Giardia lamblia: protozoan cause of giardiasis

Cause of the disease

Giardiasis is an infection caused by the protozoan Giárdia lamblia, which can be either cyst or trophozoite.


This infection can occur in both adults and children, and can most often be asymptomatic. When you have symptoms, these are usually diarrhea and abdominal pain.

When infection with this protozoan becomes chronic, it usually presents with symptoms such as soft and fatty stools, bloating, flatulence, and anorexia (which can lead to weight loss and anemia).


Its form of infection occurs by direct or indirect contact with the feces of infected people. In its form of direct contagion, the hand is the main vehicle, as it transports and favors the ingestion of cysts in infected wastes. Indirect contamination occurs through ingestion of contaminated food and water.

Once inside its host, this parasite undergoes an incubation period that can last from one to four weeks. After this period, he may act in both asymptomatic (which is the most common) and symptomatic form. The most common complication caused by giardiasis is malabsorption syndrome.


The best way to prevent this infection is to take preventive measures such as drinking only filtered water, basic sanitation, washing hands thoroughly after using the toilet, washing in running water and sanitizing fruits and vegetables.

PLEASE NOTE: The information on this page is only for research and school work. Therefore, they should not be used for medical advice. To do so, see a doctor for guidance and proper treatment.