Shigellosis

(from the Canadian Institute of Public Health Inspectors)

What is Shigellosis?

Shigellosis is an acute bacterial disease that causes diarrhea, often bloody diarrhea, accompanied by fever, nausea, and sometimes vomiting and cramps. The disease is commonly referred to as dysentery. Some cases can be quite severe and symptoms can last for several days or several weeks, with an average of 4 - 7 days. The disease is more severe in children than it is in adults and is associated with Hemolytic Uremic Syndrome (HUS), a leading cause of kidney failure in the elderly and young children. Symptoms of HUS include irritability, fatigue, paleness of the skin, puffiness around the eyes and ankles. and a decrease in the amount of urine produced.

How is Shigellosis Spread?

People are the only significant source for Shigella bacteria. The bacteria is found in the intestines of infected people. Infection can occur after the ingestion of very few organisms (10-100). People who go to the bathroom and do not wash their hand properly can pass the disease to others directly by physical contact (touching) or indirectly through food preparation. Because it takes so few organisms to cause illness person-to-person spread between family members is common. Shigellosis can also be spread by drinking water contaminated with sewage. Flies may also transfer the organism on their feet after being in contact with infected feces and then landing on uncovered food left unrefrigerated. Avoid eating raw shellfish such as clams, crabs, oysters or mussels that have been exposed to sewage. Many seaport cities world wide let the tides carry their sewage out into the ocean where shellfish become contaminated.

How is Shigellosis Prevented?

• Thorough hand washing is the best prevention. Make sure hands are properly washed after using the toilet and handling diapers.
• Because of the small numbers of bacteria required to cause illness, infected people should not work as food handlers or provide child care until they are Shigella free.
• Do not eat raw shellfish.
• Drink water from a safe supply. Boil water for at least 5 minutes or drink bottled water when travelling if you are unsure of the supply. Remember that ice cubes could also be contaminated.
• Avoid swimming in water that may be contaminated.

For more information, contact your public health department.