Originally Posted by juro
Are there precautions people should take with felt soles to prevent spreading parasites from river to river?
thanks in advance
Certainly, and not only felt soles, but all items of tackle, should be disinfected. Canoes and the like must also be regarded as potential vectors. Thorough drying for 7 days is normally regarded as sufficient, but if there is any doubt, soaking in a solution of something like Virkon is normally suggested.
Here's an example from the River Tweed Commissioners of a declaration that fishermen may be asked to sign. There's some general information on this document, but googling gyrodactylus will no doubt give you more detail.