YELLOW FEVER. 711 



II. YELLOW FEVEB. 



Yellow fever is peculiarly an American disease, 

 and it has reached other continents (e. g., Spain) 

 only in accidental ways and for brief periods. It 

 is possibly endemic in certain portions of West 

 Africa (Sierra Leone), to which it was probably 

 carried from the Antilles (Scheube). Scheube 

 regards the Antilles as the birthplace of yellow 

 fever. Knowledge of it extends only to the middle 

 of the seventeenth century, at which time it 

 surely existed in the West Indies. The dis- 

 ease has on several occasions been carried to 

 Spain by vessels returning from Cuban ports. 

 Until very recent times it was endemic in 

 Cuba, especially Havana, and in Vera Cruz 

 and other Spanish- American ports it has prevailed 

 extensively. From such points extension frequent- 

 ly takes place into adjacent tropical or subtropical 

 regions, or even into temperate localities during 

 the summer months. In the latter part of the 

 eighteenth century Philadelphia suffered very se- 

 verely. Baltimore was attacked similarly and Bos- 

 ton to a less degree. Other northern ports, e. g., 

 New York, have experienced attacks of limited 

 duration, the disease, presumably, being intro- 

 duced by means of infected ships. 



In addition to our southern coasts and that of 

 Mexico, the Atlantic coast of South America has 

 been infected as far south as Buenos Ayres, and 

 likewise the western coast of Mexico and Peru. In 

 the eighteenth century the coast of Spain and 

 Portugal suffered severely, but since that time 

 only minor epidemics have occurred in these coun- 

 tries. Epidemics frequently have appeared on 

 ships after they had left infected ports. 



