Ever since I had a dog that has had it (cocker) and thankfully survived, and know 3 dogs that have died from it, and have just learnt today a dog locally has died from this it is at the forefront of my mind re monthly prophylaxis (I know some do worm counts but this is my choice re using wormers). Have also just learnt that the worming prophylaxis I use probably doesn't kill off as much as I think it should so am going to change my regimen re monthly wormers now