The CDC issued the warning Feb. 24 about the rise in the problematic infections. Most of them have been seen in men who have sex with men, but a small number have also occurred in women and in young children.
The bacteria can be spread in a variety of ways, including changing the diaper of an infected baby, touching your mouth when the bacteria are on your hands, eating or drinking contaminated food or water, or through sexual contact. It’s easily transmitted because just a tiny amount of the bacteria is enough to make someone sick.
Shigella infection causes diarrhea that can be bloody. Other symptoms are a fever, belly cramping, and the feeling that you have to poop but your bowels are already empty. Most people recover on their own with rest and fluids, and severe cases can need antibiotic treatment. But strains of the bacteria that are resistant to treatment are on the rise.
Between 2015 and 2022, cases of antibiotic-resistant Shigella infection rose from 0% to 5% of all Shigella cases in the United States. One analysis showed that 82% of cases were in men, 13% in women, and 5% in children. A small sample of affected people provided information about their sexual activity, and 88% of them reported male-to-male sexual contact.
People at increased risk of infections are young children, people who are homeless, international travelers, people who have weakened immune systems, people living with HIV, and men who have sex with men.
The CDC asked health care workers to be on the lookout for these infections and report them.
A version of this article first appeared on WebMD.com.