SCHISTOSOMES Meaning and
Definition
-
Schistosomes are a group of parasitic flatworms belonging to the class Trematoda. They are commonly known as blood flukes due to their ability to infect the blood vessels of vertebrate hosts. Schistosomes have a complex life cycle that involves two hosts: a definitive host, usually a mammal (including humans), and an intermediate host, typically a snail.
The adult schistosomes inhabit the blood vessels of the definitive host. They have separate male and female individuals, with males being smaller and residing in the gynecophoric canal of females. The females produce eggs that are released into the bloodstream and expelled through the host's excretory system, such as urine or feces. These eggs can contaminate freshwater environments, where they hatch into miracidia larvae.
Miracidia seek out a specific species of snail to infect and undergo further development within its tissues, resulting in the release of cercariae. The free-swimming cercariae then actively penetrate the skin of humans or other mammals that come in contact with the water. Once in the new host, the cercariae evolve into schistosomula, which migrate through various organs to reach the final location in the blood vessels.
Schistosomes cause a disease known as schistosomiasis or bilharzia, which affects millions of people worldwide, particularly in tropical and subtropical regions. The infection can lead to chronic inflammation, tissue damage, and various complications, including liver, kidney, and bladder problems. Treatment often involves the use of antiparasitic drugs, along with efforts to improve sanitation and control the snail hosts within susceptible areas.
Etymology of SCHISTOSOMES
The word "schistosomes" is derived from the Greek word "skhistos", which means "split" or "divided", and the Greek word "soma", which means "body". The term refers to a group of parasitic worms belonging to the class Trematoda, which have a characteristically flattened and elongated body shape.
