A parasite is an organism that depends wholly on another organism which is the host just for it's survival.
These parasites can either be Ectoparasites as they are found on the host or Endoparasites as they are found within the body and tissues of their host.
The parasites damage their host tissues in so many ways which include the following
Parasites cause intestinal obstructions. An example is the Ascaris Lumbricoidis.
Intracellular parasites usually kill their host cells within which they multiply as seen in the destruction of Red Blood Cells by the plasmodium parasites.
The parasites cause damage through inflammation as a result of the rupturing of the parasitized cells.
Parasites cause irritation when found in large numbers.
Parasites cause mechanical pressures especially those that affect the Central Nervous System.
Parasites are also capable of causing vascular blockage. An example is Schistosoma.
Therefore we should try at all cost to terminate parasites around and within us in other to avoid these effect on us.