Shigellosis is an infectious disease caused by a group of bacteria called Shigella (shih-GEHL-uh). Most who are infected with Shigella develop diarrhea, fever, and stomach cramps starting a day or two after they are exposed to the bacteria. Shigellosis usually resolves in 5 to 7 days. Some people who are infected may have no symptoms at all, but may still pass the Shigella bacteria to others. The spread of Shigella can be stopped by frequent and careful handwashing with soap and taking other hygiene measures.

When gastrointestinal illness is associated with the rod-shaped, gram-negative bacterium Shigella, it is called bacillary dysentery, or shigellosis. Infections can be caused by S. dysenteriae, S. flexneri, S. boydii, and/or S. sonnei that colonize the GI tract. Shigellosis can be spread from hand to mouth or through contaminated food and water. Most commonly, it is transmitted through the fecal-oral route.

Shigella bacteria invade intestinal epithelial cells. When taken into a phagosome, they can escape and then live within the cytoplasm of the cell or move to adjacent cells. As the organisms multiply, the epithelium and structures with M cells of the Peyer’s patches in the intestine may become ulcerated and cause loss of fluid. Stomach cramps, fever, and watery diarrhea that may also contain pus, mucus, and/or blood often develop. More severe cases may result in ulceration of the mucosa, dehydration, and rectal bleeding. Additionally, patients may later develop hemolytic uremic syndrome (HUS), a serious condition in which damaged blood cells build up in the kidneys and may cause kidney failure, or reactive arthritis, a condition in which arthritis develops in multiple joints following infection. Patients may also develop chronic post-infection irritable bowel syndrome (IBS).

S. dysenteriae type 1 is able to produce Shiga toxin, which targets the endothelial cells of small blood vessels in the small and large intestine by binding to a glycosphingolipid. Once inside the endothelial cells, the toxin targets the large ribosomal subunit, thus affecting protein synthesis of these cells. Hemorrhaging and lesions in the colon can result. The toxin can target the kidney’s glomerulus, the blood vessels where filtration of blood in the kidney begins, thus resulting in HUS.

Stool samples, which should be processed promptly, are analyzed using serological or molecular techniques. One common method is to perform immunoassays for S. dysenteriae. Other methods that can be used to identify Shigella include API test strips, Enterotube systems, or PCR testing. The presence of white blood cells and blood in fecal samples occurs in about 70% of patients. Severe cases may require antibiotics such as ciprofloxacin and azithromycin, but these must be carefully prescribed because resistance is increasingly common.

Shigellosis is a diarrheal disease caused by a group of bacteria called Shigella. Most people get shigellosis after having close contact with an infected person, eating or drinking contaminated food or water, or touching contaminated surfaces and putting their finger in their mouth. Common symptoms include diarrhea, fever, and stomach pain, and symptoms usually last up to 7 days. Shigella germs spread easily from person to person. The best way to prevent this spread is to practice good hygiene, including frequent handwashing.

Key Facts

• Shigella infections cause about 450,000 cases of diarrhea in the United States each year, and treatment results in an estimated $93 million in direct annual medical costs.
• Most people get shigellosis after having close contact with an infected person or by eating or drinking contaminated food or water.
• Symptoms of shigellosis include diarrhea, fever, and stomach pain, and symptoms usually last up to 7 days.
• Frequent handwashing with soap and water is one of the best ways to protect yourself and others from Shigella infection.

Just a Few Shigella Germs Can Make You Sick

Shigella is difficult to control because it spreads easily and rapidly between people, making the bacteria highly contagious. Protect yourself by practicing good hygiene and learning about the risks for infection.

Wash Your Hands. Teach Kids to Do the Same.

Handwashing is one of the best ways to avoid becoming sick with shigellosis. Carefully wash your hands with soap and water before preparing food and eating, and after using the toilet or changing diapers.

Don’t Swallow the Water

Shigella germs are spread easily in food and water. Avoid swallowing water from swimming pools, splash pads, ponds, rivers, and lakes. If you are sick (or were recently sick) with shigellosis, help protect others from getting sick by staying out of the water.

