Malaria
A parasitic infection occurring mostly in the tropics and subtropics.
Malaria is caused by a protozoan parasite of the genus Plasmodium,
which requires two different hosts during its life cycle:
man and mosquito. It is transmitted from man to man by the bite
of an infected mosquito. The mosquito sucks blood from an infected
person, taking in the parasite - which can then continue its
life cycle within the mosquito. Later, when the mosquito bites
another human, the parasites pass in with the insect's saliva.
Once inside man, the parasites continue to develop in the
liver. From there they reenter the bloodstream and multiply
inside red blood cells, causing them to rupture within two or
three days. This rupture of the red cells is responsible for
the characteristic chills, fever and sweating of malaria. Parasites
released into the bloodstream when the cells rupture can enter
other red cells, and the life cycle is repeated.
Definition
from Family Medical Encyclopedia -
Published in 1984 by Book Club Associates
