320 



FEVER, YELLOW. 



The table on page 321 shows the rise and fall 

 of the epidemics of 1853, 1867, and 1878. The 

 thirtieth day of the fever in 1853 was the 31st 

 of July ; in 1867, the thirtieth day was the 31st 

 of August; while in 1878 the thirtieth day was 

 the 16th of August. It will be seen that the 

 epidemic of 1853 culminated on the fifty-third 

 day of its prevalence, which was the 22d day 

 of August ; on that day there were 254 deaths 

 of yellow fever. In 1867 the epidemic culmi- 

 nated on the fifty-fifth day of its prevalence, 

 which was the 24th of October ; on that day 

 there were 82 deaths. The epidemic of 1878 

 culminated on the fifty-seventh day of its prev- 

 alence, which was the llth of September; on 

 that day there were 90 deaths. 



One of the most important discoveries du- 

 ring this season is due to the investigations of 

 Professor Joseph Jones, with the microscope, 

 on the blood of yellow-fever patients. It dif- 

 fers essentially from that of malarial-fever 

 patients. In yellow fever he found that the 

 blood corpuscles rapidly assume a cuneated 

 form, with minute translations upon the sur- 

 faces. In some cases it contains small particles 

 having a vibratory motion. 



I have also observed bacteria and a singular del- 

 icate fungus in the blood of yellow-fever patients. 

 Blood has been allowed to stand, and the develop- 

 ment of the fungus has been watched. If fresh 

 blood from yellow-fever patients be injected into an 

 animal, it will produce fever, but no animal has as 

 yet died from it. If, however, the blood be allowed 

 to stand for a short time, say several hours, it will 

 undergo chemical change or putrefaction, and will 

 then prove rapidly fatal to animals, even when in- 

 iected in minute quantities under the skin. Fresh 

 black vomit, introduced subcutaneously, acts as a 

 local irritant, and also produces fever. If black 

 vomit be introduced from the stomach of a dead 

 man, or if that from a living person be allowed to 

 undergo putrefactive change, it destroys in a few 

 hours the life of an animal to which it may be ad- 

 ministered under the skin. The black vomit in 

 many cases, a short time after ejection, becomes 

 filled with low forms of vegetable and animal life, 

 nuch a* the spores or thalli of torulse,the organized 

 bodies in yeast, and bacteria. I have noticed as 

 characteristic of the secretions and excretions in 

 yellow fever an exceedingly delicate fungus, which 

 w evidently a species of the plant which, produces 

 mentation in beer and yeast. We may take two 

 f the agency of these organisms in the spread 

 of yellow fever, and also two views as to the nature 

 of the disease. 



. As to the nature of the disease: Yellow fever 



may be regarded as a disease depending solely upon 



igea of heat, moisture, and other climatic con- 



ms, acting upon the human constitution in a 



am state : or to the absence of ozone or elec- 



icity from the atmosphere. But if this theory were 

 true, the disease would appear in all quarters of the 

 citv simultaneously, and not ramify, as it does, from 

 a focus and along lines of travel. A modification of 

 this theory might be this : that heat and moisture 



and surrounding climatic conditions, affecting the 

 constitution when in a certain state, cause tbe devel- 

 opment of a certain poison in the system thus acted 

 upon and in this peculiar state, which is capable, 

 after being developed, of propagating itself, such 

 propagation being due to two causes : first, the di- 

 rect emission of some poison from the person in- 

 fected, either from the breath or the secretions; 

 second, such poisons may be conveyed by minute 

 forms of plant or animal life, the plant or animal 

 finding a nest for its growth in secretions, as black 

 vomit and the excrement from the intestines, and 

 when excreted conveying the poison by being wafted 

 about by currents of air. 



2. Yellow fever may be due to special germs in- 

 digenous to a limited portion of the world. It may 

 be supposed that this germ exists independent of tbe 

 human organism, and may be transported in ships, 

 etc. ; that it thrives in its native locality, and while 

 it propagates outside of that locality it will not exist 

 for any length of time, frost killing it. With this 

 theory may be coupled the hypothesis that these 

 germs bave potency only when in contact with dis- 

 eased matter 1 have subjected the air of 



localities and rooms which appeared to be infected 

 with tbe yellow-fever poison to microscopical and 

 chemical examination, and I have discovered a vast 

 number* of minute organic living particles, which 

 might properly be termed sporules, having a diam- 

 eter varying from one ten-thousandth to one twenty- 

 thousandth of an inch; and also numerous living 

 animalcula, together with minute particles of fatty 

 bodies, scales from the human body, and fibers from 

 the bedding and clothing. I have observed similar 

 particles in the blood of yellow-fever patients, and 

 have found bacteria in the air and in the blood. The 

 blood was examined immediately after extraction, 

 under the microscope. I have endeavored to ascer- 

 tain whether these particles, or the matters obtained 

 from tbe air where yellow fever was prevailing, 

 would have any effect upon living animals. Nu- 

 merous experiments were made. These substances, 

 injected subcutaneously into animals, produced ir- 

 ritant effects, but not death, so far as the experiments 

 have been carried. 



Enough has been quoted to show the value 

 of this discovery, and at the same time to 

 prove the extreme diversity of opinion among 

 medical men on the most important points. 



At the Public Health Association, which 

 met in Eichmond, the Yellow Fever Commis- 

 sion reported : 



1. We have not in a single instance found :i case of 

 yellow fever which we could justifiably consider as of 

 de novo origin, or indigenous to the locality. 



2. In respect to most of the towns which we vis- 

 ited, and which were points of epidemic prevalence, 

 the testimony showing importation was direct ana 

 convincing in its character. 



3. The transmission of yellow fever between 

 points separated by any considerable distances ap- 

 peared to be wholly due to human intercourse. In 

 some instances the poison was carried in the cloth- 

 ing or about the persons of people going from in- 

 fected districts. In some instances it was conveyed 

 in such fomites as cotton-bagging, or goods of some 

 description, or bedding and blankets. 



* Incomplete. 



