A common stomach bug is becoming harder to treat, the Centers for Disease Control and Prevention says, adding to the growing list of infections that can withstand several lines of antibiotics.
A CDC report released this month found “extensively drug-resistant” bacteria caused about 9% of shigellosis cases in 2023, up from 0% in 2011. Symptoms of shigellosis include fever, stomach pain and diarrhea that can be bloody and last for days.
The report looked at nearly 17,000 bacterial samples over that 12-year span.
Shigellosis generally resolves on its own, but more than a third of the extensively drug-resistant cases in the agency’s report resulted in hospitalization. People with weakened immune systems are more vulnerable to severe shigellosis, which can cause dehydration, kidney damage and infections of the bloodstream.
There are no oral antibiotics approved by the federal Food and Drug Administration to treat these more challenging infections, meaning doctors often must resort to potent intravenous antibiotics. No deaths were reported by the CDC, though the disease can be fatal without proper care.
Shigellosis, caused by the shigella bacterium, has historically been most prevalent among kids, but people of all ages can get the disease. In the CDC report, 86% of the extensively drug-resistant cases were among men with a median age of 41.
The disease is highly contagious and spreads when fecal pathogens enter the mouth.
“It’s easily transmitted,” said Dr. Nitin Bhanot, an infectious disease specialist at Allegheny Health Network. “You could have a few bugs on your hand … and that could really cause infection really fast.”
Transmission often happens when changing a baby’s diaper, eating food prepared without proper sanitation measures and during sexual contact. Men who have sex with men are especially likely to contract shigellosis, as are people who have recently traveled.
Hand-washing is key to prevention. Anyone infected should also avoid sex or making food for others while they’re sick and immediately after.
Extensively drug resistant cases aren’t necessarily more severe, and there’s nothing to suggest their rise is contributing to a higher overall infection count, at least in Pennsylvania. The state Department of Health logged 367 shigellosis cases last year, down significantly from 2023 and 2024.
But they can be harder to get a handle on. The CDC defined these cases are not responding to three first-line and two second-line antibiotics. Doctors can determine which medications might work through bacteria cultures or molecular testing. Results can take a few days to come back.
Antibiotic resistance is seen by public health experts as an urgent and rising threat. When antibiotics are given, more resilient bacteria may survive and multiply. They also have a chance to mutate and develop even stronger defenses. Overuse of antibiotics has accelerated this process, limiting the effectiveness of these drugs when they’re truly needed.
More than 2.8 million drug-resistant infections occur in the U.S. each year, and 35,000 people die as a result, according to the CDC. This latest report further fuels concerns those figures could continue to climb.
“It is part of a trend that we have observed since penicillin was first put into use, and that is a persistent march into microbial resistance,” said Dr. Graham Snyder, medical director of infection prevention and hospital epidemiology at UPMC.