SOME FACTS ABOUT MALARIA, 7 
After a time, even without treatment, the number of parasites may 
decrease until not enough of them are left to produce fever, in which 
case the patient improves temporarily. 
It generally happens, however, sooner or later, that the number of 
parasites increases again, and the patient again suffers from a series 
of attacks, 
Such relapses are frequently encouraged by fatigue, heat, chill, 
wetting, dissipation, or illness, and they may occur at intervals for a 
long time after the patient was first infected by the mosquito, and 
even after he has moved to localities where there is no malaria. 
Besides fever, these malarial parasites often produce anemia and 
enlargement of the spleen, especially with patients who have suf- 
fered many relapses. 
Death is often caused in malarial patients by other diseases, such 
as pneumonia or dysentery, the system being already weakened by 
the malarial parasites. 
If the patient survives, the parasites tend to die out of themselves, 
without treatment, after a long period of illness, leaving him more 
or less immune. 
The parasites are of at least three kinds, which can be easily dis- 
tinguished in the blood if placed under the microscope. These are 
(1) a parasite which produces its spores every three days and causes 
what is called quartan fever; (2) a parasite which produces its spores 
every other day and causes tertian fever; (3) parasites which cause 
the so-called malignant fever or pernicious malaria, which is of an 
irregular type and in which dangerous complications most frequently 
occur. 
Quinine kills the parasites when administered at the proper time; 
but generally it will not destroy all the parasites in the body unless 
it is given in sufficient doses and continued for several months. As 
long as a single parasite remains alive in the blood, the patient may 
be subject to relapses. Ross advises that at least 5 grains of sulphate 
of quinine should be taken by an adult patient every day without fail 
for four months, but he should consult a physician regarding the 
details of the treatment. 
METHOD OF INFECTION. 
The malaria parasite has several different stages. Aside from 
those forms which produce spores in the body, there are other 
stages—male and female. When one of these anopheline mosquitoes, 
which carries malaria, happens to feed on a patient whose blood con- 
tains parasites, these are sucked, with the blood, into the mosquito’s 
stomach. 
If the sexual forms of the parasites are present, those of opposite 
sexes at once unite. The parasite now undergoes certain changes in 
450 
