MOSQUITOES AND MALARIA. 9 
the valley of the Po and elsewhere. The introduction and spread of 
malaria in Greece is stated by Ronald Ross, and with strong reasons, 
to have been largely responsible for the progressive physical degen- 
eration of one of tin' strongest races of the earth. 
In tin 1 United States, malaria, if not endemic, was early introduced. 
The probabilities arc that it was endemic, and it is supposed that the 
cause of the failure of the early colonies in Virginia was due to this 
disease. It is certain (hat malaria retarded in a marked degree the 
advance of civilization over the North American Continent, and 
particularly was this the case in the march of the pioneers through 
out the Middle West and throughout the Gulf States west to the Mis- 
sissippi and beyond. In many large regions once malarious the disease 
has lessened greatly in frequency and virulence owing to the reclama- 
tion of swamp areas and the lessening of the numher of the possible 
breeding places of the malarial mosquitoes, hut the disease is still 
enormously prevalent, particularly so in the southern United State-. 
There are many communities and many regions in the North where 
malaria is unknown, but in many of these localities and throughout 
many of these regions Anopheles mosquitoes breed, and the absence 
of malaria means simply that malarial patients have not entered these 
regions at the proper time of the year to produce a spread of the 
malady. It has happened again and again that in communities where 
malaria was previously unknown it has suddenly made its appearance 
and spread in a startling manner. These cases are to be explained, 
as happened in Brookline, Mass., by the introduction of Italian labor- 
ers some of whom were malarious, to work upon the reservoir; or, 
as happened at a fashionable summer resort near New York City, by 
the appearance of a coachman who had had malaria elsewhere and 
had relapsed at this place. In such ways, with a rapidly increasing 
population, malaria is still spreading in this country. 
To attempt an estimate of the economic loss from the prevalence 
of malaria in the United States is to attempt a most difficult task. 
Prof. Irving Fisher, in one of his papers before the recent Inter- 
national Tuberculosis Congress, declared that tuberculosis costs the 
people of the United States more than a billion dollars each year. 
In this estimate Professor Fisher considered the death rate for con- 
sumption, the loss of the earning capacity of the patients, the period 
of invalidism, and the amount of money expended in the care of the 
sick, together with other factors. In making these estimates he had 
a much more definite basis than can be gained for malaria. The 
death rate from malaria (as malaria) is comparatively small and is 
apparently decreasing. Exact figures for the whole country are not 
available. From a table comprising 22 cities it appears that two- 
thirds of the deaths from malaria in the United States occur in the 
South — one-third only in the North. The death rate from malaria 
83434— Bull. 78—09 2 