Practice Safe Sex

Shigella germs can spread during oral or anal sex, and anal play (rimming or fingering). Protect yourself and your partner by washing your hands and body with soap and water, before and after sex. Be sure to use condoms and other barriers during sex.

Follow Safe Eating and Drinking Habits When Traveling

When traveling internationally, stick to safe eating and drinking habits, and wash your hands often with soap and water.

Prevention Tips

• Wash hands with soap and water for at least 20 seconds, especially before eating or preparing food for others, and after using the toilet or changing diapers. Make handwashing a family activity by teaching kids when and how to wash their hands too.
• Avoid swallowing water from ponds, lakes, or swimming pools.
• Avoid sexual activity with those who have diarrhea or recently (several weeks) recovered from shigellosis. Use barriers during sex, such as condoms and dental dams, and wash your hands, genitals, and anus before and after sexual activity.
• When traveling internationally, stick to safe eating and drinking habits, and wash hands often with soap and water.
• Follow recommended steps to safe and healthy diapering.
  • Clean up any leaks or spills of diaper contents right away.
  • Throw away soiled diapers in a covered, lined garbage can.
  • Wash your hands (and the child’s hands) immediately after the diapers are changed.

What is shigellosis?

Shigellosis is a diarrheal disease caused by a group of bacteria called Shigella.Shigella causes about 500,000 cases of diarrhea in the United States annually. There are four different species of Shigella:

• Shigella sonnei (the most common species in the United States)
• Shigella flexneri
• Shigella boydii
• Shigella dysenteriae

S. dysenteriae and S. boydii are rare in the United States, though they continue to be important causes of disease in the developing world. Shigella dysenteriae type 1 can be deadly.

How is shigellosis spread?

Shigella germs are in the stool (poop) of sick people while they have diarrhea and for up to a week or two after the diarrhea has gone away. Shigella germs are very contagious; it takes just a small number of Shigella germs to make someone sick. People can get shigellosis when they put something in their mouths or swallow something that has come into contact with the stool of someone else who is sick with shigellosis. People could get sick by:

• Getting Shigella germs on their hands and then touching your food or mouth. You can get Shigella germs on your hands after:
  • Touching surfaces contaminated with germs from stool from a sick person, such as toys, bathroom fixtures, changing tables or diaper pails
  • Changing the diaper of a sick child or caring for a sick person
• Eating food that was prepared by someone who is sick with shigellosis
• Swallowing recreational water (for example, lake or river water) while swimming or drinking water that is contaminated with stool (poop) containing the germ
• Having exposure to stool during sexual contact with someone who is sick or recently (several weeks) recovered from shigellosis.

What are the symptoms of shigellosis and how long do they last?

Symptoms of shigellosis typically start 1–2 days after exposure to the germ and include:

• Diarrhea (sometimes bloody)
• Fever
• Stomach pain
• Feeling the need to pass stool [poop] even when the bowels are empty

For most people, symptoms usually last about 5 to 7 days. In some cases, it may take several months before bowel habits (for example, how often someone passes stool and the consistency of their stool) are entirely normal.

Who is most likely to get shigellosis?

• Young children are the most likely to get shigellosis, but people of all ages are affected. Many outbreaks are related to childcare settings and schools, and illness commonly spreads from young children to their family members and others in their communities because it is so contagious.
• Travelers to developing countries may be more likely to get shigellosis, and to become infected with strains of Shigella bacteria that are resistant to important antibiotics. Travelers may be exposed through contaminated food, water (both drinking and recreational water), or surfaces. Travelers can protect themselves by strictly following food and water precautions, and washing hands with soap frequently.
• Gay and bisexual men and other men who have sex with men (MSM)^† are more likely to acquire shigellosis than the general adult population. Shigella passes from feces or soiled fingers of one person to the mouth of another person, which can happen during sexual activity. Many shigellosis outbreaks among MSM have been reported in the United States, Canada, Japan, and Europe since 1999.
• People who have weakened immune systems due to illness (such as HIV) or medical treatment (such as chemotherapy for cancer) can get a more serious illness. A severe shigellosis may involve the infection spreading into the blood, which can be life-threatening.
• Large outbreaks of shigellosis often start in childcare settings and spread among small social groups such as intraditionally observant Jewish communities. Similar outbreaks could occur among any race, ethnicity or community social circle because Shigella germs can spread easily from one person to another.

