One of the most significant publications in recent years was issued in 1908 by the Merchants' Association of New York City on the pollution of New York Harbor. The fecal matter of the sewerage discharge into the water attracted swarms of flies, many of which were caught in traps placed on the piers and afterward examined in the laboratory for bacteria. One individual fly carried more than 100,000 fecal bacteria. The same publication contains a chart sbowing the location where each individual death from intestinal diseases occurred during the season, and they were by far the most prevalent in the downtown districts near the water front, where sewerage and fly conditions are worst. Infantile diarrhœa was the cause of many of these deaths, and the author of this publication, Dr. Jackson, attributes much of the infection to the agency of flies.
Washburn only last year investigated a typhoid outbreak, and found flies chiefly responsible for the spread of this disease on the Iron Range of Minnesota. Many other cases might be cited.
Local Conditions to be Avoided
Many persons go from their homes in the cities to spend their vacations at shore resorts or mountain camps, and are soon taken sick with typhoid. The imperfect sanitary conditions at many of these places make it hard to prevent the spread of the disease if a case of it occurs, and where a large number of persons are brought together from different localities there is always danger.
Large gangs of laborers in quarries, lumber camps and on construction work are, on account of carelessness and ignorance, liable to suffer from the spread of typhoid fever by flies, and what has been said of typhoid would doubtless be equally true of cholera and dysentery.
In looking about our cities and towns for breeding places of the house, fly, what do we find? In many stables manure is allowed to accumulate untreated as long as there is room for it, then it is carted away to the suburbs and piled upon the land. Carloads of manure from the large cities are drawn through our towns and allowed to stand on sidings for several days, perhaps, before reaching their destination and being unloaded. Streets are often so filthy as to attract flies, and when cleaned, the sweepings are dumped on vacant lots or drawn into the parks for fertilizer and allowed to remain in heaps several months. In many streets water closets are not installed, and uncared-for dry closets are still in use. All of these conditions are favorable for the breeding of flies, and we should remember that in
- D. D. Jackson, "Pollution of New York Harbor," Merchants' Association of New York, July, 1908.
- F. L. Washburn, Eeport of State Entomologist of Minnesota, 1909-1910, p. 135. See also Popular Science Monthly, August, 1911, p. 137.