Pruning no. Thinning out the bed yes. Strawberries produce so many runners that you should be thinning out the bed every 3 years (do in August for June bearers). Thin by removing very old plants and too many young plants.

Another help is to use straw in the walkways which helps keep the fruit clean too from mud.

Perhaps also spray a fungicide like Captan? Especially if a wet spring?

Thanks, I am actually thinning them out - I said it wrong. A fungicide is a good idea hoping to stay organic.