Abstract
We surveyed chlorine-resistant protozoa in 137 samples of sewage from 22 locations in Hyogo prefecture and Cryptosporidium and Giardia were detected microscopically. From FY2018 to FY2019 we conducted surveys selecting mainly in rural areas or residential areas that are not affected by livestock. In one area where drinking water was taken from a shallow well which is likely contaminated by surface water and supplied only by chlorination, Cryptosporidium was found twice. On the other hand, Giardia has a high background, probably due to infection caused by unknown factors, and its relationship with the water treatment plant was not detected.
