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Shigellosis Among Gay, Bisexual, and Other Men Who Have Sex With Men

Note: Content on this page contains mature language. 

What You Need to Know

What is sh​igellosis?

Illustration of Shigella under a microscope.

Shigellosis is a diarrheal disease caused by infection with Shigella bacteria. These bacteria are found in the poop of someone who has shigellosis. Shigella bacteria are very contagious, meaning they can easily spread from person to person. During sexual activity, Shigella bacteria from human poop can easily pass from one person to the mouth of another and make a person sick.​
Anyone can get shigellosis, but gay, bisexual, and other men who have sex with men (MSM) are among groups more likely to get shigellosis than other adults. MSM are also more likely to be infected with a type of Shigella that is more difficult to treat. ​
​Image source: CDC

Shigellosis in the U.S. and California

There are nearly 450,000 cases of shigellosis in the U.S. every year. In California, around 3,000 cases are reported each year. But there are many more unreported Shigella infections each year in California in people who did not seek medical care or get tested. Many outbreaks of shigellosis, including infections caused by Shigella that are resistant to antibiotic treatment, have been reported among MSM.

​​​How It Spreads Through Sex

A person who has shigellosis will have Shigella bacteria in their poop while they are sick and for about 2 weeks afterward. You can get shigellosis if Shigella bacteria from someone’s poop get into your mouth. This can happen while having sex or if something gets into your mouth (such as hands, fingers, and other objects) that has come in contact with poop germs.

Ways Shigella bacteria can spread through sexual activity:

  • ​​​Anal sex, oral sex, or anal play (rimming, fingering)​

  • ​​Touching or handling sex toys, used condoms/other barriers used during sex, and douching materials

It only takes a few Shigella bacteria from a tiny amount of poop to make someone sick. You can’t tell by looking if something is contaminated with germs – your hands or a sex toy may look clean, but they could still be covered with germs.​​

Shigella bacteria can spread in other ways besides sexual activity, such as through contaminated food, water, or by accidentally swallowing something that is contaminated with Shigella bacteria. Learn more about shigellosis.

Signs and Symptoms

Man sitting on couch holding his stomach with look of discomfort on his faceNot everyone infected with Shigella bacteria will have symptoms. If symptoms of shigellosis develop, they can include:

  • Diarrhea, sometimes bloody or lasting more than 3 days
  • Fever
  • Stomach pain and cramps
  • A strong, even painful urge to poop

Symptoms usually start within 1–2 days after exposure to Shigella bacteria from poop and can last about a week. Most people with mild shigellosis usually get better on their own without antibiotic treatment. People who have health conditions that weaken the immune system (such as infection with HIV) or are taking medications that weaken the immune system are more likely to get severely ill and stay sick for a longer time if they have shigellosis. People in these groups should seek medical care if they think they have shigellosis.​​


If you or a sexual partner have diarrhea (especially bloody diarrhea) lasting more than 3 days and fever, severe stomach pain, or are dehydrated as a result of diarrhea, talk to a health care provider about shigellosis. A health care provider can test your poop to see if you have shigellosis. If you have severe shigellosis, a health care provider may also test your poop to determine the kind of Shigella bacteria you’re infected with. This information is needed to better understand which antibiotics will work to treat severe shigellosis if you have it. ​​


The best way to prevent shigellosis through sex is by not having sex with someone who had diarrhea within the last 2 weeks. 

There is no vaccine to prevent shigellosis.

Important: If you or your sexual partner(s) have diarrhea OR have had diarrhea recently, WAIT at least 2 weeks until after the diarrhea ends to have sex of any kind (including playing with and/or sharing sex toys that haven’t been properly washed or cleaned). Shigella bacteria can still be in poop for a few weeks after diarrhea goes away, meaning you can still spread Shigella to other people, even if you don’t feel sick.

You can help protect yourself and your sexual partner(s) from shigellosis:

Before sex

  • Ask your partner(s) if they have or recently had diarrhea. If so, WAIT to have sex until it’s been at least 2 weeks since they had diarrhea. 

  • Wash your hands, genitals, and anal area with soap and water.

    • For example, take a shower and wash your body with soap.

    • Douching and enemas may wash out some Shigella but don’t wash away 100% of Shigella bacteria, and instead might even worsen the spread of germs from inside your anus to the skin and areas outside it. Make sure to wash your hands, body, and douching materials with soap and water after douching.

During sex (and while using sex toys)

  • Use barriers like condoms and dental dams during oral sex (including rimming or anilingus, mouth-to-anus) to help keep poop germs out of your mouth.

  • Use disposable gloves (latex or nitrile) during anal fingering or fisting to keep your hands and fingers clean.

​After sex

    • Throw away used sexual barriers (condoms, dental dams, and gloves) in the trash.

    • Thoroughly wash sex toys with soap and water.

    • Wash your hands, genitals, and anal area with soap and water.

      • For example, take a shower and wash your body with soap.​​


Most people who have shigellosis get better after a week without any antibiotics or other kinds of treatment. But it’s important to know that Shigella bacteria can still be in your poop for a few weeks, even after symptoms go away. Some people need treatment with antibiotics, including people who have or are at risk for severe or long-lasting shigellosis. People who have preexisting health conditions or weakened immune systems due to certain medical conditions (such as HIV infection or cancer) or treatments (such as chemotherapy) are more likely to get severely ill and stay sick for a longer time. Severe outcomes of shigellosis in these groups can include a life-threatening blood infection. Other outcomes can also include arthritis, which can last many months to years.

Shigellosis can be treated with the right antibiotic, but it is possible to get infected with Shigella again.​  ​​

MSM are at higher risk for infection with Shigella bacteria that are resistant to antibiotics.

Antibiotics are a type of medicine that fight bacterial infections, including Shigella. Some Shigella bacteria have become antimicrobial-resistant, meaning they have developed the ability to survive the antibiotics designed to kill them, making them harder to treat. This can mean you might need to see a health care provider many times before getting the right kind of antibiotic that will work. If you have shigellosis and need treatment, some tests can help make sure you get the right kind of antibiotic to treat your infection. Antibiotics used to treat resistant forms of shigellosis may include injectable antibiotics (a shot) or antibiotics that you swallow (as pills).

Person sitting on toilet with clothes around ankles.

If you have shigellosis:

Take care of yourself.

  • Drink plenty of fluids so you don’t get dehydrated (diarrhea can make you lose fluids/water quickly).

  • Take medication exactly as prescribed by your health care provider. (This can help prevent antimicrobial resistance and the spread of resistant germs.)

  • Do not take over-the-counter anti-diarrheal medicine, such as Imodium (generic name: loperamide), because it can make your symptoms worse.

Take care of your partner(s) and those around you.

  • Do not have sex while you have diarrhea and for at least 2 weeks after your diarrhea goes away.

    • Consider telling your sexual partner(s) if you found out you have shigellosis and just recently had sex.

  • Do not prepare food for other people, since poop germs can accidentally spread from unwashed hands to food that people may eat.

  • Wash your hands with soap and water often, especially after using the bathroom.

  • Stay out of recreational water including shared swimming pools, spas, hot tubs, ponds, and lakes while you have diarrhea and for at least 2 weeks afterward. Diarrhea and swimming don’t mix – poop germs can easily spread in water and make others sick.

  • Stay home from jobs in healthcare, food service, or childcare until your health department says it’s safe to return.​

Other Sexually Transmitted Infections

More than one kind of infection can spread through sex, so if you have shigellosis and think you got it from having sex, consider getting tested for other sexually transmitted infections (STIs), too.

Make STI Testing a Routine Part of Your Health Care

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