^† The term “men who have sex with men”is used in CDC surveillance systems because it indicates men who engage in behaviors that may transmit Shigella infection, rather than how someone identifies their sexuality.

How can shigellosis be diagnosed?

Many kinds of germs can cause diarrhea. Knowing which germ is causing an illness is important to help guide appropriate treatment. Healthcare providers can order laboratory tests to identify Shigella germs in the stool of an infected person.

How can shigellosis be treated?

People who have shigellosis usually get better without antibiotic treatment in 5 to 7 days. People with mild shigellosis may need only fluids and rest. Bismuth subsalicylate (for example, Pepto-Bismol) may be helpful, but people sick with shigellosis should not use medications that cause the gut to slow down and interfere with the way the body digests food, such as loperamide (for example, Imodium) or diphenoxylate with atropine (for example, Lomotil).

Healthcare providers may prescribe antibiotics for people with severe cases of shigellosis to help them get better faster. However, some antibiotics are not effective against certain types of Shigella. Healthcare providers can order laboratory tests to determine which antibiotics are likely to work. Tell your healthcare provider if you do not get better within a couple of days after starting antibiotics. They can do more tests to learn whether your type of Shigella bacteria can be treated effectively with the antibiotic you are taking. If not, your doctor may prescribe another type of antibiotic.

How can I reduce my chance of getting shigellosis?

You can reduce your chance of getting sick from Shigella by taking these steps:

• Carefully washing your hands with soap and water during key times:
  • Before preparing food and eating.
  • After changing a diaper or helping to clean another person who has defecated (pooped).
• If you care for a child in diapers who has shigellosis, promptly throw away the soiled diapers in a covered, lined garbage can. Wash your hands and the child’s hands carefully with soap and water right after changing the diapers. Clean up any leaks or spills of diaper contents immediately.
• Avoid swallowing water from ponds, lakes, or untreated swimming pools.
• When traveling internationally, stick to safe eating and drinking habits, and wash hands often with soap and water.
• Avoid having sex (vaginal, anal, and oral) for one week after your partner recovers from diarrhea. Because Shigella germs may be in stool for several weeks, follow safe sexual practices, or ideally avoid having sex, for several weeks after your partner has recovered.

I was diagnosed with shigellosis. What can I do to avoid giving it to other people?

• Wash your hands carefully and frequently with soap and water, especially after using the bathroom.
• Do not prepare food for others while you are sick. After you get better, wash your hands carefully with soap and water before preparing food for others.
• Stay home from childcare, school and food service facilities while sick. Your local health department may have a policy on when to return to childcare or school. Refer to your local health department website for more information.
• Avoid swimming until you have fully recovered.
• Wait to have sex (vaginal, anal, and oral) for one week after you no longer have diarrhea. Because Shigella germs may be in stool for several weeks, follow safe sexual practices, or ideally avoid having sex, for several weeks after you have recovered.

My child was diagnosed with shigellosis. How can I keep others from catching it?

• Supervise handwashing of toddlers and small children after they use the bathroom. Wash your hands and your infant’s hands with soap and water after diaper changes.
• Throw away soiled diapers in a covered, lined garbage can. Clean diaper changing areas after using them.
• Keep your child out of childcare and group play settings while sick with diarrhea, and follow the guidance of your local health department about returning your child to their childcare facility.
• Avoid taking your child swimming or to group water play venues until after they no longer have diarrhea.
  • Have children and staff shower with soap before swimming.
    • If a child is too young to shower independently, have staff wash the child, particularly the rear end, with soap and water.
  • Take frequent bathroom breaks or check their diapers often.
  • Change diapers in a diaper-changing area or bathroom and not by the water.
  • Discourage children from getting the water in their mouths and swallowing it.

