Bather density and levels of Cryptosporidium, Giardia, and pathogenic microsporidian spores in recreational bathing water.

The study demonstrated that the resuspension of bottom sediments caused by bathers and their direct microbial input resulted in elevated levels of Cryptosporidium parvum oocysts, Giardia lamblia cysts, and microsporidian spores, particularly Enterocytozoon bieneusi, in recreational beach water on days deemed acceptable for bathing by fecal bacterial standards.