Types of Shigella

Shigellosis is a gastrointestinal bacterial infection, caused by a group of bacteria called Shigella. About 14,000 cases of shigellosis are reported every year in the United States, according to the Centers for Disease Control and Prevention.

There are several different types of shigella that causes shigellosis outbreaks in the United States. The most common types of shigella are shigella sonnei, shigella flexneri and shigella dysenteriae type 1.

Facts

• Shigellosis can occur one to two days after exposure to shigella bacteria, and lasts as long as five to seven days. Although shigella sonnei, also known as Group D, is the cause of two-thirds of all shigellosis cases in the United States, most of the remaining cases are caused by shigella flexneri (Group B). Shigella dysenteriae type 1 is rare in the United States, but known for causing deadly, widespread outbreaks in developing countries.

Causes

• In Shigellosis, a shigella bacterium is contagious. Getting just a little shigella bacterium in your mouth can cause the bacteria to spread from an infected person directly to another person. Food or water can also become contaminated when shared by an infected person.

  Shigellosis outbreaks can be caused by crowded living conditions and poor sanitation. Shigellosis is common among workers or residents of refugee camps and travelers in developing countries. This infection is also most commonly found in places like institutional settings and day care centers.

Symptoms

• Although many people with shigellosis have few or no symptoms, it is still possible to pass the shigella bacteria to others. Symptoms can develop within one to seven days after coming in contact with the bacteria.

  Symptoms can include watery diarrhea (occasionally including mucus or blood), abdominal cramps, nausea, vomiting and fever. In young children and the elderly, severe cases of diarrhea can lead to hospitalization. In rare cases severe infection with high fever may cause seizures in children younger than 2 years old.

Treatment

• The main goal of treating shigellosis is to avoid dehydration and replenish fluid and electrolytes lost in diarrhea. A self-care treatment can be drinking electrolyte solutions to prevent dehydration.

  In milder cases people typically recover without antibiotic treatment. However in more severe cases, antibiotics can kill the shigella bacteria and help prevent the illness from spreading. Sometimes antibiotics may not be effective because some shigella bacteria can become resistant to antibiotics. Anti-diarrheal medications should be avoided as it can worsen the condition of the illness.

Prevention

• There is currently no vaccine to prevent shigellosis, but certain precautions and preventive measures can be taken to avoid spreading and contracting the illness. Because the bacteria can be spread from an infected person to others, hand washing with soap should be practiced frequently. Try to avoid contact with anyone who may be infected. Also people who are infected should avoid contact with anyone who is not infected.

  When traveling to developing countries, drink only boiled or treated water, eat only fruits you peeled yourself and eat only cooked hot foods. If previously diagnosed, make sure all signs of shigella bacteria are no longer present before resuming any routine work or play.