... diurnal profiles of Cryptosporidium and Giardia, representative waterborne infectious protozoans, in river water which is used for drinking water sources in Japan. To investigate the annual profiles, ... River X Treated sewage wastewater Sampling sites for investigating annual profiles Sampling sites for investigating diurnal profiles Site A River flow Site B Site E Koyama River Site F Site G Site ... one sampling site in which the frequency of detection was extremely low. To investigate diurnal profiles, 15 river water samples were collected at 3 sites in the tributary rivers of the Tone River...