infections
Overview of Fluke Infections
Introduction
Flukes are parasitic flatworms. There are many species of flukes. Different species tend to infect different parts of the body. Flukes may infect species ( Schistosomiasis ) , and related organisms ( Fluke Infections of the Intestines ) species ( Fluke Infections of the Liver ) and related species ( Fluke Infections of the Lungs ) Thelife cycle of flukesis complex. It typically involves snails that live in fresh water. Infected snails release immature flukes that swim in the water (cercariae). In some species of flukes, the cercariae directly infect people who come in contact with them in the water. In other species, the cercariae first infect fish or crustaceans (such as crayfish or crabs) and form cysts in their flesh. Some flukes form cysts on aquatic plants. If people eat raw or undercooked fish or crustaceans or aquatic plants that contain the cysts, they can become infected. Flukes mature into adults in people. Depending on the species, adult flukes may live from 1 to more than 20 years. Adult flukes release eggs. Eggs that are released into the digestive tract can be passed in stool. Eggs that are released into the urinary tract can be passed in the urine. If untreated stool or urine enters fresh water, the eggs hatch and infect snails, continuing the fluke life cycle. Symptomsvary depending on which organ the adult flukes infect. Diagnosisof fluke infections usually involves examining a sample of stool, urine, or sputum with a microscope to look for characteristic eggs. Sometimes blood tests are done. Fortreatment,praziquantel, a medication that eliminates flukes from the body, is effective for most, but not all fluke infections in people. Preventionof fluke infections is very important. People living in or visiting areas where flukes are common should avoid contact with contaminated freshwater and dispose of urine and feces in a sanitary way. (See also Overview of Parasitic Infections .) 