How does the infection of tapeworm in human, liver fluke in grazing animals like goat and sheep occur and what are their preventive measures?

Explanation

a. Infection of tapeworm in man :
Animals become infected with tapeworms while grazing in pastures or drinking contaminated water.
If human beings , consume raw or undercooked meat of such animals (e.g. beef, pork), they get infected.
Humans can also become infected if they consume food or water contaminated with the faeces of an infected person.
Preventive measures:
Maintain personal hygiene, careful washing of fruits and vegetables , adequate cooking of beef , pork, etc.
b. Infection of liver fluke in grazing animals lie goat and sheep :
Liver flukes are found i aquatic environments such as slow moving streams, irrigation channels, etc. Where they can lay their eggs. These eggs on hatching develop into larve which live in an intermediate host (usually snails) . The larve develop into cercaria in te body of snails which then swim in water until they find grassy vegetation and then form cyst-like metacercaria. When such grass is eaten by grazing animals like goat and sheep , the cyst enters their intestine and then migrates into the liver and further develops and matures into an adult in their bile duct.
Preventive measures :
Management techniques such as fencing the areas that harbour the snails, draining wet areas of pasture or grazing in drier pastures, avoiding snail infected areas for grazing animals, etc.