Shigellosis also known as bacillary dysentery or Marlow syndrome is a type of food poisoning caused by intestinal infection with Shigella bacterium. The Shigella germ is a family of bacteria that can cause diarrhoea in humans. People with shigellosis shed the bacteria in their faeces.
What Causes Shigellosis?
Shigellosis is spread when the bacteria in faeces (stool) or on soiled fingers are ingested. Poor hand-washing habits and eating contaminated food may cause the condition. Shigellosis is often found in day care centres, nursing homes, refugee camps, and other places where conditions are crowded and sanitation is poor.
Shigellosis is likely to occur among toddlers who are not fully toilet trained. Family members and playmates of infected children are also at high risk of becoming infected.
Food may become contaminated by infected food handlers who do not wash their hands with soap after using the restroom.
Vegetables can be contaminated if they are harvested from a field that has sewage in it. Also, flies can breed in infected faeces and then contaminate food.
Shigellosis can result from drinking or swimming in contaminated water. Water may become contaminated if sewage runs into it or if someone with shigellosis swims in it.
Shigellosis also can be spread through sex, especially through anal and oral sex.
Shigella is one of the leading bacterial causes of diarrhoea worldwide and is a top pathogen causing moderate-to-severe diarrhoea in African and South Asian children. It is also a major cause of illness in military personnel and travellers.
The Shigella bacteria produce toxins that can attack the lining of the large intestine, causing swelling, ulcers on the intestinal wall.
It takes as few as 10 of these bacteria to cause an infection. That means that Shigella bacteria can spread easily within families, schools, child-care centres, nursing homes, and other institutions.
Symptoms of Shigellosis
Symptoms include the following:
Diarrhoea that may be bloody or contains mucus
Nausea and vomiting
The most common neurological symptom includes seizures.
Some people who are infected may have no symptoms at all but may still spread shigellosis to others.
1 -7 days (usually 1-3 days)
Duration of Illness
How is Shigellosis Diagnosed?
Because many different diseases can cause a fever and bloody diarrhoea, lab tests are the best way to diagnose shigellosis. Your doctor will most likely still do a physical exam and ask you questions about your symptoms, foods you have recently eaten, and your work and home environments. A stool culture confirms the diagnosis. Blood tests may be done if your symptoms are severe or to rule out other causes.
How is it Treated?
Shigellosis is usually treated with antibiotics. But some types of Shigella bacteria are not killed by antibiotics. This is called resistance. Because using antibiotics can make these bacteria even more resistant, mild cases of shigellosis are often not treated with antibiotics. In this case, shigellosis is treated by managing complications until it passes. Dehydration caused by diarrhoea is the most common complication. Do not use medicines to prevent diarrhoea.
To prevent dehydration, take frequent sips of a rehydration drink (such as Pedialyte). Try to drink a cup of water or rehydration drink for each large, loose stool you have. Soda and fruit juices have too much sugar and not enough of the important electrolytes that are lost during diarrhoea, and they should not be used to rehydrate.
Try to stay with your normal diet as much as possible. Eating your usual diet will help you to get enough nutrition. Doctors believe that eating a normal diet will also help you feel better faster. But try to avoid foods that are high in fat and sugar. Also avoid spicy foods, alcohol, and coffee for 2 days after all symptoms have disappeared.
Does Shigellosis have any Complications?
After shigellosis, it may take months before your bowel movements are completely normal again. But people with diarrhoea usually recover completely.
A small number of people who are infected with one type of Shigella bacteria, Shigella flexneri, will later develop pain in their joints, irritation of the eyes, and painful urination. This is called reactive arthritis. It can last for months or years and can lead to chronic arthritis.
Who’s at Risk?
Shigellosis can affect people of any age, including teens. It's especially common in children ages 2 to 4 years old because they're often not toilet trained yet or they don't wash their hands after using the restroom.
What Do I Do?
Drink plenty of fluids and get rest. Stay home from school or work to avoid spreading the bacteria to others. If you cannot drink enough fluids to prevent dehydration, call your doctor.
How Do I Prevent It?
According to the World Health Organization, “Despite the continuing challenge posed by Shigella, there is room for optimism as advances in biotechnology have enabled the development of a new generation of candidate vaccines that shows great promise for the prevention of Shigella disease.” But such a vaccine has yet to be perfected. Thus, in the meantime, preventing infection is the best approach, and that means implementing proper sanitation measures.
Below are ways to reduce your risk of getting shigellosis:
- Wash hands with soap carefully and frequently, especially before eating, after going to the restroom, after changing diapers, and before preparing foods or beverages.
- Dispose of soiled diapers properly
- Disinfect diaper changing areas after using them.
- Keep children with diarrhoea out of child care settings while they are ill.
- Supervise hand-washing of toddlers and small children after they use the toilet.
- Do not prepare food for others while ill with diarrhoea.
- Avoid swallowing water from ponds, lakes, or untreated pools.
- When travelling in developing countries, drink only treated or boiled water, and eat only cooked hot foods or fruits you peel yourself.
- Avoid sexual activity with those who have diarrhoea or who recently recovered from diarrhoea.
- Since shigellosis is spread very quickly among children, keeping infected children out of daycare for 24 hours after their symptoms have disappeared will decrease the occurrence of shigellosis in daycares.