Brief overview
- Description: Contagious diarrheal disease caused by infection with bacteria (shigella).
- Causes: Infection with bacteria transmitted by ill persons directly through contaminated hands or indirectly through contaminated food, drinking and bathing water, or objects
- Symptoms: Diarrhea (watery to bloody), abdominal cramps, fever and vomiting are common.
- Diagnosis: Discussion with the physician, physical examination (e.g., detection of bacteria from a stool sample).
- Treatment: The doctor usually treats shigellosis with antibiotics. In addition, the supply of fluids and electrolytes (e.g. drinking solutions) is important. Only rarely is a stay in hospital necessary.
- Prevention: Wash hands regularly, drink only clean drinking water (e.g., original sealed bottles), cook or thoroughly fry food before consumption.
What is dysentery disease?
Dysentery disease – also called shigellosis, shigella dysentery, bacterial dysentery, bacterial dysentery or shigella dysentery – is an intestinal disease caused by infection with various bacteria of the genus Shigella. They belong to the intestinal germs medically known as enterobacteria.
The infection often causes severe diarrhea and abdominal pain. In Germany, it mainly affects travelers and especially those returning from warm countries with poor hygienic conditions.
Bacterial dysentery must be distinguished from amoebic dysentery. The latter is not caused by bacteria but by the parasite Entamoeba histolytica (amoebae).
Where is shigella found?
Shigella is highly prevalent worldwide. Poor sanitary conditions and warm climates favor the spread of the disease, which is why it is particularly common in so-called developing countries. According to studies, the cases of shigellosis occurring in Germany come mainly from countries such as Egypt, Morocco, India, China and Turkey.
Typically, bacterial dysentery occurs more frequently in the warm months (summer to early fall). Mostly children under five years and young adults (between 20 and 39 years) are affected by an infection with Shigella.
In this country, dysentery sometimes also occurs in community settings (e.g., nursing homes or kindergartens) when hygiene measures are not adequately observed.
How does shigellosis develop?
Dysentery disease is caused by infection with Shigella bacteria. These bacteria begin to produce toxins (endotoxins and exotoxins) in the intestines that cause inflammation of the intestinal mucosa (usually the colon). The most common bacterial species from the shigella group include:
- Shigella sonnei: widespread mainly in Western Europe; relatively harmless
- Shigella flexneri: widespread mainly in eastern countries and the USA; rarer and rather harmless
- Shigella boydii: mainly distributed in India and North Africa
- Shigella dysenteriae: distributed mainly in the tropics and subtropics; forms both an endotoxin, which in severe cases leads to colon ulcers, and an exotoxin (Shiga toxin), which leads to severe, even bloody diarrhea and circulatory problems
How does the transmission occur?
Indirect transmission of the bacteria occurs via contaminated food, contaminated drinking water and infected objects (e.g. towels) as well as through the shared use of toilets. Transmission through bathing water contaminated with bacteria is also possible.
Infection also occurs through infected persons who do not show symptoms (asymptomatic carriers or “excretors”). Flies are able to carry stool particles contaminated with bacteria onto objects or food. It is also possible for shigella to be transmitted during sexual anal contact and occasionally through contaminated medical equipment.
Shigella is highly contagious and causes symptoms even in small amounts (less than 100 germs).
What are the symptoms of dysentery disease?
If the body excretes excessive amounts of fluid as a result of the diarrhea, it often also loses electrolytes, especially sodium and potassium. In severe cases, a lack of fluid and electrolytes leads to hemolytic uremic syndrome (HUS) in the further course. This involves the formation of small blood clots (thrombi) throughout the body. These block the blood supply to vital organs (e.g., brain, heart, kidneys). Kidney failure, coma and even circulatory failure are possible consequences.
Symptoms of bacterial dysentery at a glance:
- Violent, cramp-like abdominal pain (colic)
- Vomiting
- Painful urge to defecate
- Fever
- Watery to mucous-bloody diarrhea
- Ulcers in the intestine; intestinal bleeding; in severe cases, the intestine expands and ruptures (intestinal perforation) or the peritoneum becomes inflamed (peritonitis)
- Lack of fluids (dehydration), electrolyte loss
How does the doctor make the diagnosis?
The first point of contact when a Shigella infection is suspected is the family doctor. If necessary or for further examinations, he or she will refer the patient to a specialist or hospital. To diagnose shigellosis, the typical symptoms of the disease and a stool examination are usually sufficient.
To diagnose dysentery, the doctor first conducts a detailed interview (anamnesis) with the affected person. This is followed by a physical examination.
A visit to the doctor is necessary at the latest if severe diarrhea lasts longer than three days, is bloody or is accompanied by a fever above 38 degrees Celsius.
Talk with the doctor
Physical examination
The doctor then performs a physical examination. For example, he or she palpates the abdomen for indurations or checks for conspicuous bowel sounds with a stethoscope.
