500 
THOMPSON YATES LABORATORIES REPORT 
With great boldness, and fortunately without fatal accidents, Major Reed and 
his comrades carried out a number of experimental inoculations of yellow fever in 
human subjects. These are reported in three communications, which, for reference, 
may be styled I, II, and III respectively. 1 The first two apparently successful inocula- 
tions were'most unhappily somewhat vitiated by the accidental infection of Dr. Lazear, 
which, sad to repeat, was followed by fatal result, whilst engaged in more or less 
similar work to case 10 (I); this case, therefore, did not seem necessarily to be in 
consequence of the effect of the artificial inoculation. 
In the succeeding cases efforts were made to keep the subjects away from the 
possibility of accidental infection. This may be summed up under three headings — 
(i) the presence of controls, (2) quarantining the subjects, and (3) locating the subjects 
outside the endemic area. The validity of the cases then depends upon the absence 
of spontaneous or sporadic cases amongst the controls, upon the efficiency of the 
supervision used upon those in quarantine, and the certainty that accidental infection 
might not occur from unguarded sources. It is perhaps to be regretted that more 
detailed account of the attempts to exclude accidental contamination were not given, 
especially the supervision at night. Again, the question of the isolation of the 
experimental camp leaves something to be desired, for instance, it is stated (II) that 
the camp 'Lazear' was 'about one mile from the town of Quemados, Cuba.' 
Quemados, it may be noted, is a straggling town, one street of which extends 
almost to the 'Quemados entrance' to 'Columbia camp,' in the grounds of which 
the experimental station, camp 'Lazear,' was situate; the railway line leading on to 
Marianao intervening between the two. Since the houses in this street were severely 
infected just previously to the commencement of the experiments, and that one 
next but one to the railway had been destroyed in consequence, for the judgment of 
the completeness of the isolation the distance from this region would have been 
useful. Again, the prevalence of yellow fever in the surroundings, and the possibility 
of introduction therefrom should be considered, as some distance further along the 
line a fatal case is reported from Marianao (v. Major Gorgas, November, 1900, Rep.). 
During the latter months of 1900 the fever seems to have been more prevalent in 
Habana than in the two previous years, e.g., October, 1897, forty-two deaths ; 1898, 
twenty-six deaths; 1899, twenty-five deaths; in 1900, seventy-four deaths. In 
November, 1900, fifty-eight deaths occurred, including cases from surrounding 
townships. 
1. I, Philadelphia Medical Journal, October 27, 1900 ; II, Journal of the American Medical Association, February 16, 
1901 ; and III, American Medicine, July 6, 1901. 
