MSD Manual

Please confirm that you are a health care professional

honeypot link
Pet Owner Version

Lung Flukes in Cats


Ned F. Kuehn

, DVM, MS, DACVIM, Michigan Veterinary Specialists

Reviewed/Revised Aug 2018 | Modified Oct 2022

The adult flukes Paragonimus kellicotti and Paragonimus westermani usually live in cysts or bulla, primarily in the lungs of cats. They also have been found rarely in other organs or the brain. Infection is most common in China, southeast Asia, and North America. The eggs from the adult flukes, are coughed up, swallowed, and passed in the feces. The life cycle includes several snails as the first intermediate host and crayfish or crabs as the second. Cats become infected by eating raw crayfish or crabs that contain the encysted parasite. The young flukes eventually migrate to the lungs where they become established.

Infected animals may have a chronic, deep, intermittent cough and eventually become weak and lethargic, although many infections pass unnoticed. A diagnosis is based on finding the characteristic eggs in feces or coughed-up material. The location of the flukes in the lungs is determined by x-ray. Several drugs provide effective treatment for lung fluke infections.

quiz link

Test your knowledge

Take a Quiz!