254 



MOSQUITOES OF NORTH AMERICA 



results than had been obtained at Laredo, the scale of operations at the same 

 time being very much greater. The presence of yellow fever in the city of New 

 Orleans was first recognized about the 13th of July, 1905. The plan of cam- 

 paign, adopted by the Board of Health under Dr. Quitman Kohnke from the 

 beginning, was based on the recognition of the mosquito conveyance of the dis- 

 ease and was directed against Aedes calopus. Dr. Kohnke had, in fact, for some 

 time previously, been one of the foremost physicians in the South to preach 

 mosquito destruction. For more than two years he had been doing everything 

 in his power to secure the screening of the numerous cisterns, and to induce the 

 city to adopt other necessary measures, but without success. Available funds 

 to combat the epidemic were rapidly exhausted, and on the 12th of August the 

 Public Health and Marine-Hospital )Service was put in charge of the situation 

 and provided with means. Dr. J. H. White, of the service, had complete com- 

 mand. By that time the increase in the new cases and deaths rendered it prac- 

 tically certain that the disease was as wide-spread as during the terrible epidemic 

 of 1878. There had been up to that time 142 deaths from a total of 913 cases, 

 as against 152 deaths from a total of 519 cases in 1878. The work for the rest 

 of the summer was continued with great energy under Dr. J. H. White, and the 

 measures were based almost entirely upon a warfare against the yellow-fever 

 mosquito. The disease began almost immediately to abate, and the result at 

 the close of the season indicated 460 deaths, as against 4046 in 1878, a virtual 

 saving of over 3500 lives. 



The following table of deaths from yellow fever in New Orleans from 1847 to 

 1905 points out strikingly the value of this anti-mosquito work : 



Comparative table of deaths from yellow fever in New Orleans during various 

 years. 



The epidemics of 1848, 1854, and 1855 are least comparable with that of 1905 

 because they immediately succeeded severe epidemics to which were due very 

 many immunes. 



The population of New Orleans by the United States Census was 130,565 in 

 1850; 168,675 in 1860; 191,418 in 1870; 216,090 in 1880, and 287,104 in 1900. 



