Giardiasis
Giardiasis is a protozoan disease with various forms of progression: asymptomatic and manifest, with spontaneous elimination of parasites or elimination occurring only after specific therapy; prolonged persistence of parasites is possible, often difficult to treat with specific therapy.
The ability of Giardia to cause gastrointestinal tract dysfunction, the existence of epidemic outbreaks of diarrhea caused by Giardia, as well as the presence of complicated forms of infection, especially in individuals with common variable immunodeficiency (CVID), have allowed Giardia to be associated as a pathogen causing human disease.
Source: "Prevention of Giardiasis. Methodological Guidelines. MU 3.2.1882-04"
(approved by Rosconsumnadzor on March 3, 2004)