If by hydrophobia, you are referring to Rabies Encephalitis, then in suburban areas where humans come in close contact to vectors such as raccoons, feral dogs, bats, foxes, etc.
Canada
Hydrophobia, or fear of water, can be prevalent in individuals with specific phobias or anxiety disorders. It is not limited to any specific geographical location but can be found worldwide in individuals with such conditions.
Osteoarthritis of the knee joints, is the most prevalent degenerative disease, probably, in USA.
hydrophobia
Rabies
it is caused by street virus .
The most prevalent diseases are 1) heart disease, 2) cancers, and 3) strokes.
"Hydrophobia" is a noun, the name of a disease.
Heart disease can take several forms but the most prevalent is coronary heart disease, in which the blood vessels that supply the heart with oxygen become blocked and the heart muscle becomes increasingly stressed.
walrus
They get vicious and if they scratch or bite you. You will get crazy, so avoid this disease.