Apparently, “sexually transmitted diarrhea” is a phrase we all have to know now.
If you saw that headline and immediately had questions, fair. How does that even happen? Is this some new infection? And does “drug-resistant superbug” mean doctors can’t do anything?
The infection behind the headlines is called shigellosis. It’s caused by Shigella bacteria, and yes, it can spread through sex. It can also spread through contaminated food, water, hands, and surfaces. Sex is one route, not a requirement.
The antibiotic-resistance concern is real. But there’s some important context between a scary headline and what the research actually shows.
How do you catch Shigella through sex?
Here’s the unglamorous explanation: Shigella spreads when someone swallows bacteria from an infected person’s stool.
That can happen during sexual activity involving stool exposure, including when contaminated fingers reach someone’s mouth. You don’t have to see contamination for it to matter.
The CDC says gay and bisexual men and other men who have sex with men have a higher risk than other adults. It also explicitly says the risk exists with any sexual activity involving stool exposure.
That matters. This is about how bacteria spread, and anyone can get shigellosis.
Outside of sex, exposure can happen while caring for a sick child, eating contaminated food, or swallowing contaminated swimming water.
What’s actually rising?
An April 9, 2026, CDC report examined Shigella samples collected from 2011 through October 2023.
Among samples with resistance data, the proportion classified as extensively drug-resistant rose from zero in 2011–2015 to 8.5% in 2023.
That means resistance to all five antibiotics used in the report’s definition: ampicillin, azithromycin, ceftriaxone, ciprofloxacin, and trimethoprim-sulfamethoxazole.
It does not mean 8.5% of Americans have this infection. It also doesn’t establish a sudden nationwide explosion in cases this October.
The researchers did not routinely have sexual-exposure data, so they could not determine how each infection was acquired.
Separate research published in The Lancet Infectious Diseases in July 2026 examined transmission in England. It found distinct, intensifying sexual transmission and evidence linking antibiotic-resistance patterns to antibiotics used for another infection, gonorrhea.
That adds to the concern, but findings from England aren’t a measurement of current U.S. cases.
Read the University of Cambridge’s study summary
Does “superbug” mean untreatable?
It means treatment can be much harder.
The CDC report says there are no FDA-approved oral antimicrobial treatments for these extensively drug-resistant infections and that an optimal treatment has not been established.
But antibiotic resistance does not mean every infected person needs antibiotics or cannot recover.
The CDC says most people with shigellosis get better without antibiotics in five to seven days. Fluids and rest may be enough for mild illness; severe illness can require antibiotics, with laboratory testing helping clinicians choose a medication likely to work.
One important caution: the CDC advises against gut-slowing medicines such as Imodium for shigellosis. These can make symptoms worse, particularly when diarrhea is bloody.
What symptoms should you watch for?
Symptoms usually begin one to two days after exposure. They can include diarrhea, sometimes bloody, fever, stomach pain, and feeling like you need to poop even when your bowels are empty.
Contact a healthcare provider for bloody diarrhea, diarrhea lasting more than three days, fever, severe cramping or tenderness, or dehydration.
People with weakened immune systems should contact their provider if they develop symptoms, because illness can be more serious or last longer.
A headline cannot tell you what’s causing your stomach trouble. Those symptoms are a reason to get checked.
The two-week detail is important
For someone with shigellosis, feeling better doesn’t mean it’s immediately time to resume sex.
The CDC advises waiting at least two weeks after diarrhea ends. Its guidance applies if you or your partner has been diagnosed.
That waiting period has a reason: people can continue shedding Shigella in their stool for up to two weeks after symptoms disappear.
Wash hands with soap and water, especially after using the bathroom and before preparing food or sexual activity. While sick, don’t prepare food for others or swim, and follow health-department guidance about returning to childcare, healthcare, or food-service work.
The headline gets your attention. Knowing how it spreads, when to get help, and how long to wait gives you something useful to do with it.
