MEDICINE, ADVANCES IN. 



375 



companied by men with oil-cans, who covered 

 the surface of all puddles and cesspools about 

 the dwellings, and destroyed all the receptacles in 

 which mosquito larvae were found. After a suf- 

 ficient time for compliance with the new rule 

 was thought, to have elapsed all persons on whose 

 premises larvae were found were fined. Fifty men 

 were employed in this work, and 100 men in the 

 suburbs killing larvae and filling up puddles. 



Coincident with these out-of-door measures all 

 hospitals where yellow fever was received were 

 ordered thoroughly screened. In cases occurring 

 in private houses the house was screened by the 

 health department. All infected buildings were 

 thoroughly disinfected with pyrethrum powder; 

 this drug stupefies the mosquitoes, which fall to 

 the floor, and may then be swept up and de- 

 stroyed. 



This was used in preference to more powerful 

 substances, because of its harmlessness to furni- 

 ture, hangings, etc., and the short time required 

 before the rooms are again ready for occupancy. 

 Forty men were employed in this work. One 

 hundred and ninety men were used in enforcing 

 the new regulations as against 300 during the 

 previous year. 



In January, 1901, there were 24 cases of fever, 

 with 7 deaths; in February there were 8 cases 

 and 5 deaths. The new regulations were put in 

 force on Feb. 27. In March there were 2 cases, 



Bin April 3, in May 2, and in June none at all. 

 On July 1 all disinfection of so-called fomites 

 infected clothing, bedding, etc., was entirely dis- 

 continued. In July there were 4 cases and 1 

 death, in August 6 cases and 2 deaths, and in 

 September 1 case. During October, November, and 

 December there were none whatever. October and 

 November have always been months when yel- 

 low fever was particularly rife in Havana. There 

 is good reason for believing that the cases after 

 those occurring in May were due to infection from 

 a neighboring suburb, where a yellow-fever epi- 

 demic was in progress. 



In the first ten months following the enforce- 

 ment of the new regulations there were only 17 

 cases of yellow fever, as against something like 

 1,200 during the corresponding months of the pre- 

 vious year. As Dr. Gorgas says, " this is evi- 

 dence of the practical demonstration of the mos- 

 quito theory." 



On Nov. 6, 1902, he \vas able to say, before the 

 New York Academy of Medicine : " It is now over 

 a year since the last case of yellow fever occurred 

 in Havana, and if the disease can be kept out 

 of the city for twenty years, I think yellow fever 

 . will be completely exterminated in North Amer- 

 ica, for Havana has been the great center of in- 

 fection." 



The later Vera Cruz Yellow-Fever Commission 

 has entirely confirmed the findings of the United 

 States Army Commission in Havana. They at- 

 tributed the prevalence of the disease in Vera 

 Cruz to the custom of the Mexicans of gathering 

 rain-water for drinking purposes, and allowing 

 it to stand about unprotected. War on these 

 water-barrels has reduced yellow fever in the 

 city over 50 per cent. 



Sanitary measures directed against malaria 

 based on the mosquito theory have furnished 

 equally convincing results. 



The importance of the practical demonstration 

 of the truth of these startling theories it is hard 

 to overestimate. It may in many sections even- 

 tually lead to a large increase of real-estate val- 

 ues, and prove to have an important bearing in 

 determining the feasibility of large engineering 

 enterprises in tropical countries. The one prac- 



tically insurmountable difficulty in the construc- 

 tion of the Panama Canal has been the health of 

 the men employed. The work on this underta- 

 king, and also on the isthmian railway, was 

 stopped many times simply by the " dying off " 

 of all the workmen. So that it may be fairly said 

 that the building of the isthmian canal is " more 

 a sanitary than an engineering problem." The 

 two scourges of the isthmian country are malaria 

 and yellow fever, and both of these diseases are 

 now preventible, or at any rate can be controlled 

 and kept within narrow limits by the use of mos- 

 quito-netting. Many sections of country in 

 Africa and India are now practically uninhabit- 

 able because of malarial fevers, and whole dis- 

 tricts in Ceylon have been almost depopulated by 

 malaria; and even in this country in many sec- 

 tions the mosquito is an effective agency in pre- 

 venting the growth of population and real-estate 

 values. The vexatious and expensive methods of 

 disinfection and quarantine which have hereto- 

 fore been considered necessary in yellow-fever epi- 

 demics, and in the case of infected ships, have 

 already been discontinued in Havana, and will 

 probably soon be discarded elsewhere. Dr. Doty, 

 the health officer of the port of New York, has 

 recommended their discontinuance in that city. 



At the annual Conference of State and Provin- 

 cial Boards of Health of North America, held at 

 New Haven, Oct. 28 and 29, 1902, Major Gorgas 

 offered the following resolution: 



" Resolved, That in view of the establishment 

 of the fact that yellow fever is transmitted only 

 by the mosquito, this conference is of the opin- 

 ion that there is no longer necessity for the dis- 

 infection of clothing in yellow-fever cases, bed- 

 ding fabrics, or effects of any kind, but simply 

 to take measures looking to the control of the 

 sick and the extermination of infected mosqui- 

 toes. In cases in which non-immunes have been 

 exposed to infection, they should be observed dur- 

 ing the period of incubation." 



This resolution was the report of the Committee 

 on Yellow-Fever Resolutions. It was spread upon 

 the proceedings, but the conference refused to 

 commit itself to the " sole mosquito theory." 



At the meeting of the American Public Health 

 Association in New Orleans early in December 

 a long discussion of yellow fever and mosquitoes 

 occurred; but although a majority of the dele- 

 gates believed in the theory which holds the mos- 

 quito to be the sole causative agent, a small 

 minority, who remained unconvinced, prevented 

 a resolution favoring open quarantine. 



The report of the Surgeon-General of the Uni- 

 ted States Army for the fiscal year ending June 

 30, 1902, states that there were recorded during 

 the year 35,180 cases of malarial disease, with a 

 death-rate of only 0.59 per cent. Important re- 

 sults regarding cases of so-called latent and 

 masked infection were obtained at the Presidio 

 general hospital in San Francisco. It is well 

 known that malarial infections may remain la- 

 tent for long periods. Among the returned sol- 

 diers from the Philippines, 219 of the 1,082 cases 

 (20 per cent.) which showed malarial parasites 

 in the blood were found to be of the latent type. 

 The report insists on the importance of blood 

 examinations in all tropical diseases, and states 

 that a malarial infection complicating any other 

 disease seriously compromises the patient's 

 chances of recovery. Cases have been observed 

 where the discovery of the malarial parasite has 

 undoubtedly saved the patient's life. 



Of interest in connection with the mosquito 

 diseases is a recent monograph on The Culicidee 

 of the World, in three volumes, by F. W. Theo- 



