that reliably treat these highly resistant cases.
The data show that highly drug-resistant Shigella was essentially absent in 2011 but had grown to roughly 8.5 percent of infections by 2023. The shift matters because when first-line pills fail, patients may need intravenous therapy or more intensive care. That change also places more strain on hospitals and public health systems when outbreaks occur.
Most of the reported cases were adult men, accounting for about 86 percent of the patients, with a median age around 41 years. Among those who provided travel histories, more than four out of five had not recently left the country, which points to domestic transmission rather than importation. Roughly one in three infected people required hospital care, illustrating the potential severity of resistant infections.
Among patients who shared HIV status, nearly half were living with HIV, a detail clinicians flagged as important when considering who may be at higher risk. The researchers also cautioned that surveillance systems may not capture every domestic case and that key variables were missing for some patients. Because of these gaps, the findings might not apply equally to every community or setting across the country.
Typical signs of shigellosis include diarrhea that can be prolonged or bloody, fever and abdominal pain, all usually starting within 24 to 48 hours after exposure. Some people infected with Shigella show no symptoms but can still spread the germ to others. Symptoms most often last five to seven days, although a subset of patients may feel unwell for several weeks.
In rare cases, infected individuals can develop complications such as reactive arthritis, bloodstream infections, seizures or hemolytic-uremic syndrome, a serious condition that damages blood vessels in the kidneys. These complications are uncommon but can be life-changing when they occur, especially in people with weakened immune systems. Awareness and early medical attention help reduce the chance of these outcomes.
Shigella spreads easily from stool to hands to food or surfaces, making hygiene key to prevention. Routine activities like changing diapers or caring for an ill person can pass the germ if hands are not washed thoroughly, and contaminated surfaces or foods can also be sources. People should avoid sexual contact with a partner who has been diagnosed, and anyone with symptoms should seek medical care and remain at home until they are no longer contagious.
Public health officials urge continued surveillance, timely reporting and clear communication to curb the spread of resistant strains. Clinicians need updated guidance for testing and appropriate treatment choices when resistance is suspected. If you have symptoms, contact a healthcare provider so they can test, advise on treatment and help prevent spread to others.
