20 LOSS THROUGH INSECTS THAT CARRY DISEASE. 



of Havana, undertaken under the direction of Gorgas, with startling 

 results. 



Yellow fever had been endemic in Havana for more than one hun- 

 dred and fifty years, and Havana was the principal source of infec- 

 tion for the rest of Cuba. Other towns in Cuba could have rid 

 themselves of the disease if they had not been constantly reinfected 

 from Havana. By ordinary sanitary measures of cleanliness, im- 

 proved drainage, and similar means the death rate of the city was 

 reduced, from 1898 to 1900. from 100 per thousand to 22 per thou- 

 sand ; but these measures had no effect upon yellow fever, this disease 

 increasing as the nonimmune population following the Spanish war 

 increased, and in 1900 there was a severe epidemic. 



Stegomyia calopus was established as the carrier of the fever 

 early in 1901, and then antimosquito measures Avere immediately 

 begun. Against adult mosquitoes no general measures were attemp- 

 ted, although screening and fumigation Avere carried out in quarters 

 occupied by yellow-fever j)^tients or that had been occupied by 

 yellow-fever patients. It was found that the Stegomyia bred prin- 

 cipally in the rain-water collections in the city itself. The city was 

 divided into about 30 districts, and to each district an inspector and 

 two laborers were assigned, each district containing about a thousand 

 houses. An order was issued by the mayor of Havana requiring all 

 collections of water to be so covered that mosquitoes could not have 

 access, a fine being imposed in cases where the order was not obeyed. 

 The health department covered, the rain-water barrels of poor fami- 

 lies at public expense. All cesspools were treated with petroleum. 

 All receptacles containing fresh water which did not comply with the 

 law were emptied and on the second offense destroyed. The result of 

 this work thoroughly done was to Avipe out yellow fever in Havana, 

 and there has not been a certain endemic case since that time. 



In the New Orleans epidemic of 1905, a striking illustration of the 

 value of this recently acquired mosquito-transmission knowledge is seen. 

 The presence of yelloAv fever in the city was first recognized about the 

 12th of July, and the plan of campaign adopted by the Board of Health 

 under Dr. Quitman Kohnke, from the beginning was based on the 

 mosquito couAeyance of the disease. AA^ailable funds Avere rapidly 

 exhausted, hoAveA'er, and on the 12th of August the Public Health and 

 Marine-Hospital Service Avas put in charge of the situation and pro- 

 vided Avith ample means. By that time the increase in the ncAv cases 

 and deaths rendered it practically 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 sum- 

 mer Avas continued Avith great energy under Doctor White, and the 

 measures were based almost entirely upon a Avarfare against the yet- 

 loAv-fever mosquito. The disease began almost immediately to abate, 

 and the result at the close of the season indicated 460 deaths, as 

 against 4,04G in 1878, a virtual saving of OA-er 3,500 lives. The 