People who are sick from Shigella infection usually start experiencing symptoms 1 to 2 days after contact with the germ. Symptoms of shigellosis include:

• Diarrhea (sometimes bloody)
• Fever
• Stomach pain
• Feeling the need to pass stool [poop] even when the bowels are empty

Some people with shigellosis will not have any symptoms.

Symptoms usually last 5 to 7 days, but some people may experience symptoms anywhere from a few days to 4 or more weeks. In some cases, it may take several months before bowel habits (for example, how often someone passes stool and the consistency of their stool) are entirely normal.

When to Contact Your Doctor

People with diarrhea should contact their healthcare provider if they have any of these symptoms:

• Fever
• Bloody diarrhea
• Severe stomach cramping or tenderness
• Dehydrated
• Feel very sick.

People who are in poor health or who have immune systems weakened from diseases such as HIV/AIDS, or chemoterhapy for cancer, are more likely to get sick for a longer period of time if they have shigellosis. They should contact their healthcare provider if they think they have shigellosis to determine the best course of treatment.

Rare Symptoms from Shigella Infections

Post-infectious arthritis

About 2% of people who are infected with the type of Shigella called Shigella flexneri will experience post-infectious arthritis, which causes joint pains, eye irritation, and painful urination. The syndrome only occurs in people who have specific genetic makeup that puts them at risk. It can last for months or years, and can lead to chronic arthritis. Post-infectious arthritis usually does not occur in people who get sick from the other types of Shigella, called S. sonnei, S. boydii, or S. dystenteriae.

Bloodstream infections

People with shigellosis can get bloodstream infections caused by Shigella germs or by other germs in the gut that get into the bloodstream when shigellosis damages intestinal linings. Bloodstream infections are most common among patients with weakened immune systems, such as those with HIV, cancer, or severe malnutrition.

Seizures

A few young children with shigellosis have had generalized seizures, but the seizures usually go away without treatment. Children with shigellosis who experience seizures typically have a high fever or abnormal blood electrolytes (salts). However, healthcare professionals do not know why the seizures occur.

Hemolytic-uremic syndrome

Hemolytic-uremic syndrome (HUS) occurs when bacteria enter the digestive system and produce a toxin that destroys red blood cells. Patients with HUS often have bloody diarrhea. The syndrome can be deadly. In patients with shigellosis, HUS is associated with Shiga toxin-producing Shigella, most often Shigella dystenteriae.

People who are sick with shigellosis have Shigella germs in their stool (poop) while they have diarrhea and for up to a week or two after the diarrhea has gone away. Shigella is very contagious; just a small amount of germs can make someone sick. People could get sick by:

• Getting Shigella germs on their hands and then touching their food or mouth. This may happen after:
  • Touching surfaces contaminated with germs from stool from a sick person, such as toys, bathroom fixtures, changing tables or diaper pails.
  • Changing the diaper of a sick child or caring for a sick person.
• Eating food that was prepared by someone who is sick with shigellosis.
  • Foods that are consumed raw are more likely to be contaminated with Shigella germs.
  • Shigella germs can contaminate fruits and vegetables if the fields where they grow contain human waste.
• Swallowing recreational water (for example, lake or river water) while swimming or drinking water that is contaminated with stool (poop) containing the germ.
• Having exposure to stool during sexual contact with someone who is sick or recently (several weeks) recovered from shigellosis.

