The reference on schistosomiasis and Jerico is as follows:
Hulse, E.V. 1971. Joshua's Curse and the abandonment of ancient
Jerico: Schistosomiasis as a possible medical explanation. Medical
History. XV(4):376-386.
I found it to be a very interesting hypothesis. After all, some
people consider Joshua to be the first public health sanitary officer
A.K. Prestwood
Prestwood.A at calc.vet.uga.edu