Health Department - Shigellosis

Frequently Asked Questions (FAQ's):

• What is Shigellosis?
• What are the symptoms?
• How is it spread?
• How can I prevent Shigellosis?
• Is there treatment?
• Where can I find more information?

What is Shigellosis?

Shigellosis is an infectious disease caused by a group of bacteria called Shigella. The Shigella germ is actually a family of bacteria that can cause diarrhea in humans. They are microscopic living creatures that pass from person to person.

What are the symptoms?

Most who are infected with Shigella develop diarrhea, fever, and stomach cramps starting a day or two after they are exposed to the bacteria. The diarrhea is often bloody. Shigellosis usually resolves in 5 to 7 days.

How is it spread?

The Shigella bacteria pass from one infected person to the next. Shigella are present in the diarrheal stools of infected persons while they are sick and for up to a week or two afterwards. Most Shigella infections are the result of the bacterium passing from stools or soiled fingers of one person to the mouth of another person. This happens when basic hygiene and handwashing habits are inadequate and can happen during certain types of sexual activity. It is particularly likely to occur among toddlers who are not fully toilet-trained. Family members and playmates of such children are at high risk of becoming infected.

Shigella infections may be acquired from eating contaminated food. Contaminated food usually looks and smells normal. Food may become contaminated by infected food handlers who forget to wash their hands with soap after using the bathroom. Vegetables can become contaminated if they are harvested from a field with sewage in it. Flies can breed in infected feces and then contaminate food. Water may become contaminated with Shigella bacteria if sewage runs into it, or if someone with shigellosis swims in or plays with it (especially in splash tables, untreated wading pools, or shallow play fountains used by daycare centers). Shigella infections can then be acquired by drinking, swimming in, or playing with the contaminated water.  Outbreaks of shigellosis have also occurred among men who have sex with men.

Prevention:

Currently, there is no vaccine to prevent shigellosis. However, the spread of Shigella from an infected person to other persons can be stopped by frequent and careful handwashing with soap. Frequent and careful handwashing is important among all age groups. Handwashing among children should be frequent and supervised by an adult in daycare centers and homes with children who have not been fully toilet trained.

If a child in diapers has shigellosis, everyone who changes the child's diapers should be sure the diapers are disposed of properly in a closed-lid garbage can, and should wash his or her hands and the child’s hands carefully with soap and warm water immediately after changing the diapers. After use, the diaper changing area should be wiped down with a disinfectant such as diluted household bleach, Lysol* or bactericidal wipes.  When possible, young children with a Shigella infection who are still in diapers should not be in contact with uninfected children.

Basic food safety precautions and disinfection of drinking water prevents shigellosis from food and water. However, people with shigellosis should not prepare food or drinks for others until they have been shown to no longer be carrying the Shigella bacterium, or if they have had no diarrhea for at least 2 days.  At swimming beaches, having enough bathrooms and handwashing stations with soap near the swimming area helps keep the water from becoming contaminated.  Daycare centers should not provide water play areas.

Simple precautions taken while traveling to the developing world can prevent shigellosis. Drink only treated or boiled water, and eat only cooked hot foods or fruits you peel yourself. The same precautions prevent other types of traveler's diarrhea.

Treatment:

Persons with mild infections usually recover quickly without antibiotic treatment.   However, appropriate antibiotic treatment kills Shigella bacteria, and may shorten the illness by a few days. The antibiotics commonly used for treatment are ampicillin, trimethoprim/sulfamethoxazole (also known as Bactrim* or Septra*), ceftriaxone (Rocephin*), or, among adults, ciprofloxacin. Some Shigella bacteria have become resistant to antibiotics.  This means some antibiotics might not be effective for treatment.  Using antibiotics to treat shigellosis can sometimes make the germs more resistant. Therefore, when many persons in a community are affected by shigellosis, antibiotics are sometimes used to treat only the most severe cases. Antidiarrheal agents such as loperamide (Imodium*) or diphenoxylate with atropine (Lomotil*) can make the illness worse and should be avoided.

For more information regarding Shigella please visit the Centers for Disease Control Shigella web page at http://www.cdc.gov/nczved/dfbmd/disease_listing/shigellosis_gi.html