Groups of People Who Are Most Likely to Get Shigellosis

• Young children are the most likely to get shigellosis, but people of all ages can get this disease. Many outbreaks are related to childcare settings and schools. Illness commonly spreads from young children to their family members and others in their communities because it is so contagious.
• Travelers to developing countries may be more likely to get shigellosis, and to become infected with strains of Shigella bacteria that can’t be treated effectively by important antibiotics. Travelers may get sick from food, drinking water, recreational water, and surfaces containing Shigella germs. Travelers can protect themselves by sticking to safe eating and drinking habits, and washing hands often with soap and water.
• Gay or bisexual men and other men who have sex with men^† are more likely to get shigellosis than other adults. Shigella germs pass from stools (poop) or soiled fingers of one person to the mouth of another person, which can happen during sexual activity. Many shigellosis outbreaks among gay and bisexual men have been reported in the United States, Canada, Tokyo, and Europe since 1999.
• People whose immune systems are weakened due to illness (such as HIV) or medical treatment (such as chemotherapy for cancer) can get a more serious illness. A severe shigellosis illness may involve the infection spreading into the blood, which can be life-threatening.
• Large outbreaks of shigellosis often start in childcare settings and spread among small social groups such as in traditionally observant Jewish communities. Similar outbreaks could occur among any race, ethnicity or community social circle because Shigella germs can spread easily from one person to another.

^† The term “men who have sex with men” is used in CDC surveillance systems because it indicates men who engage in behaviors that may transmit Shigella infection, rather than how someone identifies their sexuality.

Many kinds of germs can cause diarrhea. Knowing which germ is causing an illness is important to help guide appropriate treatment. Healthcare providers can order laboratory tests to identify Shigella germs in the stool (poop) of someone who is sick.

Most people will recover from shigellosis without treatment in 5 to 7 days. People who have shigellosis should drink plenty of fluids to prevent dehydration. Contact your healthcare provider if you, or one of your family members, have a fever, bloody diarrhea, severe stomach cramping or tenderness, are dehydrated, or feel very sick. People who are in poor health or who have weakened immune systems, such as from HIV/AIDS or chemotherapy treatment for cancer, also should contact their healthcare provider because they are more likely to get sick for a longer period of time.

• In some people, bismuth subsalicylate (for example, Pepto-Bismol) can help to relieve symptoms.
• People with shigellosis should not use anti-diarrheal medication, such as loperamide (for example, Imodium) or diphenoxylate with atropine (for example, Lomotil). These medications may make symptoms worse.
• Healthcare providers may prescribe antibiotics for some people who have severe cases of shigellosis. Antibiotics such as ciprofloxacin (common treatment for adults), and azithromycin (common treatment for children) are useful for severe cases of shigellosis because they can help people get better faster. However, some antibiotics are not effective against certain types of Shigella bacteria. Healthcare providers can order laboratory tests to determine which antibiotics are likely to work.

People who have shigellosis should follow their healthcare provider’s advice. If your healthcare provider prescribes antibiotics, let them know if you do not get better within a couple of days after starting the medication. They can do more tests to learn whether your type of Shigella bacteria can be treated effectively with the antibiotic you are taking. If not, your doctor may prescribe another type of antibiotic.

Drugs that kill or stop the growth of bacteria germs are called antibiotics. Antibiotic resistance is when a bacteria, such as Shigella, resists the effects of an antibiotic – that is, the germs are not killed and their growth is not stopped.

Compared with most treatable Shigella infections, antibiotic-resistant shigellosis:

• can be harder to treat,
• may increase the cost of treatment,
• and may lengthen the time someone is sick, which increases the chance that the bacteria will spread.

How do I know if my infection is drug resistant?

The only way to know if you have antibiotic-resistant Shigella is if your healthcare provider orders laboratory testing of a sample of your stool (poop). Laboratory tests can check which antibiotics may help treat your infection. If you are being treated with antibiotics for shigellosis but do not feel better within a couple of days, tell your healthcare provider. You may need additional tests to check whether the type of Shigella bacteria you have is resistant to the antibiotics.

What should I do if I have an antibiotic-resistant Shigella infection

Please follow the advice of your healthcare provider. Not all Shigella infections require antibiotics for treatment, but if you are started on antibiotics and do not feel better within a couple of days, tell your healthcare provider. Help keep others from getting sick by following the recommendations below:

• Wash your hands carefully with soap and water after using the toilet.
• Stay home while you are sick.
  • If you work in healthcare, childcare, or the food service industry, follow your local health department’s guidance about when it is safe to return to work.
• Do not prepare food for others, if possible, while you are sick.
• Wait to have sex (vaginal, anal, and oral) for one week after you no longer have diarrhea. Because Shigella germs may be in stool for several weeks, follow safe sex practices, or ideally avoid having sex, for several weeks after you have recovered.

