Giardiasis - diarrhea caused by parasites
Synonyms
Giardiosis, lamblia dysentery
What is giardiasis?
Giardiasis is a common infectious diarrheal disease caused by the parasite Giardia lamblia.
This parasite occurs worldwide and is mainly transmitted through poor food hygiene through ingestion of contaminated water or food. Giardiasis is also known under the name Lamblienruhr.
It usually causes uncomfortable, long-lasting diarrhea, but in most cases it is not life-threatening.
Causes of Giardiasis
The common diarrheal disease giardiasis, which is caused by the parasite Giardia lamblia, is in most cases transmitted through poor food hygiene. Giardiasis can affect not only humans, but also animals.
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- Giardiasis in the dog
- Giardiasis in the cat
In its infectious form, it is excreted in the stool as a cyst. It can happen that bodies of water or even food are contaminated with the pathogen. Thus, the parasite can easily be transmitted by drinking contaminated water or eating contaminated food.
If there is insufficient hygiene after using the toilet, the infection can also be passed on.
The parasite occurs all over the world, but is more common in the tropics and subtropics due to poorer hygiene measures. Therefore, especially giardiasis also affects those returning to travel.
Also read: These are the causes of diarrhea
How contagious is giardiasis?
The Giardia lamblia parasite comes in two forms. Once as an active throphozoite and once as an infectious cyst. Affected people and animals excrete the parasite in its cyst form with the stool.
The cysts can remain in the stool for weeks to months. This means that giardiasis is contagious for a long time through the stool. About ten cysts are enough for the parasite to be transmitted. Therefore, good hand and food hygiene should be observed.
Detecting giardiasis
Symptoms of Giardiasis
The symptoms of acute giardiasis typically include:
- Oily, frothy diarrhea
Since an infection with Giardia lamblia affects the small intestine, proteins and fats can no longer be sufficiently absorbed into the body from food. They stay in the stool, making it appear greasy and frothy. - Crampy abdominal pain
The parasite can also affect the gallbladder. In this case, there is usually cramping abdominal pain in the upper abdomen. - Flatulence
- Loss of appetite, nausea
- Vomit
These symptoms can usually last two to three weeks. However, they can then become chronic and cause existing, recurring diarrhea. This can be associated with deficiency symptoms and weight loss.
An infection with this parasite can also proceed without any symptoms.
Worms in the intestines can also cause similar symptoms. Read more about this at: Worms in the intestines
Diagnosis of giardiasis
In most cases, people affected with diarrhea do not get a diagnosis with a comprehensive search for the pathogen. Because in most cases the diarrhea will stop by itself.
However, if it turns out in the doctor-patient conversation that the person concerned has been abroad, pathogen diagnosis is often considered.
For this purpose, a stool sample from the patient is examined microscopically for cysts on up to three different days. If no cysts are found in the stool, but the person concerned does not respond to the therapy and continues to have diarrhea, a colonoscopy with samples taken from the intestine is recommended. Here you can detect the Giardia lamblia in its active form as a trophozoite.
Also read: This is how a colonoscopy works
Treatment of Giardiasis
Giardiasis is usually treated with the antibiotic metronidazole, even if it is not a bacterium but a parasite. The metronidazole works quite well against both manifestations (trophozoite, cyst) of Giardia lamblia. It should be taken in any case, even if the giardiasis is symptom-free. Because all infected people are contagious through the chair. The risk of infection can be minimized with metronidazole.
It is also recommended to start the therapy very early in order to avoid chronification and thus persistent diarrhea.
If the infected person has got a lot of fluids from the diarrhea, the doctor should give them a special solution with electrolytes to compensate for the fluid and electrolyte loss.
Read more about the antibiotic used at: Metronidazole
Course of disease and duration of giardiasis
Giardiasis can run completely without symptoms, which is why it is not noticed by the infected.
However, there are symptoms such as diarrhea, abdominal pain. Nausea and vomiting, they usually last for about two to three weeks. However, the infection time lasts much longer, as the parasite can be excreted in its cyst form through the stool for several weeks to months.
Appropriate antibiotic treatment can reduce the duration of infection and contagion.
Also read: Duration of diarrhea
Giardiasis prognosis
The prognosis for giardiasis is very good in most cases. Thus it is a harmless infection with parasites.
In rare cases, children or immunocompromised children can suffer damage to the small intestine with impaired absorption of nutrients. In this case, deficiency symptoms and growth disorders can occur.
