The best method to eliminate swimmer's itch is to:

Eliminating swimmer's itch effectively comes down to intervention in the life cycle of the pathogens causing it. Swimmer's itch is primarily caused by schistosome larvae entering the skin of individuals swimming in infested waters. The best approach to mitigate this condition involves breaking the life cycle of the schistosome.

Schistosomes require specific intermediate hosts, primarily freshwater snails, to reproduce and develop. By targeting the snail population or disrupting their habitats, the capacity for schistosomes to mature and produce cercariae (larval forms) that can infect humans would be significantly reduced. This breaks the cycle of infection at its source, leading to a decrease in occurrences of swimmer's itch.

While applying antibiotics to the water might address some bacterial infections, it does not have any effect on the schistosomes or their life cycle. Raising the pH might affect some aquatic organisms, but it's not a targeted method for addressing schistosomiasis. Destroying all aquatic vegetation could harm the ecosystem and does not directly interrupt the life cycle of the schistosomes, as these parasites can still reproduce without the complete elimination of vegetation.

Therefore, targeting the reproduction and life cycle of the schistosome through methods that affect its intermediate hosts presents the most effective