[The detection of Giardia lamblia in water].

Conditionally, especially by using surface-water for drinking-water, G. lamblia must be regarded as a potential water-hygienic factor of risk. A review is given about the main methods for detecting the parasite in water. A successful one, worked out by Borsod Megyei Köjál, Miskolc (Hungary), is presented. The base is membrane filtration. A continuing concentration of the cysts is obtained by centrifugation and zinc-sulphate flotation. The diagnosis is realized microscopically. It is possible to conclude the number of viable infections cells and the hygienic dangerousness potential in the analyzed water resources from the examination of the ability of the isolated cysts to change themselves into the vegetative form of the agent under laboratory conditions.