Ezek a paraziták rendkívül ellenálló, vastag falú oo cysták formájában kerülnek a környezetbe, ahol hosszú ideig megőrzik fertőzőképességüket.
A Commons projekt szabad licencű kép- és multimédiatár. Segíts te is az építésében! LeírásGiardia lamblia SEM lores. Once an animal or person has been infected with this protozoan, the parasite lives in the intestine, and is passed in the stool.
Because the parasite is protected by an outer shell, it can survive outside the body, and in the environment for long periods of time. Cysts are resistant forms and are responsible for transmission of giardiasis. Both cysts and trophozoites can be found in the feces diagnostic stages.
The cysts are hardy and can survive several months in cold water. Infection occurs by the ingestion of cysts in contaminated water, food, or by the fecal-oral route hands or fomites. In the small intestine, excystation releases trophozoites each cyst produces two trophozoites.
Trophozoites multiply by longitudinal binary fission, remaining in the lumen of the proximal small bowel where they can be free or attached to the mucosa by a ventral sucking disk. Encystation occurs as the parasites transit toward the colon.
Orv Hetil. The oocysts and cysts of these parasites excreted in faeces are capable of infecting other hosts and those are environmentally stable. AIM: The aims of the study were to evaluate the prevalence and genotypes of Cryptosporidium and Giardia species from different water sources as well as to monitor and characterize the oo cyst contamination sources in watersheds.
The cyst is the stage found most commonly in non-diarrheal feces. Because the cysts are infectious when passed in the stool or shortly afterward, person-to-person transmission is possible.
Giardia parasite causing human infections
While animals are infected with Giardia, their importance as a reservoir is unclear.