Capillaria is a roundworm that resides in the lung of dogs and foxes. Infection is by ingestion of contaminated feces. The developing larvae migrate directly to the lungs. Adults lay eggs in the lungs which are moved out the lungs and coughed up, reswallowed and passed in the feces. Ivermectin may play a roll in treatment but, currently there is no recommended therapy Paragonimus is an infrequent parasite of the dog that exists almost exclusively in the most northern areas of the Midwest and north central Canada.
Transmission is by consumption of freshwater crustaceans and snails, acting as an intermediate host.
The disease is serious only when the parasite gets into the brain. There is no recommended therapy. Prevention is by eliminating the consumption of freshwater crustaceans and snails. Nanophyetus salmincola is a small intestinal fluke acquired by dogs when they consume raw salmon from the northwest. The disease exists only in the northwest.