Shigellosis

Shigellosis is an infection of the intestine caused by the Shigella bacteria. These bacteria are a common cause of diarrhea, especially in developing countries.

Shigella bacteria are found in the feces (stool) of a person with shigellosis and are spread by direct person-to-person contact through the fecal-oral route. This means that feces (usually tiny, invisible amounts) from the person with shigellosis must get into the mouth of another person for the infection to spread. This can happen if you eat food or drink water that has become contaminated, especially if it was handled by someone who was ill with shigellosis and did not properly washed his or her hands before handling the food. Shigella bacteria can also be spread sexually through contact with a person’s feces during sexual activities or through the use of sex toys.

Some people with shigellosis may not show any symptoms but still spread the infection to others. Shigellosis may also continue to be spread from one person to another for up to 4 weeks after symptoms end.

Symptoms can range from mild to severe, and usually appear 1 to 3 days (sometimes up to 7 days) after a person is in contact with the bacteria. In healthy people, symptoms may include diarrhea (sometimes bloody or with mucous), abdominal cramps, fever, nausea, vomiting and dehydration. Young children, the elderly, or people with weak immune systems may experience more severe symptoms and complications.

Most people with shigellosis are ill for 4 to 7 days and recover with no treatment. Anyone with diarrhea should drink plenty of fluids to prevent dehydration. If symptoms are persistent or severe (for example, high fever, bloody diarrhea, severe stomach cramping or tenderness, dehydration, or feeling very sick), it is important to see a healthcare provider. Talk to your healthcare provider before using anti-diarrheal medications that slow down your bowels because these medications may make your symptoms worse.

Generally, people can return to work and school when they feel better and no longer have symptoms.  People who handle food as part of their work, those who provide health care services, and those who work in or attend a child care centre must stay home and away from work or daycare if they are ill with shigellosis. Ottawa Public Health will advise when they may return to work.

To prevent becoming ill with shigellosis:

• Wash your hands well with soap and water for at least 15 seconds before preparing food, before eating, after using the toilet, after changing a diaper, after sexual activity and anytime hands might be dirty.
• Do not eat raw seafood or fruits and vegetables that have been washed in untreated water; wash raw fruits and vegetables well with clean running water before eating.
• When travelling, avoid local water where the supply is uncertain; instead use only sealed bottled water or treated (chemically disinfected or boiled) water for drinking, brushing teeth, preparing foods, making ice and cooking.
• When travelling, beware of raw foods washed in local water; eat only cooked food and raw fruit that can be peeled after it has been washed with water from a safe source.
• Avoid preparing food or drinks if you have diarrhea.
• Wait to resume sexual activity until you no longer have diarrhea. You may continue to have Shigella bacteria in your stool for a few weeks after you recover, so wash your body (genitals, anus, and hands especially) before and after sexual activity.

Ottawa Public Health (OPH) must be notified by health care providers and laboratories when a person has shigellosis. OPH conducts an investigation to try to determine the cause or source of infection, provides education to the person with shigellosis, and follows up with the person’s health care provider as necessary. OPH also investigates close contacts of a person for possible exposure. OPH will advise people ill with shigellosis and their contacts when they may return to work and child care. If a common source of illness is identified, OPH will investigate further to determine if additional public health actions are required.