[The significance of Giardia lamblia for water hygiene]

This paper gives a literature review about Giardia lamblia, an unicellular infectious agent, which is responsible for parasitic intestine-diseases. Morphologically, life-cycle, occurrence and caused symptoms of illnesses are described. The content of this publication is the question about the meaning of the importance of the pathogenic agent for water-borne epidemics. During the past 15-20 years the number of cases of water-transmitted giardiasis has increased enormously, especially in the USA, but in other countries, too. Modes of transmission of drinking-water supplied with surface-water are the origins as a rule. The set of problems becomes more interesting, because in Hungary cysts of Giardia lamblia in drinking-water were isolated recently. In this context it is to refer to the not unimportant number of unspecific diarrhoea with obscure origin in general. That's why it is necessary to value Giardia lamblia under the conditions of using surface-water for drinking-water as a potential water hygienic factor of risk.