The ova of capillaria aerophila look like trichuris but are asymptomatic and slightly smaller. Capillaria aerophila is a nematode parasite found in the respiratory tract of foxes, dogs, and various other carnivorous mammals. A few cases of human infestation have also been reported. Though it is sometimes called a "lungworm", this term usually refers to other species of nematodes.
Infestation by C. aerophila is referred to as "pulmonary capillariasis" (occasionally spelled "capillariosis), "bronchial capillariasis," or (rarely) "thominxosis." This parasite has a direct life cycle, meaning that the life cycle can be completed in a single host. C. aerophila usually causes only minor clinical symptoms, such as irritation of the respiratory tract and coughing.
