53° 
THOMPSON YATES LABORATORIES REPORT 
F. Yellow Fever on Ships 
S.S. ' D.' Arrived at Para on November 25. Perfectly good health on voyage ; 
none of the crew allowed on shore ; the oniy things brought on board from shore 
were beef, fish, vegetables, and ice ; all of this carried out from the city (about two 
miles away) by the tender ; otherwise only discharge of the cargo has taken place, 
namely, into nine lighters. No water was taken on board. 
On December 2, B. (third officer) taken ill ; seen on eighth day ; certain yellow 
fever ; transferred to hospital. 
On December 7, boy (mess steward) taken suddenly ill, with temperature of 
104-5°. 
On December 8, ordinary seaman taken ill with fever. 
On December 10, second officer was not well, but no rise of temperature. 
Owing to only receiving information concerning this just before the vessel 
sailed, these last three cases could not be examined ; it was stated that none had any 
jaundice, nor did they have definite sweating attacks. 
The vessel then proceeded to Manaos to discharge and receive cargo. It was 
stated that on the voyage up river one ordinary seaman was taken ill, but no details 
were forthcoming. 
On leaving Manaos, D.I., a fireman, was taken ill on December 19. He was 
transferred to hospital on fourth day, where he showed symptoms of severe yellow 
fever (black vomit, bleeding from gums, delirium, icterus, prostration, and large 
quantities of albumin in the urine). 
S.S. ' H.' Two men (third steward and a fireman) were taken ill on leaving 
Manaos, where the vessel had been for twelve days, on February 24, 1 901. The 
former had a well marked moderately severe attack of yellow fever ; the other gave a 
history of bilious vomiting, but on admission to hospital, on March 1, no definite 
symptoms of fever could be detected. 
In the case of the steamer ' D,' it is certain that at least one case of yellow fever 
developed on board in a person who had not been within about two miles of the 
city (Para). The only possible modes of convection of the infection would be (1) the 
food brought off, (2) the contact with the labourers who came to discharge the cargo, 
(3) infective material brought off in the tender or lighters, other than the items 
mentioned in (1) and (2). 
The first two points may be discarded, for it is unlikely that so few out of a 
population of thirty should have been taken ill if infected food had been the cause ; 
in regard to the second heading, we know that far more intimate contact (e.g., handling 
yellow fever patients or performing autopsies) than would occur under the conditions 
is not able to confer the fever. 
