Abstract
A field research on occurrence of Cryptosporidium oocysts and Giardia cysts was conducted at Sagami river and its tributaries. In the first survey with presumptive test (screening survey), presumptive Cryptosporidium oocysts were found in 13 (81%) of 16 samples (9 (75%) of 12 sites), ranging from 1 to 2,500 oocysts·: 100l-1 and presumptive Giardia cysts were found in 15 (94%) of 16 samples (11 (92%) of 12 sites), ranging from 1 to 2,400 cysts·100l-1. In the second survey conducted at selected 6 sites with confirmed test, confirmed Cryptosporidium oocysts were found in 7 (70%) of 10 samples (4 (67%) of 6 sites), ranging from 3 to 4,500 oocysts·100l-1 and confirmed Giardia cysts were found in 9 (90%) of 10 samples (5 (83%) of 6 sites), ranging from 1 to 1,200 cysts·100l-1.
