Aelurostrongylus abstrusus is the lungworm within this genus that causes verminous bronchitis or pneumonia in cats.
This "cat lungworm" is found in branches of the pulmonary artery where eggs are laid and hatch. The larvae break into the alveoli and ascend the air ducts to the mouth where they pass out with sputum or are swallowed and passed with the feces.
The larvae develop in the infective state in various terrestrial mollusks. Excessively infected cats display coughing, diarrhea, and emaciation.