276 The Control of Mosquitoes 



cember six cases developed. There were no deaths. 

 No cases appeared among Canal employees in 

 1904. In January, 1905, eight more cases were 

 reported, two resulting fatally. Three cases of 

 yellow fever developed on board the steamship. 

 Dora, en route to Havana from Colon. They 

 were Italians, members of an opera troupe, and 

 contracted yellow fever while sojourning in Colon. 

 Two of these cases terminated fatally. 



An outbreak of yellow fever occurred on the 

 U. S. Cruiser Boston, while she was at target prac- 

 tice at Chame Point, in Panama Bay. The Boston 

 was in Panama harbor during November, 1904. 

 Six cases developed on board the ship. The vessel 

 was thoroughly fumigated, and no further cases 

 followed. 



It was evident that strenuous measures were 

 needed to control the situation; but little help 

 could be counted on from the local native authori- 

 ties, and with the constantly increasing number 

 of non-immune arrivals, yellow fever cases would 

 increase in number, and assume the form of a 

 serious epidemic. The inspection force was 

 therefore increased to enable the inspection of all 

 houses once a week. All containers found with 

 mosquito larvK were washed out. Tanks and 

 larger vessels that could not be freed from larvae 