Prevent antibiotic resistant Shigella

The use of antibiotics is the single most important factor leading to antibiotic resistance around the world. Simply using antibiotics creates resistance. These drugs should only be used to manage infections. Avoiding infections in the first place reduces the need for antibiotics and reduces the likelihood that resistance will develop.

Shigella germs spread easily from one person to another; just a small amount of Shigella germs can make someone sick. Understanding how to prevent the spread of Shigella germs can help you protect yourself and your loved ones from getting sick.

How can I avoid getting sick from Shigella bacteria?

People usually get sick from Shigella bacteria after putting something in their mouth or swallowing something that has come into contact with the stool (poop) of someone else who is sick from Shigellabacteria. There is no vaccine to prevent shigellosis. However, you can reduce your chance of getting shigellosis by:

• Carefully washing your hands with soap and water during key times:
  • Before eating or preparing food for others
  • After changing a diaper or helping to clean another person who went to the bathroom
• If you care for a child in diapers who has shigellosis, promptly throw away soiled diapers in a covered, lined garbage can. Wash your hands and the child’s hands carefully with soap and water immediately after changing the diapers. Clean up any leaks or spills of diaper contents immediately.
• Avoid swallowing water from ponds, lakes, or untreated swimming pools.
• When traveling internationally, follow safe food and water guidelines and wash hands often with soap and water.
• Avoid sexual activity with those who have diarrhea or who recently (several weeks) recovered from shigellosis.

If you are sick with shigellosis you can prevent others from getting sick by:

• Washing hands often, especially
  • Before preparing food or eating
  • After using the bathroom or changing diapers
• NOT preparing food if you are sick
• NOT sharing food with anyone if you or your family members are sick
• NOT swimming
• NOT having sex (vaginal, anal, and oral) for one week after you no longer have diarrhea. Because Shigella germs may be in stool for several weeks, follow safe sexual practices, or ideally avoid having sex, for several weeks after you have recovered.
• Staying home from school or from healthcare, food service, or childcare jobs while sick or until your health department says it’s safe to return

Shigella germs are found in the stool (poop) of sick people when they have diarrhea and for up to two weeks after the diarrhea has gone away. Shigella infection is spread when people put something (for example, a finger, food, or objects) in their mouths or swallow something that has come into contact with stool of someone sick with shigellosis. This includes exposure to stool through sexual contact. Men who have sex with men (MSM) are more likely than others to get infected with Shigella that is resistant to antibiotics commonly used to treat adults who have shigellosis.

Practice Safer Sex

The following recommendations can help prevent the spread of Shigella germs during sex.

Sick people may have Shigella germs on their skin in the anal and genital areas, including the thighs and buttocks. You cannot tell if someone hasShigella germs in these areas just by looking at them. To protect yourself and your partners from Shigella, follow these steps:

• Wait to have sex (vaginal, anal, and oral) for one week after you no longer have diarrhea. Because Shigella germs may be in stool for several weeks, follow safe sex practices, or ideally avoid having sex, for several weeks after you or your partner have recovered.

• Reduce your contact with poop during sex by:
  • Washing your hands, genitals, and anus with soap and water before and after sexual activity.
  • Using barrier methods during sex. Barrier methods include condoms, dental dams, and cut-open condoms. Sex includes oral (mouth-to-penis, mouth-to-vagina, mouth-to-anus), anal (penis-to-anus), and vaginal (penis-to-vagina) sex. Using latex gloves during anal fingering or fisting.
  • Using condoms the right way, every time you have anal and vaginal sex, which will also help prevent other sexually transmitted infections.
  • Washing your hands with soap and water immediately after touching a used condom or other barrier method.
  • Washing sex toys with soap and water after each use, and washing hands after touching used sex toys.

^† The term “men who have sex with men” is used in CDC surveillance systems because it indicates men who engage in behaviors that may transmit Shigella infection, rather than how someone identifies their sexuality.