in June 1900, he hud the opportunit}' to observe an epidemic of yellow fever at the little town of Pinar del Rio, ami what he then saAV convinced him that tlie prevail- ing belief in the transmission of the dis- ease by means of fomites conveyed in clothinfj;, bedding, etc., was erroneous, lie determined, therefore, that the search for the specific cause of the disease, upon which up to that time all effort had been concentrated, had better be abandoned, and ever}' energy bent upon disco\ering the means by which it was transmitted. The line of investigation which, in his opinion, ofTered most prospect of success was the theory suggested by Dr. (,'arlos Finlay in 1882 that the disease was con- vej'ed from one person to another by a certain species of mosquito, the stegoniyin fasciata. Some preliminary exj^eriments showed that there was reason to believe in the truth of this supposition, and an ex- perimental sanitary station, called Camp Lazear, was established by Reed near Quemados, in order that further experi ments might be carried on under condi- tions of absolute security.
The first experiment at Camp Lazear was made upon a young private from the United States Army, John R. Kissinger from Ohio, who volunteered to be bitten by mosquitoes which had bitten a yellow- fever patient. Kissinger was kept in strict quarantine for two weeks and was then bitten by some mosquitoes which had been purposely infected fifteen to twenty days previously. At the end of three and a half days the disease devel- oped and he had it in a typical form. This experiment was confirmed by others of the same nature, proving conclusively that yellow fever is transmitted by the stegomyia fasciata.
It was next necessary to prove that the disease is not conveyed by fomites and for this purpose a building was especial!}- constructed by Maj. Reed from which all ventilation was excluded, the tempera- ture being extremely hot and the atmos- phere damp. In this building Dr. E. G. Cooke and two private soldiers. Folk and Jernigan, volunteered to sleep for
twenty nights surrounded by articles of clothing and bedding used by yellow fever patients and soiled by discharges. Not a single case of the disease developetl and the same experiment repeated on several subsequent occasions was fol- lowed by the same negative result.
These experiments were succeeded by others for the purpose of investigating various secondary points connected with the moscpiito theory of the tlisease, the facts established altogether being these: The mosquito, stegomyia fasciata, serves as the intermediate host for the parasite of the yellow fever.
Yellow fever is not conveyed by fomites, hence disinfection of articles supposed to be contaminated by the dis- ease is unnecessary.
The infection of a building with yellow fever is due to the presence of mosquitoes which have bitten some one with the disease.
Yellow fever can be produced experi- mentally by the subcutaneous injection of blood taken from the general circula- tion during the first, second and third days of the disease.
Intervals of at least twelve days must elapse after the mosquito has bitten a yellow fever patient before it is capable of transmitting the disease. The bite of the mosquito at an earlier date after contamination does not appear to convey any immunity against a sub- sequent attack.
The mosquito is capable of infection for at least fifty-seven days after con- tamination and possibly longer.
On the conclusion of these experiments, in February, 1901, Maj. Reed returned to his work in Washington, where he was professor of bacteriology and clinical microscopy in the Army Medical School, and of pathology and bacteriology in the Columbian University. His natural aptitude for teaching appears to have been great and as the subjects which he taught were then comparatively un- known, he was compelled to develop his own methods of instruction, a fact which imparted an originality to his lectures