What is shigellosis?

Shigellosis is an infectious disease caused by a group of bacteria called Shigella, germs that cause diarrhea in humans.  The bacteria are named after Shiga, a Japanese scientist who discovered them over 100 years ago.

Shigella are microscopic, and they pass from persons to person through contaminated feces.
There are several types of Shigella; Group D (Shigella flexneri) and Group B (Shigella flexneri) are most common in the United States. Rare in the U.S. is Group 1 (Shigella dysenteriae), a variant that causes deadly epidemics throughout the developing world.

Where is shigellosis prevalent?

Every year, 18,000 - 20,000 cases of shigellosis occur in the United States. The illness is especially common in places with poor hygiene, and it appears more frequently in summer than in winter.  Children, especially toddlers aged 2 to 4, are the most likely individuals to get shigellosis. Many cases are related to the spread of illness in child-care settings, and many more are the result of the spread of the illness in families with small children.

Shigellosis is even more common in the developing world, where it is present in most communities most of the time.

Are there cases of shigellosis in Montgomery County?

There were 28 cases of Shigellosis reported in Montgomery County in 2003. The number jumped to 41 in 2004 and went back down to 20 in 2005.

What are the symptoms of shigellosis?

Most people infected with Shigella develop fever, stomach cramps and diarrhea (usually bloody) starting a day or two after they are exposed to the bacterium. Shigellosis usually goes away on its own within five to seven days, but some people, especially children and the elderly have such severe diarrhea that they must be hospitalized. Some individuals experience no symptoms, but they pass Shigella bacteria to others.

Shigella pass from one infected person to the next when bacteria from stools or contaminated fingers reach another person's mouth. This may happen when proper handwashing habits are not followed or when family members or playmates have contact with toddlers who are not yet fully toilet trained.
Shigellosis can be a result of eating food contaminated by flies or by food handlers who forget to wash their hands with soap and water after using the bathroom. Vegetables can be contaminated if they're harvested in a field with sewage in it.

Some Shigella infections come from drinking or swimming in water contaminated by sewage or by someone with shigellosis swimming in it.

Those who suffer with shigallosis usually recover completely, though some may have to wait several months for their bowel habits to return to normal. About three percent of people infected with Group D Shigella (Shigella  flexneri)  will later develop Reiter's syndrome, a reaction to the bacteria that causes joint pain, eye irritation painful urination and chronic arthritis.

How is shigallosis treated?

Because several types of diseases cause diarrhea and bloody diarrhea, proper treatment depends on which germ is causing the problem. Laboratory tests on the stools of an infected person can determine whether or not the person has shigellosis and, if so, what type of bacteria is present.

Once the cause of illness is determined, a patient's doctor can prescribe the proper medication to treat the infection. The most common treatment for shigellosis includes antibiotics such as ampicillin (Bactrim), trimethoprim/sulfamethoxazole (Septra), nalidixic acid, or ciprofloxacin.

Though treatment kills usually kills the Shigella bacteria and shortens the illness, some Shigella bacteria have become resistant to antibiotics. In these cases, using antibiotics to treat shigellosis can actually make the germs more resistant in the future.

Because individuals with mild infections usually recover quickly without antibiotics, when large groups of people in a community are affected by shigellosis, antibiotics may be used only to treat the most severe cases.

Once someone has shigellosis, he or she will not likely get reinfected with the same strain, at least for several years. He or she can, however, be infected with other types of Shigella.

What can I do to keep from getting shigellosis?

There is no vaccine to prevent shigellosis, but the spread of Shigella can be stopped by maintaining proper hygiene at all times.

The following tips can help prevent shigellosis infection:

• Wash hands thoroughly with soap, especially after going to the bathroom, after changing diapers, and before preparing foods or beverages
• Properly dispose of dirty diapers
• Disinfect diaper changing areas after using them
• Keep children with diarrhea out of child care settings
• Supervise handwashing of toddlers and small children after they use the toilet
• Don't allow people with diarrhea to prepare food for others
• Avoid drinking pool water
• If you travel to the developing world "boil it, cook it, peel it, or forget it"
• If you travel to developing countries, If you are infected with shigellosis, make sure that your doctor notifies the Health Department. It is important to know if many cases have occurred at the same time, because it may mean that a restaurant, water supply or daycare center needs attention.

For more information about shigellosis check with your doctor or health department, or consult the CDC web site: www.cdc.gov/ncidod/dbmd/diseaseinfo/shigellosis_g.htm