Published March 08, 2023
The CDC is warning about a rise in cases of drug-resistant Shigella bacteria. Shigella is one of the most common causes of gastroenteritis (stomach flu), along with certain strains of E. coli and Norovirus, and it usually appears in Summer. However, it’s unclear why a strain resistant to antibiotic treatment is circulating now.
Shigella is highly contagious and is spread through the fecal, oral route. That means people can become infected through contaminated food or water, by touching infected surfaces or hands of infected people. There are also reports of cases spread during sexual encounters. Common symptoms include:
Yale New Haven Hospital Infectious Disease specialist Scott Roberts, MD, Associate Medical Director of Infection Prevention for Yale School of Medicine, says most people can recover on their own with rest and proper hydration. Older patients, those who are immunocompromised, and kids under 5 are at a higher risk of more severe infection.
At-risk patients may benefit from antibiotic treatment, usually with ciprofloxacin or azithromycin. Dr. Roberts says if patients present with a drug-resistant Shigella infection in the hospital, there are other antibiotics that may be beneficial. However, the overall trend of seeing drug-resistant bugs is concerning.
“We as infectious disease clinicians do our best to limit and be judicious on antibiotic use because we can induce resistance in these bugs and we generally do a good job of that in the United States,” Dr. Roberts said.
Unfortunately, antibiotics are more widely used in other countries, some even offered over the counter.
Dr. Roberts points to antibiotic overuse and misuse as two of the biggest factors contributing to bugs developing drug resistance over time. While rare, there are some bugs that have become resistant to all classes of antibiotics. Recently, a nearly fully drug resistant strain of gonorrhea was identified in Massachusetts.
While proper prescribing practices falls on clinicians, there are other factors out of their hands. The Candida auris fungus, which was only discovered in 2009, is resistant to all three major classes of antifungal medications. Climate change is likely to blame.
“This species has been shown to survive at much higher temperatures,” Dr. Roberts said. “With climate change we may see increasing evolution of bacteria and other pathogens that can affect us.”
Sound a little too familiar? Perhaps the plot of a popular video game turned hit show? The villain in “The Last of Us” is based off Ophiocordyceps unilateralis, or cordyceps, a fungus that infects insects in the real world. Dr. Roberts says the likelihood of it jumping to humans like it does on the show, is “exceedingly unlikely” because cordyceps can’t even infect certain types of ants and usually requires thousands of years of evolution to cross species.
The best way for patients to protect themselves from Shigella and all drug-resistant bugs is to prevent infection in the first place. Avoid close contact with those who are sick, disinfect commonly touched surfaces with bleach and wash hands with soap and water. While hand hygiene doesn’t make an interesting show hero, it’s been proven time and again to be one of our best defenses against illness.
