[Cryptosporidium parvum and Giardia lamblia--incidence in surface and drinking water--significance and detection].

Cryptosporidium parvum and Giardia lamblia are protozoan parasites which can cause gastroenteritis in man and animal. Surface water and drinking-water play an important role in transmission of the disease. The parasites can be detected by extensive and time-consuming procedures only. In this paper we describe a new way to isolate C. parvum and G. lamblia from water by a modification of essential steps of the original method of Rose. The new method applies the separation by flow centrifugation, the purification by different filters and the parasite isolation by percoll density gradient centrifugation. The modified method allows reproducible and by 20% increased recovery rates of cysts. Due to this fast and easy technique this procedure can be integrated in routine examinations.