III. REPORTS 
A. Preliminary Report 1 
Notwithstanding the acumen and the number of those who have attacked the 
question of the prevalence of yellow fever, much mystery and uncertainty still en- 
shroud the epidemiology of the disease. The etiology, also, is not yet determined 
with certainty; the claim of Sanarelli that his so-called '■Bacillus icteroides' is the true 
cause of yellow fever has not found favour with several workers who have made 
search in this direction. By the kind invitation of Dr. Sternberg, Surgeon-General 
of the U.S. Army, we had the opportunity of conferring with the commission (Drs. 
Reed, Carroll and Lazear) appointed by him to study the question in Cuba. We 
may here express our gratitude to these gentlemen for the most kind and courteous 
reception that they extended towards us, as well as to Major Gorgas (U.S. Army), 
the head of the bureau of inspection of infectious diseases in the city of Havana. We 
also had the pleasure and advantage of meeting Dr. Carter (of the U.S. Maine 
Hospital Service), Dr. Guiteras (now Professor in the Havana School of Tropical 
Diseases), Dr. Finlay, and Drs. Banco and Martinez (practitioners in the city). 
Amongst the many conflicting opinions and statements concerning the disease it 
appears certain that neither the handling of or contact with yellow fever patients nor 
the performance of necropsies is capable per se of conveying the disease to non- 
immunes. It also appears probable that general ship's cargoes and the fomites of 
patients are also not directly infective ; here, however, the evidence is not conclusive, 
and the present quarantine regulations require disinfection of all clothes and personal 
effects before they may be introduced into the United States. 
It seems to be fairly definitely established that a yellow-fever patient may become 
a danger by ' infecting the house ' in which he is placed. Given that a house is 
' infected,' a visit by a non-immune person entails considerable risk of contracting the 
malady. It is alleged by some that visits made at night are more dangerous than 
those made during the daytime ; but here the evidence is not very clear, and is more 
of the nature of an opinion. The nature of the essential factor present in an 'infected 
house ' is as yet mysterious. One house after another in a street may become 
- infected ' without any apparent intercommunication of the inmates ;' the infection 
may skip over one or more houses and reappear at some distance. There are those 
who are bold enough to predict in a village that such and such a house will yield one 
or more cases of the fever on or about a certain day ; and, naturally, they claim to 
be true prophets. 
i. Reprinted from British Medical Journal. 
