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upon it to daily contact with the malaria mosquitoes, it can be assumed that these men encoun- 
ter the maximum difficulty in avoiding infection. The fact that infection was prevented with- 
out any important personal inconvenience or serious interference with the field work has led 
to the idea that suggestions on “‘how to avoid contracting malaria” would be of interest to the 
field men of the bureau and others whose work necessitates spending all or a portion of the 
season in regions where malaria occurs. 
Malaria is not confined to any particular regions of the United States. It is more preva- 
lent in some regions than in others, but it may occur in any locality where suitable conditions 
exist for the development of the particular species of mosquitoes which act as the. conveying 
agents. It is to be suspected in any rural region during the season of higher temperatures 
where collections of surface water occur in any extent. 
When going to a new field station, or returning to a former station if the question has not 
been considered previously, a field worker should consult some well-informed physician of the 
region as to the prevalence of malaria in that region. It is important to determine the foci of 
the disease, the types of the disease, and the seasonal rate of the disease that obtain for that 
particular region. This information will enable the person to avoid unnecessary exposure 
in those localities where the disease is more prevalent, to recognize the disease from the symp- 
toms, and to know the seasons when particular care should be taken. The centers of infection 
should be avoided in the selection of living quarters and laboratory room. 
If the disease is contracted, it should be remembered that it is not a dangerous malady 
to combat under proper treatment but it is important to have the services of a well-informed 
physician. The most important point is the diagnosis. Many derangements of the system, 
aside from an infection of the malaria parasite, produce a chill, and very often a person experi- 
encing a chill when located in a region where malaria is prevalent is apt to diagnose his own 
case and pronounce it malaria. Very often under the impression that the disease has been 
contracted, or as a preventive, a more or less continued and irregular use of quinine is begun, 
which is seldom of benefit. Under no treatment at all the chronic type of the disease is apt to 
develop, and so it is important to learn as early as possible, if any of the symptoms of malaria 
develop, whether or not it is really malaria. The finding of the organism in the blood is the 
proper method of diagnosis. The physician will advise the proper treatment as to laxatives, 
quinine, and diet. There is one important point that it would be well to mention. The phy- 
sician will always advise but the patient will seldom take several days of complete rest after 
the malarial attack has been arrested. The impulse is to be up and about after the active 
symptoms of the disease have disappeared. The course of quinine should be continued after 
the chills cease, to obtain complete sterilization of the blood, and rest also is of decided assist- 
ance. 
A primary requisite in avoiding an infection of malaria is a clear understanding of the 
nature of the disease, of the causative organism, of the manner of its transmission, and of the 
mosquitoes that are the vectors. There are several publications of the Bureau of Entomology 
which provide this information. Bulletins 78 and 88 give the foundation of the subject. A 
special discussion of malaria is found in Farmers’ Bulletin 450, which also figures the malaria 
mosquitoes. A more concise arrangement of Bulletin 88 is found in Farmers’ Bulletin 444. 
In a malaria region the living quarters and the laboratory room should be properly screened 
with wire cloth. During the season when mosquitoes are active a person should always sleep 
under a mosquito bar or bed net, irrespective of whether the house or room is screened or not. 
If the house is screened already, attention should be given to its condition and to the size of 
the mesh. Not less than a No. 16 mesh should be used. The dealers do not carry this size 
mesh as a rule, but it should be insisted upon, as it can always be secured by them from any 
