That is how the cycle works and to break it, owners must treat adult dogs for worms every three months. As they are more likely to have worms, puppies should be treated every two weeks from the age of two weeks to twelve weeks and then every month until the age of six months. People who keep dogs must be responsible and clean up after their dog as well as make sure that their family practice good hand hygiene. This will reduce the risk of worms in dogs to other dogs and people.