6 SOME FACTS ABOUT MALARIA. 
of the Liverpool School of Tropical Medicine, who was the first dis- 
coverer of the relation between malaria and mosquitoes, something 
over 12 years ago, in India. His results were soon confirmed by 
workers in many parts of the world, and the statements here made 
are accepted by the best physicians of all countries. 
THE DISEASE AND ITS CAUSE. 
The disease known as malaria, or fever and ague, or chills and 
fever, or marsh fever, and the varieties called intermittent fever, 
remittent fever, and pernicious fever, are caused by parasites in the 
blood which feed upon the red blood cells. 
Malaria occurs more or less in all warm climates, especially in the 
summer after rains and near marshy ground. It is said to cause one- 
fourth or more of all the sickness in the Tropics. 
The parasites in the blood are microscopic one-celled animals 
called plasmodia. 
These minute parasites are introduced into the blood through the 
proboscis of certain mosquitoes of the genus Anopheles. 
On being introduced in this way, each parasite enters one of the 
red blood cells, in which it lives and grows. 
When full grown, each parasite divides and thus produces a num- 
ber of spores, which escape from the blood cell and enter fresh cells. 
This method of propagation may continue for years. 
Although only a few of the parasites may have been introduced 
originally through the beak of the mosquito, they rapidly increase 
until millions upon millions of them may exist in the blood. 
At first, when the number of parasites is still small, an infected 
person may remain apparently well. When, however, the number 
is large enough, he begins to suffer from fever. 
The parasites tend to produce their spores all at the same time, 
and it is at the moment when these spores escape from the blood 
cells, almost simultaneously, that the fever begins. 
The fever is probably caused by a little poison which escapes from 
each parasite with the spores. 
After from 6 to 40 hours or more this poison is eliminated from 
the patient’s system and his fever tends to leave him. 
In the meantime, however, a new generation of parasites from 
the spores is approaching maturity; and when this is reached they 
in their turn break up and cause another attack of the fever like the 
first, and so on indefinitely for months and months. In this way the 
attacks of the fever follow each other at regular intervals. 
But it often happens, as the result of repeated infections, that a 
new attack has commenced before the former one has ceased, so that 
they overlap and the fever continues. 
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