If shigellosis is suspected, the doctor makes the diagnosis on the basis of a stool sample from the affected person. For example, he examines the stool under a microscope to see whether there is an increased number of white blood cells (leukocytes).
Shigella can also be detected directly in the laboratory. There it can also be determined whether the type of Shigella bacterium detected has already developed resistance to a specific antibiotic (antibiogram). This tells the doctor whether a particular antibiotic is effective against the shigella or not.
Because shigella is very sensitive, it is recommended that a stool sample, as fresh as possible, be transported immediately to the laboratory in a special transport container.
How to treat shigellosis?
In most cases, the doctor treats an infection with shigella with antibiotics. These shorten the duration of the disease, reduce the excretion of the pathogens (and thus the risk of infection) and prevent complications. The active substances azithromycin or ciprofloxacin have proven to be particularly effective. The doctor administers the antibiotics in the form of tablets or, in severe cases, via an infusion.
Some shigella are resistant to certain antibiotics and are therefore insensitive to these drugs. In principle, doctors recommend treatment with antibiotics only after their effectiveness on the particular bacterium has been tested in the laboratory (antibiogram). This ensures that the antibiotic is actually effective against the pathogen.
If you are in good general health, it is possible in some cases to avoid antibiotic treatment. The doctor will assess whether this is possible in your case.
Antispasmodic agents
Supply of fluids and electrolytes
It is also important that sufferers drink enough to compensate for the loss of fluids due to diarrhea. If they cannot drink enough themselves, they receive infusions via a vein.
To replace lost minerals and salts (electrolytes) in the body, the doctor may likewise administer infusions or prescribe electrolyte solutions to drink from the pharmacy. If you do not have a medical supply or pharmacy near you while traveling, you can also prepare an electrolyte solution yourself in emergencies.
If you do not have juice in the house, you can use water or mild tea (e.g. chamomile or rosehip) instead. However, especially abroad, make sure that you use clean drinking water!
A homemade electrolyte solution is not intended to treat serious illnesses. If your child or baby is affected by diarrhea, if the diarrhea lasts longer than three days, or if there is blood in the stool, see a doctor immediately!
What is the course of dysentery?
The course of the disease varies depending on the type of pathogen. In Germany, infections mainly occur with Shigella sonnei (about 70 percent of cases) and Shigella flexneri (about 20 percent of those affected). These two types predominantly lead to milder illnesses, but start highly acutely and are usually very contagious.
As a rule, sudden symptoms such as watery diarrhea occur between about four hours and four days after infection. In some cases, fever, loss of appetite and abdominal pain also occur. In the milder, harmless forms, the symptoms disappear after about a week.
In rare cases, the bacteria settle permanently in the intestine and continue to be excreted in the stool. People in whom this is the case are called long-term excretors.
If the bacterium Shigella dysenteriae triggers the disease, the course of shigellosis is usually more severe. Often there is then bloody-mucous diarrhea accompanied by severe abdominal cramps. In addition, it is possible that ulcers form in the colon during the course of the disease, causing the intestine to expand or rupture in extreme cases (intestinal perforation).
How dangerous is dysentery disease?
However, severe and fatal complications of bacterial dysentery are rare. In this country, milder courses of the disease predominate, with infections often starting suddenly and violently and being highly contagious.
How long is one contagious?
Infected persons who have recovered and show no symptoms are still contagious for about four to six weeks. This is how long the pathogens can be detected in the stool of the affected person.
How can dysentery be prevented?
The best way to prevent dysentery is to wash your hands regularly and, above all, thoroughly:
- To do this, hold your hands under running water.
- Rub your hands thoroughly in all places (palms and backs of hands, fingertips, spaces between fingers and thumbs) with enough soap for at least 20 to 30 seconds.
- Then rinse your hands again under running water.
- Dry your hands carefully. Paper towels are suitable in public restrooms; at home, it is best to use a personal, clean towel.
If you do not have running water and soap available, use special disinfectant wipes, gels or sprays from the pharmacy. Make sure that your skin is dry and that you rub all areas thoroughly for about 30 seconds.
In addition, observe the following measures, especially in warmer countries with poor hygienic conditions:
- Do not drink tap water, but only water from original sealed drinking bottles.
- Cook or fry food before you eat it.
- Do not eat lettuce or fruit without the skin (e.g. grapes, strawberries). Instead, eat fruit with peel (e.g., bananas, oranges) and peel it yourself.
- Avoid swimming in shallow, warm water.
If you live in the same household with someone who has the disease, you should also pay attention to the following:
- Wash bed linen and towels at a temperature of at least 60 degrees Celsius.
- Regularly disinfect all objects with which the sick person has come into contact (e.g. remote control, light switch, door handles).
