PROPHYLAXIS OF MALARIA. 
95 
than acute infections, and I believe that I am safe in stating that 
every one of them can be cured if properly treated. 
So far as prophylaxis is concerned, the object of treatment in 
latent infections in which only the forms of plasmodia belonging to 
the human life cycle occur, is to prevent the individuals harboring 
these forms from becoming carriers of malaria, as they will be if 
gametes are allowed to develop. As these individuals are not infec¬ 
tive to mosquitoes, because gametes have not yet developed, there is 
no necessity for isolating and screening them, and as they present 
no symptoms the treatment may be pursued while they are attending 
to their ordinary avocations. In the case of soldiers it is not neces¬ 
sary to relieve them from duty, provided arrangements can be made 
for them to receive treatment at stated intervals under the direct 
supervision of a medical officer, so that* the treatment of these infec¬ 
tions need not interfere materially with military duties nor seriously 
deplete the strength of the command. It goes without saying that 
the discovery and treatment of latent malarial infection, so far as 
the military service is concerned, must be confined to semipermanent 
camps and permanent posts, as these measures would be imprac¬ 
ticable in active service in the field where protection from malaria 
must depend upon quinine prophylaxis, the use of the mosquito net, 
and other measures for protecting the men from the bites of these* 
insects. 
While in civil life the treatment of latent infections due to the 
tertian and quartan plasmodia differs from that of infections due 
to the estivo-autumnal plasmodia, in that smaller doses of quinine 
are used for the former infections, it will be better in the military 
service to adopt a scheme of treatment that will cure all cases and 
that can be easilv remembered by the individuals concerned. The 
following treatment of latent infections in which gametes are not 
present in the blood , while it may err upon the side of slightly too 
much quinine in the case of tertian and quartan malaria will be 
found efficient in infections due to the estivo-autumnal plasmodia. It 
should therefore be adopted if a single rule of treatment of all latent 
cases is to be followed, and this would appear to be the ideal method 
in the case of troops. This method of treatment is as follows: 
Every individual showing plasmodia in the blood (unless gametes 
are present) should receive 2 grams (gr. 30) of quinine daily until 
the plasmodia have disappeared from the peripheral blood. In most 
instances this will occur within three or at most four days. After 
the plasmodia have disappeared quinine should be given in daily 
doses of 1 gram (grs. xv) for two weeks, and for two weeks there¬ 
after a daily dose of 0.65 gram (grs. x) should be administered. 
After this the usual prophylactic dose of 0.40 gram (grs. vi) should 
be given daily for at least two months. 
