Infection in the intermediate hosts
The adult tapeworms are large, segmented and as the name suggests are flat worms. Egg bearing segments of the worm called Proglottids are excreted in the human feces. If the excreted matter is not disposed properly and is left to mix in the water bodies and soil, then the water and soil gets contaminated. Subsequently, the intermediate hosts such as the pigs, cow, dog, rodents, sheep, cat, fish and other crustaceans, are infected with the eggs.
An intermediate host is one which is infected with a parasite that will not reproduce sexually within it while a definitive host is one in which the parasite reproduces within it. The eggs then hatch inside the intermediate host and the larvae invades the intestinal wall and gets to the blood stream and is carried to the other tissues of the animals where they develop into the cyst. When people consume the under cooked meat and fish, they also take in the cyst along with the food. The cyst then develops into the adult tapeworm. People with tapeworms can also reinfect themselves
