Parasite Profile Lung Fluke

The Lung Fluke is a parasitic worm that causes paragonimiasis. The scientific classification for the Lung Fluke is paragonimus westermani. The worm ranges from three tenths to one half inches in length.

The life cycle of the Lung Fluke begins when the eggs hatch into larvae. They then infect water snails. When the larvae leaves the snails, they go on to infect freshwater crabs and crayfish.

The Lung Fluke can be found in Japan, the Philippines, China, Indonesia and also in some parts of South America and Africa. The Lung Fluke gets into the human body when people eat crabs or crayfish that are undercooked. Once inside the body, the Lung Fluke causes small cysts that have fibrous walls. When the cysts rupture they release the eggs of the worm. The worm is then coughed out of the lungs and into other parts of the body. Some of the Lung Fluke worms will leave the body along with feces. They can then infect other shellfish and people. That is how the life cycle of the worm continues.

Once the Lung Fluke worm gets into the lungs it covers itself with a granulation tissue. A capsule forms around the worm. The capsule will eventually ulcerate and then heal. If the worm gets into the spinal cord, paralysis can result. If the worm makes its way into the heart it can be fatal.

The paragonimiasis infection looks a lot like tuberculosis. The symptoms include bronchitis, with a severe cough and coughing up blood. In the case of heavy infections, lesions can form in the lungs, liver and brain. 

The infection can be diagnosed by testing the saliva or the feces of the individual. Lung Fluke eggs will show up in these tests.

The medication used against the Lung Fluke worm is called bithionol. It slowly kills the parasite. Recovery will be gradual as the worms and the eggs must be destroyed. Once the parasite is in the system, medication should be given until the Lung Fluke has gone through at least one entire life cycle.

To prevent the Lung Fluke worm from getting into the body, it is important to always cook shellfish thoroughly. This will kill the larvae. The internal temperature of the cooking shellfish should be a minimum of 165 degrees for at least ten minutes. Using a cooking thermometer to check this is advisable.