PROPHYLAXIS OF MALARIA. 
87 
In regard to malaria prophylaxis in semipermanent camps and 
permanent posts, the daily administration of the drug in the dose 
indicated, with the proper reductions in dose in women and children, 
will likewise be found the most efficient method: but if for any rea- 
V 
son this method can not be adopted, the administration of 1 gram 
(15 grains) on the evening of every third day should be preferred 
to any other of the interrupted methods of quinine prophylaxis. 
The reason for this is evident. It has been shown that all of the 
quinine taken at any one time is entirely eliminated within 72 hours, 
so that if an interrupted method of giving the drug is adopted it 
should be one in which there is no time when the blood is entirely 
free, and this can only be accomplished by selecting one in which 
the dose is repeated within 72 hours. While with the method advo¬ 
cated there will be a period of an hour or so in which the blood is 
free from quinine, this can be disregarded in practice. This method 
has the advantage also that it is easier to remember to take the dose 
of quinine every other day than at the fourth, ninth, and other days 
required by some of the methods of quinine prophylaxis already 
mentioned. The more simple we make our methods of prophylaxis 
the better they will succeed, especially with soldiers, and for this 
reason I do not favor the complicated methods advocated by some 
authorities in which quinine is to be taken at irregular intervals. 
The two methods outlined here will be found efficient in practice, 
the choice, if possible, resting with the daily administration of the 
drug. 
The administration of smaller doses of quinine than those advo¬ 
cated in the prophylaxis of malaria should be discontinued both 
because smaller doses are inefficient and because if there is any danger 
of the production of quinine-fast strains of the plasmodia they are 
much more apt to be produced by doses of 1 and 2 grains of quinine 
daily than by the amount recommended. Personally, I see no proof 
that such strains have ever been developed, and while the theory 
is fascinating, especially in the explanation of resistant infections 
and relapses, there is no scientific evidence that such forms of the 
plasmodia actually exist. Therefore, my objection to smaller doses 
of quinine than those mentioned is based almost entirely upon my 
conviction that such doses are insufficient to prevent infection and 
are practically useless in the prophylaxis of malaria. 
It should be distinctly understood that the dosage of quinine 
recommended to prevent malarial infections in the healthy has 
nothing whatever in common with that employed in preventing 
relapses in the infected or in the treatment of “carriers” of the 
infection. These subjects will be shortly referred to, but the ex¬ 
perience of Celli, in Italy, absolutely demonstrates that quinine 
