TRANSMISSION OF YELLOW FEVER BY MOSQUITOES. 059 



was suffered by tliem (with the exception of only one case, that of a youth wh(j wa« 

 lost sight of after the inoculation). 



Cases. 



Cases. 



Result unknown in 1 Five years in \ 2 



Less than one year in 11 Six years in ""'.'" 8 



One year in 3 Seven to ten years in 9 



Two years in 12 



Three years in 14 Total 87 



Four years in 28 



The yellow-fever patients upon whom the mosquitoes were contaminated were, 

 almost in every instance, well-marked cases of the albuminuric or melano-albumi-. 

 nuric forms, in the second, third, fourth, fifth, or sixth day of the disease. In some 

 of the susceptible subjects the inoculation was repeated when the source of the con- 

 tamination appeared uncertain. 



Among the 87 who have been under observation, the following results have l)een 

 recorded. 



1. Within a term of days, varying between five and twenty-five after the ino(-ula- 

 tion, 1 presented a mild all)uminuric attack, and 13 only "acclimation fevers." 



While Finlay's theory appeared to be plausible and to explain many 

 of the facts relating to the etiology of yellow fever, his experimental 

 inoculations not only failed to give it substantial support, but the nega- 

 tive results, as reported by himself, seemed to be opposed to the view 

 that yellow fever is transmitted by the mosquito. It is true that he 

 reports one case which "presented a mild albuminuric attack,'' which 

 we may accept as an attack of yellow fever. But in v-iew of the fact 

 that this case occurred in the city of Havana, where yellow fever is 

 endemic, and of the 86 negative results from similar inoculations, the 

 inference seemed justiiied that in this case the disease was contracted 

 in some other way than as a result of the so-called "mosquito inocula- 

 tion." The 13 cases in which "only acclimation fevers" occurred 

 " within a term of days varying between five and twenty-five after the 

 inoculation" appeared to me to have no value as giving support to 

 Finlay's theory; first, because these "acclimation fevers "could not 

 be identified as mild cases of yellow fever; second, because the oi-di- 

 nary period of incubation in yellow fever is less than five days, and 

 third, because these individuals, having recently arrived in Havana, 

 were liable to attacks of yellow fever or of "acclimation fever" a.s a 

 result of their residence in that city and quite independently of Doctor 

 Finlay's mosquito inoculations. For these reasons Doctor Finluy s 

 experiments failed to convince the medical profession generally of the 

 truth of his theorv relating to the transmission of yellow fever, and 

 this important question remained in doubt and a subject of contro- 

 versy. One partv regarded the disease as personally contagion,^ and 

 supposed it to be "communicated directly from the sick to the well a.s 

 in the case of other contagious diseases, such as smallpox, scarlet 

 fever, etc. Opposed to this theory was the fact that m uuunneral)le 

 instances nonimmune persons had been known to care for yellow- 

 fever patients as nurses or physicians without contracting the disease; 



